Patent Publication Number: US-2023158607-A1

Title: Processing system

Description:
TECHNICAL FIELD 
     The present invention relates to a technical field of a processing system that is configured to process an object, for example. 
     BACKGROUND ART 
     A Patent Literature 1 discloses one example of a processing system that is configured to process an object. Specifically, the Patent Literature  1  discloses a processing system that is configured to perform an additive processing on a workpiece by supplying a material powder to the workpiece that is one example of the object and by irradiating it with a laser light. One of a technical problem of this processing system is to properly process the object that is a processing target. 
     CITATION LIST 
     Patent Literature 
     Patent Literature 1: US2019/270246A1 
     SUMMARY OF INVENTION 
     A first aspect provides a processing system that is configured to process an object by using an energy beam, wherein the processing system includes: an irradiation optical system that includes a condensing optical system and that is configured to condense the energy beam entering a pupil plane of the condensing optical system to irradiate the object with it; and a detection apparatus that is configured to detect, through the condensing optical system, an object light including a light from the object, at least a part of a path of the object light in the condensing optical system is different from at least a part of a path of the energy beam in the condensing optical system. 
     A second aspect provides a processing system that is configured to process an object by using an energy beam, wherein the processing system includes: an irradiation optical system that is configured to irradiate the object with a plurality of energy beams as the energy beam; and a beam characteristic change apparatus that is configured to change a characteristic of at least one of the plurality of energy beams individually. 
     A third aspect provides a processing system that is configured to process an object by using an energy beam, wherein the processing system includes: an irradiation optical system that is configured to irradiate the object with a plurality of energy beams as the energy beam; and a beam characteristic change apparatus that is configured to change a characteristic of at least one of the plurality of energy beams, the characteristic of a first energy beam of the plurality of energy beams being different from the characteristic of a second energy beam of the plurality of energy beams. 
     A fourth aspect provides a processing system that is configured to process an object by using an energy beam, wherein the processing system includes: an irradiation optical system that is configured to irradiate the object with a plurality of energy beams as the energy beam; and a beam characteristic change apparatus that is configured to change a characteristic of at least one of the plurality of energy beams, the beam characteristic change apparatus being configured to set the characteristic of a first energy beam of the plurality of energy beams to be different from the characteristic of a second energy beam of the plurality of energy beams. 
     A fifth aspect provides a processing system that is configured to process an object by using an energy beam, wherein the processing system includes: an irradiation optical system that is configured to irradiate the object with a plurality of energy beams as the energy beam; 
     and a beam characteristic change apparatus that is configured to set a characteristic of a first energy beam of the plurality of energy beams to be different from a characteristic of a second energy beam of the plurality of energy beams. 
     A sixth aspect provides a processing system that is configured to process an object by using an energy beam, wherein the processing system includes: an irradiation optical system that is configured to irradiate the object with a plurality of energy beams as the energy beam; and a distance change apparatus that is configured to a distance between a plane on which the plurality of energy beams overlap with each other and a surface of the object to thereby change a distribution of the energy beam on the surface of the object. 
     An operation and another advantage of the present invention will be apparent from an example embodiment described below. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG.  1    is a cross-sectional view that illustrates a configuration of a processing system in a first example embodiment. 
         FIG.  2    is a system configuration diagram that illustrates a system configuration of the processing system in the first example embodiment. 
         FIG.  3    is a cross-sectional view that illustrates a configuration of a processing head (namely, an irradiation optical system and a material nozzle). 
         FIG.  4    is a cross-sectional view that illustrates a configuration of the processing head (namely, the irradiation optical system and the material nozzle). 
         FIG.  5    is a cross-sectional view that illustrates optical paths of processing lights in a virtual optical plane in a condensing optical system that intersects with an optical axis of the condensing optical system. 
         FIG.  6    is a cross-sectional view that illustrates another example of the optical paths of the processing lights with which the workpiece is irradiated through the condensing optical system. 
         FIG.  7    is a cross-sectional view that illustrates another example of areas through which the processing lights EL# 1  to EL# 4  pass in an optical plane OP. 
         FIG.  8 A  is a planar view that illustrates the processing lights with which the workpiece is irradiated and  FIG.  8 B  is a cross-sectional view that illustrates the processing lights with which the workpiece is irradiated. 
         FIG.  9 A  is a planar view that illustrates the processing lights with which the workpiece is irradiated and  FIG.  9 B  is a cross-sectional view that illustrates the processing lights with which the workpiece is irradiated. 
         FIG.  10    Each of  FIG.  10 A  to  FIG.  10 E  is a cross-sectional view that illustrates an aspect when a certain area on the workpiece is irradiated with the processing light and build materials are supplied thereto. 
         FIG.  11    Each of  FIG.  11 A  to  FIG.  11 C  is a cross-sectional view that illustrates a process for forming a three-dimensional structural object. 
         FIG.  12    is a planar view that illustrates target irradiation areas (namely, irradiation positions of the processing lights) moving toward a +Y side along a Y axis direction on a build surface. 
         FIG.  13    Each of  FIG.  13 A  and  FIG.  13 B  is a graph that illustrates intensities of the processing light with which a position at a relatively rear side along a moving direction is irradiated and the processing light with which a position at a relatively front side along the moving direction is irradiated. 
         FIG.  14    is a graph that illustrates the intensities of the processing light with which the position at the rear side relative to the moving direction is irradiated and the processing light with which the position at the front side relative to the moving direction is irradiated. 
         FIG.  15    Each of  FIG.  15 A  and  FIG.  15 B  is a cross-sectional view that illustrates an aspect in which the processing lights are emitted toward the target irradiation areas set on the build surface. 
         FIG.  16    is a cross-sectional view that illustrates the optical paths of the processing lights in the virtual plane in the condensing optical system that intersects with the optical axis of the condensing optical system. 
         FIG.  17    is a planar view that illustrates one example of a desired-shaped beam spot formed by the plurality of processing lights on the build surface. 
         FIG.  18    is a cross-sectional view that illustrates a configuration of a processing system in a second example embodiment. 
         FIG.  19    is a system configuration diagram that illustrates a system configuration of the processing system in the second example embodiment. 
         FIG.  20    is a cross-sectional view that illustrates optical paths of a measurement light and an object light in the irradiation optical system (especially, in the condensing optical system) in the second example embodiment. 
         FIG.  21    is a XX-XX′ cross-sectional view of  FIG.  20   . 
         FIG.  22    is a system configuration diagram that illustrates a system configuration of the processing system in a third example embodiment. 
         FIG.  23    is a cross-sectional view that illustrates a configuration of an irradiation optical system in the third example embodiment. 
         FIG.  24    Each of  FIG.  24 A  to  FIG.  24 C  is a cross-sectional view that illustrates an example of the optical path of the measurement light with which the build surface is irradiated. 
         FIG.  25    is a system configuration diagram that illustrates a system configuration of a processing system in a fourth example embodiment. 
         FIG.  26    is a cross-sectional view that illustrates optical paths of the measurement light and a returned light in the irradiation optical system (especially, the condensing optical system) in the fourth example embodiment. 
         FIG.  27    is a XXVI-XXVI′ cross-sectional view of  FIG.  26   . 
         FIG.  28    is a system configuration diagram that illustrates a system configuration of a processing system in a fifth example embodiment. 
         FIG.  29    is a planar view that conceptionally illustrates operations of a collection apparatus and a gas supply apparatus in the fifth example embodiment. 
         FIG.  30    is a system configuration diagram that illustrates a system configuration of a processing system in a sixth example embodiment. 
         FIG.  31    is a cross-sectional view that illustrates a configuration of a surrounding member in the sixth example embodiment. 
         FIG.  32    is a system configuration diagram that illustrates a system configuration of a processing system in a seventh example embodiment. 
         FIG.  33    is a cross-sectional view that illustrates a configuration of the processing system in the seventh example embodiment. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     Next, with reference to drawings, a processing system SYS that is one example embodiment of a processing system in the present invention will be described. In the below described description, a positional relationship of various components that constitute the processing system SYS will be described by using an XYZ rectangular coordinate system that is defined by a X axis, a Y axis and a Z axis that are perpendicular to one another. Note that each of an X axis direction and a Y axis direction is assumed to be a horizontal direction (namely, a predetermined direction in a horizontal plane) and a Z axis direction is assumed to be a vertical direction (namely, a direction that is perpendicular to the horizontal plane, and substantially an up-down direction) in the below described description, for convenience of the description. Moreover, rotational directions (in other words, inclination directions) around the X axis, the Y axis and the Z axis are referred to as a OX direction, a OY direction and a OZ direction, respectively. Here, the Z axis direction may be a gravity direction. Moreover, an XY plane may be a horizontal direction. 
     (1) Processing System SYS in First Example Embodiment 
     Firstly, the processing system SYS in a first example embodiment (hereinafter, the processing system SYS in the first example embodiment is referred to as a “processing system SYSa”) will be described. The processing system SYSa in the first example embodiment is a processing system that is configured to form a three-dimensional structural object ST by performing an additive processing. The processing system SYSa is configured to form the three-dimensional structural object ST by performing the additive processing based on a LMD (Laser Metal Deposition), for example. Note that the Laser Metal Deposition may be referred to as a Direct Metal Deposition, a Direct Energy Deposition, a Laser Cladding, a Laser Engineered Net Shaping, a Direct Light Fabrication, a Laser Consolidation, a Shape Deposition Manufacturing, a Wire Feed Laser Deposition, a Gas Through Wire, a Laser Powder Fusion, a Laser Metal Forming, a Selective Laser Powder Re-melting, a Laser Direct Casting, a Laser Powder Deposition, a Laser Additive Manufacturing or a Laser Rapid Forming. However, the processing system SYSa may form the three-dimensional structural object ST by performing the additive processing based on another additive processing method. 
     Next, a configuration and an operation of the processing system SYSa performing the additive processing will be described in order. 
     (1-1) Configuration of Processing System SYSa 
     Firstly, with reference to  FIG.  1    and  FIG.  2   , a configuration of the processing system SYSa in the first example embodiment will be described.  FIG.  1    is a cross-sectional view that conceptionally illustrates one example of the configuration of the processing system SYSa in the first example embodiment.  FIG.  2    is a system configuration diagram that illustrates a system configuration of the processing system SYSa in the first example embodiment. 
     The processing system SYSa is configured to form the three-dimensional structural object ST (namely, a three-dimensional object having a size in each of three-dimensional directions, a solid object, in other words, an object having a size in the X axis direction, the Y axis direction and the Z axis direction). The processing system SYSa is configured to form the three-dimensional structural object ST on the workpiece W that is a base (namely, a base member) for forming the three-dimensional structural object ST. The processing system SYSa is configured to form the three-dimensional structural object ST by performing the additive processing on the workpiece W. When the workpiece W is a below described stage  41 , the processing system SYSa is configured to form the three-dimensional structural object ST on the stage  41 . When the workpiece W is a placed object that is an object placed on the stage  41 , the processing system SYSa is configured to form the three-dimensional structural object ST on the placed object. In this case, the processing system SYSa may form the three-dimensional structural object ST that is integrated with the placed object. An operation for forming the three-dimensional structural object ST that is integrated with the placed object is equivalent to an operation for adding a new structural object to the placed object. Note that the existing structural object may be an item that needs to be repaired having a missing part, for example. The processing system SYSa may form the three-dimensional structural object on the item that needs to be repaired to fill in the missing part of the item that needs to be repaired. Alternatively, the processing system SYSa may form the three-dimensional structural object ST that is separable from the placed object. The placed object placed on the stage  41  may be another three-dimensional structural object ST (namely, an existing structural object) formed by the processing system SYSa. In the below described description, an example in which the workpiece W is the placed object placed on the stage  41  will be described. Incidentally, in the below described description, the workpiece W means both of the workpiece W on which the three-dimensional structural object ST is not formed and the workpiece W on which at least a part of the three-dimensional structural object ST has been formed (namely, the workpiece W including at least a part of the three-dimensional structural object ST that has been formed). 
     As described above, the processing system SYSa is configured to form the three-dimensional structural object ST by the Laser Metal Deposition. Namely, it can be said that the processing system SYSa is a 3D printer that forms an object by using an Additive layer manufacturing technique. Note that the Additive layer manufacturing technique may be referred to as a Rapid Prototyping, a Rapid Manufacturing or an Additive Manufacturing. 
     The processing system SYSa forms a build object by processing a build material M with a processing light EL. The build material M is a material that is molten by an irradiation with the processing light EL having a predetermined intensity or more intensity. At least one of a metal material and a resin material is usable as the build material M, for example. However, another material that is different from the metal material and the resin material may be used as the build material M. The build materials M are powder-like or grain-like materials. Namely, the build materials M are powdery materials. However, the build materials M may not be the powdery materials. For example, a wired-like build material or a gas-like build material may be used, as the build material M, for example. 
     In order to form the three-dimensional structural object ST, the processing system SYSa includes a material supply source  1 , a plurality of processing light sources  2 , a processing apparatus  3 , a stage apparatus  4 , a gas supply source  5  and a control apparatus  6 , as illustrated in  FIG.  1    and  FIG.  2   . The processing apparatus  3 , the stage apparatus  4  may be housed in a chamber space  73 IN in the housing  7 . 
     The material supply source  1  is configured to supply the build materials M to the processing apparatus  3 . The material supply source  1  supplies, to the processing apparatus  3 , the build materials M the amount of which is necessary for forming the three-dimensional structural object ST per unit time by supplying the build materials M the amount of which is based on the necessary amount. 
     Each of the plurality of processing light sources  2  is configured to emit at least one of an infrared light, a visible light and a ultraviolet light as the processing light EL, for example. However, another type of light may be used as the processing light EL. The processing light EL may include a pulsed light (namely, a pulsed beam). The processing light EL may be a laser light. In this case, each of the plurality of the processing light sources  2  may include a laser light source (for example, a semiconductor laser such as a laser diode (LD). The laser light source may include a fiber laser, a CO 2  laser, a YAG laser, an Excimer laser and the like. However, the processing light EL may not be the laser light. In this case, the processing light source  2  may include any light source (for example, at least one of a LED (Light Emitting Diode), a discharge lamp and the like). Note that the first example embodiment illustrates an example in which the processing system SYSa include four processing light sources  2  (specifically, a processing light source  2 # 1  emitting a processing light EL# 1 , a processing light source  2 # 2  emitting a processing light EL# 2 , a processing light source  2 # 3  emitting a processing light EL# 3  and a processing light source  2 # 4  emitting a processing light EL# 4 ). However, the number of the processing light source  2  may be equal to or larger than  3  or may be equal to or larger than  5 . 
     The processing apparatus  3  forms the three-dimensional structural object ST by processing the build materials M supplied from the material supply source  1  with the processing lights EL# 1  to EL# 4  transmitted from the processing light sources  2 # 1  to  2 # 4 , respectively. In order to form the three-dimensional structural object ST, the processing apparatus  3  include a processing head  31  and a head driving system  32 . However, the processing apparatus  3  may not include the head driving system  32 . Furthermore, the processing head  31  includes an irradiation optical system  311  and a material nozzle  312  (namely, a material supply apparatus that supplies the build materials M). The processing head  31  and the head driving system  32  are hosed in the chamber space  731 N. However, at least a part of the processing head  31  and/or the head driving system  312  may be disposed in an external space  74 OUT that is a space outside the housing  7 . Note that the external space  74 OUT may be a space into which an operator of the processing system SYSa is allowed to enter. 
     Here, with reference to  FIG.  3    and  FIG.  4    in addition to  FIG.  1    and  FIG.  2   , the processing head  31  (namely, the irradiation optical system  311  and the material nozzle  312 ) will be described.  FIG.  3    and  FIG.  4    are cross-sectional views that illustrate a configuration of the processing head  31  (namely, the irradiation optical system  311  and the material nozzle  312 ). 
     As illustrated in  FIG.  1    to  FIG.  4   , the irradiation optical system  311  is an optical system which the processing lights EL# 1  to EL# 4 , which are transmitted from the processing light sources  2 # 1  to  2 # 4 , respectively, enter. The irradiation optical system  311  is an optical system for emitting the processing lights EL# 1  to EL# 4  that enter the irradiation optical system  311 . Specifically, the irradiation optical system  311  is optically connected to the processing light sources  2 # 1  to  2 # 4  through a plurality of light transmitting members  21  including at least one of an optical fiber, a light pipe and so on. More specifically, the irradiation optical system  311  is optically connected to the processing light source  2 # 1  through the light transmitting member  21 # 1 , is optically connected to the processing light source  2 # 2  through the light transmitting member  21 # 2 , is optically connected to the processing light source  2 # 4  through the light transmitting member  21 # 3 , and is optically connected to the processing light source  2 # 4  through the light transmitting member  21 # 4 . The irradiation optical system  311  emits the processing lights EL# 1  to EL# 4  transmitted from the processing light sources  2 # 1  to  2 # 4  through the light transmitting members  21 # 1  to  21 # 4 . The irradiation optical system  311  emits the processing lights EL# 1  to EL# 4  in a downward direction (namely, toward a −Z side) from the irradiation optical system  311 . The stage  41  is disposed below the irradiation optical system  311 . When the workpiece W is placed on the stage  41 , the irradiation optical system  311  emits the processing lights EL# 1  to EL# 4  toward the workpiece W. 
     The irradiation optical system  311  may condenses, on the workpiece W, the processing lights EL# 1  to EL# 4  emitted toward the workpiece W. In order to condenses the processing lights EL# 1  to EL# 4 , the irradiation optical system  311  may include a condensing optical system  3111 . The condensing optical system  3111  is an optical system that includes a plurality of optical members  3112  (for example, lenses), however, may be an optical system that includes a single optical member  3112 . The processing lights EL# 1  to EL# 4  are emitted from a terminal optical member  3114  that is located at the position closest to the workpiece W (in an example illustrated in  FIG.  3    and  FIG.  4   , located at the most −Z side) along optical paths of the processing lights EL# 1  to EL# 4  among the plurality of optical members  3112  (especially, the plurality of optical members  3112  having a power) of the condensing optical system  3111 . Note that the terminal optical member  3114  may be referred to as a final optical member. 
     The processing lights EL# 1  to EL# 4  emitted from the condensing optical system  3111  are condensed on a condensed plane FP that are virtual optical plane intersecting with an optical axis AX of the condensing optical system  3111  (namely, an optical axis of the irradiation optical system  311 ). Thus, the condensing optical system  3111  may be regarded to be an optical system for condensing the processing lights EL# 1  to EL# 4  entering a pupil plane (an incident pupil plane) of the condensing optical system  3111  on the condensed plane FP of the condensing optical system  3111 . Here, a state where “the processing lights EL# 1  to EL# 4  are condensed on the condensed plane FP” in the first example embodiment may mean a state where “the processing lights EL# 1  to EL# 4  are overlapped with each other on the condensed plane FP”. Namely, the state where “the processing lights EL# 1  to EL# 4  are condensed on the condensed plane FP” in the first example embodiment may mean a state where “a same position on the condensed plane FP is irradiated with the processing lights EL# 1  to EL# 4 ”. The condensed plane FP is typically set at a rear focal point position of the condensing optical system  3111 . Note that  FIG.  3    and  FIG.  4    illustrate an example in which the condensed plane FP is set on a surface WS of the workpiece W. Incidentally, the condensed plane FP is a plane that intersects with the Z axis (for example, a plane along the XY plane), because the optical axis AX is an axis along the Z axis. Note that the incident pupil plane of the condensing optical system  3111  is located outside (at an incident side of) the condensing optical system  3111  in this example, however, the incident pupil plane of the condensing optical system  311 may be located in the condensing optical system  3111 . 
     The optical paths of the processing lights EL# 1  to EL# 4  (namely, paths along which the processing lights EL# 1  to EL# 4  propagate) may be optically separated from each other in the condensing optical system  3111 . Namely, the optical paths of the processing lights EL# 1  to EL# 4  may be different from each other in the condensing optical system  3111 . Namely, the optical paths of the processing lights EL# 1  to EL# 4  may not be overlapped with each other in the condensing optical system  3111 . 
     In order to optically separate the optical paths of the processing lights EL# 1  to EL# 4 , for example, as illustrated in  FIG.  5    that is a cross-sectional view illustrating the optical paths of the processing lights EL# 1  to EL# 4  in a virtual optical plane OP (typically, a plane along the XY plane, and the incident pupil plane of the condensing optical system  3111 , for example) in the condensing optical system  3111  that intersects with the optical axis AX of the condensing optical system  3111 , the processing lights EL# 1  to EL# 4  may pass through different areas, respectively, that are away from the optical axis AX toward different directions in the optical plane OP. In this case, a distance between the optical axis AX and the optical path of the processing light EL# 1 , a distance between the optical axis AX and the optical path of the processing light EL# 2 , a distance between the optical axis AX and the optical path of the processing light EL# 3  and a distance between the optical axis AX and the optical path of the processing light EL# 4  may be equal to one another in the optical plane OP. Alternatively, the distances between the optical axis AX and the optical paths of at least two of the processing lights EL# 1  to EL# 4  may be different from each other. In an example illustrated in  FIG.  3    to  FIG.  5   , the distances between the optical axis AX and the optical paths of the processing lights EL# 1  to EL# 4  are equal to one another in the optical plane OP. In this case, the processing lights EL# 1  to EL# 4  may pass through areas that are rotationally symmetric about the optical axis AX (areas that are n-fold rotationally symmetric (note that n is an integer that is equal to or larger than  2 ) about the optical axis AX in the optical plane OP). For example, as illustrated in  FIG.  5   , the processing lights EL# 1  to EL# 4  may pass through four areas whose rotational angles along the clockwise direction around an origin are 270 degree, 90 degree, 0 degree and 180 degree (alternatively, θ+270 degree (note that θ is a desired angle), θ+90 degree, θ degree and θ+180 degree) (areas that are 4-fold rotationally symmetric about the optical axis AX in the optical plane OP) in a coordinate plane along the XY plane the origin of which is the optical axis AX. 
     When the processing lights EL# 1  to EL# 4  pass through the different areas, respectively, that are away from the optical axis AX toward the different directions in the optical plane OP, the condensing optical system  3111  may emit the processing lights EL# 1  to EL# 4  toward the workpiece W from different directions. Specifically, as illustrated in  FIG.  3    to  FIG.  5   , the condensing optical system  3111  may emit the processing lights EL# 1  to EL# 4  toward the workpiece W from positions that are different from one another along a rotational direction around the optical axis AX. 
     Alternatively, in order to optically separate the optical paths of the processing lights EL# 1  to EL# 4 , the processing lights EL# 1  to EL# 4  may pass through different areas, respectively, that are away from the optical axis AX toward same direction by different distances in the optical plane OP. For example, as illustrated in  FIG.  6    that is a cross-sectional view illustrating another example of the optical paths of the processing light EL# 1  to EL# 4  with which the workpiece W is irradiated through the condensing optical system  3111  and  FIG.  7    that is a cross-sectional view illustrating another example of the areas through which the processing lights EL# 1  to EL# 4  pass in the optical plane OP, the processing lights EL# 1  to EL# 4  may pass through different areas, respectively, that are away from the optical axis AX toward the +Y side by different distances. Namely, the processing lights EL# 1  to EL# 4  may pass through different areas, respectively, that are away from the optical axis AX toward same direction by different distances so that the distance between the optical axis AX and the optical path of the processing light EL# 1 , the distance between the optical axis AX and the optical path of the processing light EL# 2 , the distance between the optical axis AX and the optical path of the processing light EL# 3  and the distance between the optical axis AX and the optical path of the processing light EL# 4  are different from one another. 
     When the processing lights EL# 1  to EL# 4  pass through different areas, respectively, that are away from the optical axis AX toward same direction by different distances in the optical plane OP, the condensing optical system  3111  may emit the processing lights EL# 1  to EL# 4  toward the workpiece W so that angles between the optical axis AX and propagating directions of the processing lights EL# 1  to EL# 4  propagating from the condensing optical system  3111  to the workpiece W are different from one another. Specifically, as illustrated in  FIG.  6   , the condensing optical system  3111  may emit the processing lights EL# 1  to EL# 4  toward the workpiece W so that the angle between the optical axis AX and the propagating direction of the processing light EL# 1 , the angle between the optical axis AX and the propagating direction of the processing light EL# 2 , the angle between the optical axis AX and the propagating direction of the processing light EL# 3  and the angle between the optical axis AX and the propagating direction of the processing light EL# 4  are different from one another. 
     Note that positions of an emitting port of each of the light transmitting members  21 # 1  to  21 # 4  along the XY plane (a plane parallel to the optical plane OP) may be changeable in order to change the propagating directions of the plurality of processing lights EL# 1  to EL# 4  propagating from the condensing optical system  3111  to the workpiece W. Moreover, positions of the emitting port of each of the light transmitting members  21 # 1  to  21 # 4  along the Z axis may be changeable. Moreover, the propagating directions of the processing lights EL# 1  to EL# 4  emitted from the light transmitting members  21 # 1  to  21 # 4  (the propagating directions of the processing lights EL# 1  to EL# 4  between the condensing optical system and the light transmitting members  21 # 1  to  21 # 4 ) may be changeable. 
     An aperture  3113 , which penetrates each optical member  3112  in a direction along the optical axis AX, is formed at each optical member  3112  included in the condensing optical system  3111 . The aperture  3113  may be formed at a position at which the each optical member  3112  overlaps with the optical axis AX. Namely, the aperture  3113  may be formed on the optical axis AX. At least a part of the material nozzle  312  is disposed in the plurality of apertures  3113  that are formed at the plurality of optical members  3112 , respectively. At least a part of the material nozzle  312  is inserted into the plurality of apertures  3113 . In this case, the material nozzle  312  may be inserted into the apertures  3113  so that a supply outlet  314  at a head of the material nozzle  312  is located outside the apertures  3113 . Thus, the material nozzle  312  is disposed so that at least a part of the material nozzle  312  is surrounded by the plurality of optical members  3112 . When the apertures  3113  are formed on the optical axis AX, at least a part of the material nozzle  312  may be disposed along the optical axis AX in the apertures  3113 . In this case, the at least a part of the material nozzle  312  may be disposed on the optical axis AX. 
     When the aperture  3113  is formed at each optical member  3112 , the processing lights 
     EL# 1  to EL# 4  pass through a part of each optical member  3112  at which the aperture  3113  is not formed. When the aperture  3113  is formed on the optical axis AX as described above, the processing lights EL# 1  to EL# 4  pass through a part of each optical member  3112  that is away from the optical axis AX. In this case, the processing lights EL# 1  to EL# 4  may typically propagate from the condensing optical system  3111  to the workpiece W along directions that are inclined with respect to the optical axis AX. Namely, the condensing optical system  3111  may emit the processing lights EL# 1  to EL# 4  along the directions that are inclined with respect to the optical axis AX. 
     When the aperture  3113  is formed at each optical member  3112 , a purge gas supplied from the gas supply source  5  to the chamber space  73 IN may be supplied to a space at an emitting plane side of the terminal optical member  3114  (namely, a space at the workpiece W side) through the apertures  3113 . Specifically, the purge gas supplied from the gas supply source  5  to the chamber space  73 IN may be supplied a space between the plurality of optical members  3112  of the condensing optical system  3111 . The purge gas supplied to the space between the plurality of optical members  3112  of the condensing optical system  3111  may be supplied to a space at the emitting plane side of the terminal optical member  3114  through the apertures  3113  (especially, the aperture  3113  of the terminal optical member  3114 ). 
     The material nozzle  312  has the supply outlet  314 . The material nozzle  312  is configured to supply (specifically, inject, jet, blow out or spray) the build materials M from the supply outlet  314 . The material nozzle  312  is physically connected to the material supply source  1 , which is a supply source of the build materials M, through a supply pipe  11  and a mix apparatus  12 . The material nozzle  312  supplies the build materials M supplied from the material supply source  1  through the supply pipe  11  and the mix apparatus  12 . The material nozzle  312  may pressure-feed the build materials M supplied from the material supply source  1  through the supply pipe  11 . Namely, the build materials M from the material supply source  1  and a gas for feeding (namely, a pressure-feed gas, and an inert gas such as a Nitrogen or an Argon, for example) may be mixed by the mix apparatus  12  and then pressure-fed to the material nozzle  312  through the supply pipe  11 . As a result, the material nozzle  312  supplies the build materials M together with the gas for feeding. The purge gas supplied from the gas supply source  5  is used as the gas for feeding, for example. However, a gas supplied from a gas supply apparatus that is different from the gas supply source  5  may be used as the gas for feeding, for example. Note that the material nozzle  312  is illustrated to have a tube-like shape in  FIG.  3    and  FIG.  4   , however, a shape of the material nozzle  312  is not limited to this shape. The material nozzle  312  supplies the build materials M in a downward direction (namely, toward the −Z side) from the material nozzle  312 . In this case, since the material nozzle  312  is disposed in the apertures  3113  of the optical members  3112 , the material nozzle  312  may be regarded to supply the build materials M through the apertures  3113  of the optical members  3112  (especially, the aperture  3113  of the terminal optical member  3114 ). The material nozzle  312  may be regarded to supply the build materials M through a space located at an inner position than the optical paths of the processing lights EL# 1  to EL# 4  that are emitted through the part of the optical members  3112  at which the apertures  3113  are not formed. The stage  41  is disposed below the material nozzle  312 . When the workpiece W is placed on the stage  41 , the material nozzle  312  supplies the build materials M toward the workpiece W or a vicinity of the workpiece W. 
     The material nozzle  312  supplies the build materials M toward the workpiece W from a direction that intersects with the surface WS of the workpiece W. In the example illustrated in  FIG.  3    and  FIG.  4   , the material nozzle  312  supplies the build materials M toward the workpiece W from the Z axis direction that intersects with the surface WS of the workpiece W. Namely, the material nozzle  312  supplies the build materials M so that a supply path of the build materials M from the material nozzle  312  to the workpiece W is a path along the Z axis direction. In this case, a direction along which the material nozzle  312  supplies the build materials M toward the workpiece W (namely, a direction along the Z axis direction, an optical axis direction of the condensing optical system  3111 ) may be different from a direction along which the condensing optical system  3111  emits the processing lights EL# 1  to EL# 4  toward the workpiece W (namely, a direction that is inclined with respect to the Z axis or the optical axis AX). Namely, a supply direction (it may be referred to as a material supply direction) of the build materials M by the material nozzle  312  may be different from irradiation directions of the processing lights EL# 1  to EL# 4  by the condensing optical system  3111 . 
     In the present example embodiment, the material nozzle  312  is aligned to the irradiation optical system  311  so as to supply the build materials M to target irradiation areas EA that are irradiated with the processing lights EL# 1  to EL# 4  by the irradiation optical system  311  (namely, positions that are irradiated with the processing lights EL# 1  to EL# 4  by the irradiation optical system  311 ). Namely, the material nozzle  312  is aligned to the irradiation optical system  311  so that the target irradiation areas EA are coincident with (alternatively, at least partially overlaps with) a target supply area MA that is set on the workpiece W or near the workpiece W as an area to which the material nozzle  312  supplies the build materials M. moreover, as described later, a melt pool MP is formed on the workpiece W by the processing lights EL# 1  to EL# 4  emitted from the irradiation optical system  311 . The material nozzle  312  may be aligned to the irradiation optical system  311  so that the material nozzle  312  supplies the build materials M to the melt pool MP. However, the material nozzle  312  may not supply the build materials M to the melt pool MP. For example, the processing system SYSa may melt the build materials M by the processing lights EL# 1  to EL# 4  from the irradiation optical system  311  before the build materials M from the material nozzle  312  reaches the workpiece W and may allow the molten build materials M to adhere to the workpiece W. 
     As described above, the apertures  3113  in which the material nozzle  312  is disposed are used as a supply path of the purge gas supplied to the space at the emitting plane side of the terminal optical member  3114 . In this case, the purge gas supplied through the apertures  3113  forms a flow of a gas flowing to the supply outlet  314  at the head of the material nozzle  312 , for example. As a result, there is a high possibility that the build materials M from the supply outlet  314  are supplied along the supply path directed toward downward direction from the material nozzle  312 . Namely, there is a low possibility that the build materials M from the supply outlet  314  are scattered toward all directions from the material nozzle  312 . As a result, the material nozzle  312  is capable of properly supplying the build materials M. Namely, the processing system SYSa is capable of improving a directional characteristic of the supply direction of the build materials M. 
     Again in  FIG.  1    and  FIG.  2   , the head driving system  32  is configured to move the processing head  31 . The head driving system  32  moves the processing head  31  along at least one of the X axis, the Y axis, the Z axis, the OX direction, the OY direction and the OZ direction for example. When the head driving system  32  moves the processing head  31 , a relative position between the processing head  31  and each of the stage  41  and the workpiece W placed on the stage  41  changes. Namely, a relative position between each of the irradiation optical system  311  and the material nozzle  312  and each of the stage  41  and the workpiece W changes. Furthermore, when the relative position between each of the irradiation optical system  311  and the material nozzle  312  and each of the stage  41  and the workpiece W changes, the target irradiation area EA and the target supply area MA (furthermore, the melt pool MP) move relative to the workpiece W. Thus, the head driving system  32  may serve as a movement apparatus that is configured to move the target irradiation area EA and the target supply area MA (furthermore, the melt pool MP) relative to the workpiece W. 
     When the head driving system  32  moves the processing head  31  along the Z axis direction (namely, a direction along the optical axis AX of the condensing optical system  3111 ), a distance DS between the condensed plane FP of the condensing optical system  3111  on which the processing lights EL# 1  to EL# 4  are condensed and the surface WS of the workpiece W changes. Thus, the head driving system  32  may serve as a movement apparatus that is configured to change the distance DS between the condensed plane FP of the condensing optical system  3111  and the surface WS of the workpiece Win the Z axis direction. 
     The head driving system  32  may change the distance DS between the condensed plane FP and the surface WS of the workpiece W in the Z axis direction so that the condensed plane FP of the condensing optical system  3111  is located on the surface WS of the workpiece W (alternatively, a build surface MS, the same is applied to the below described description) in the Z axis direction. Namely, the head driving system  32  may change the distance DS so that the distance DS is zero. In this case, as illustrated in  FIG.  8 A  that is a planar view illustrating the processing lights EL# 1  to EL# 4  with which the workpiece W is irradiated and  FIG.  8 B  that is a cross-sectional view illustrating the processing lights EL# 1  to EL# 4  with which the workpiece W is irradiated, the processing lights EL# 1  to EL# 4  are condensed on the surface WS of the workpiece W. Namely, the processing lights EL# 1  to EL# 4  are overlapped with one another on the surface WS of the workpiece W. In this case, a single beam spot that is irradiated with the processing lights EL# 1  to EL# 4  is formed on the surface WS of the workpiece W. 
     The head driving system  32  may change the distance DS between the condensed plane FP and the surface WS of the workpiece W in the Z axis direction so that the condensed plane FP of the condensing optical system  3111  is away from the surface WS of the workpiece W in the Z axis direction. Namely, the head driving system  32  may change the distance DS so that the distance DS is a value that is different from zero. In this case, as illustrated in  FIG.  9 A  that is a planar view illustrating the processing lights EL# 1  to EL# 4  with which the workpiece W is irradiated and  FIG.  9 B  that is a cross-sectional view illustrating the processing lights EL# 1  to EL# 4  with which the workpiece W is irradiated, the processing lights EL# 1  to EL# 4  are not condensed on the surface WS of the workpiece W. Namely, the processing lights EL# 1  to EL# 4  are not overlapped with one another on the surface WS of the workpiece W. In this case, four single beam spots that are irradiated with the processing lights EL# 1  to EL# 4 , respectively, are formed on the surface WS of the workpiece W. A positional relationship between the four beam spots and sizes of the four beam spots vary depending on the distance between the condensed plane of the condensing optical system  3111  and the surface of the workpiece W in the Z axis direction. Note that the four beam spots are not overlapped with one another in an example illustrated in  FIG.  9 A , however, at least two of the four beam spots may be partially overlapped with each other. Moreover, the processing lights EL# 1  to EL# 4  do not intersect with one another in the example illustrated in  FIG.  9 A , however, the surface WS of the workpiece W may be irradiated with the processing lights EL# 1  to EL# 4  in a state the processing lights EL# 1  to EL# 4  are separated from one another after the processing lights EL# 1  to EL# 4  intersect with one another. 
     When the distance DS between the condensed plane FP of the condensing optical system  3111  and the surface WS of the workpiece W is changed in the Z axis direction in this manner, an irradiation state of the processing lights EL# 1  to EL# 4  on the surface WS of the workpiece W changes. As a result, a distribution (for example, an intensity distribution) of the processing lights EL# 1  to EL# 4  on the surface WS of the workpiece W changes. Thus, the head driving system  32  may serve as an apparatus that is configured to change the distribution (for example, the intensity distribution) of the processing lights EL# 1  to EL# 4  on the surface WS of the workpiece W. 
     Again in  FIG.  1    and  FIG.  2   , The stage apparatus  4  includes the stage  41  and a stage driving system  42 . However, the stage apparatus  4  may not include the stage driving system  42 . Note that the stage  41  may be referred to as a table. 
     The stage  41  is configured to support the workpiece W. Note that a state where “the stage  41  supports the workpiece W” here may mean a state where the workpiece W is directly or indirectly supported by the stage  41 . The stage  41  may be configured to hold the workpiece W placed on the stage  41 . Namely, the stage  41  may support the workpiece W by holding the workpiece W. In this case, the stage  41  may include a mechanical chuck, a vacuum chuck and the like in order to hold the workpiece W. Alternatively, the stage  41  may not be configured to hold the workpiece W. In this case, the workpiece W may be placed on the stage  41  without clamp. Furthermore, the stage  41  may be configured to release the held workpiece W, when the workpiece W is held. The above described irradiation optical system  311  irradiates the workpiece W with the processing lights EL# 1  to EL# 4  in at least a part of a period during which the stage  41  supports the workpiece W. Furthermore, the above described material nozzle  312  supplies the build materials M in at least a part of the period during which the stage  41  supports the workpiece W. 
     The stage driving system  42  is configured to move the stage  41 . Thus, the stage driving system  42  may be referred to as a movement apparatus. The stage driving system  42  moves the stage  41  along at least one of the X axis, the Y axis, the Z axis, the θX direction, the θY direction and the θZ direction for example. When the stage driving system  42  moves the stage  41 , a relative position between the processing head  31  and each of the stage  41  and the workpiece W placed on the stage  41  changes. Thus, the stage driving system  42  may serve as a movement apparatus that is configured to move the target irradiation area EA and the target supply area MA (furthermore, the melt pool MP) relative to the workpiece W, as with the head driving system  32 . Moreover, when the stage driving system  42  moves the stage  41  along the Z axis direction (namely, a direction along the optical axis AX of the condensing optical system  3111 ), the distance DS between the condensed plane FP of the condensing optical system  3111  on which the processing lights EL# 1  to EL# 4  are condensed and the surface WS of the workpiece W changes. Thus, the stage driving system  42  may serve as a movement apparatus that is configured to change the distance DS between the condensed plane FP of the condensing optical system  3111  and the surface WS of the workpiece W in the Z axis direction, as with the head driving system  32 . The stage driving system  42  may serve as an apparatus that is configured to change the distribution (for example, the intensity distribution) of the processing lights EL# 1  to EL# 4  on the surface WS of the workpiece W, as with the head driving system  32 . 
     The gas supply source  5  is a supply source of the purge gas for purging the chamber space  73 IN. The purge gas includes inert gas. The Nitrogen gas or Argon gas is one example of the inert gas. The gas supply source  5  is connected to the chamber space  73 IN through a supply port  72  formed at a wall member  71  of the housing  7  and a supply pipe  51  that connects the gas supply source  5  and the supply port  72 . The gas supply source  5  supplies the purge gas to the chamber space  73 IN through the supply pipe  51  and the supply port  72 . As a result, the chamber space  73 IN is a space that is purged by the purge gas. Note that the gas supply source  5  may be a tank that stores the inert gas such as the Nitrogen gas or the Argon gas. When the purge gas is the Nitrogen gas, the gas supply source  5  may be a Nitrogen gas generation apparatus that generates the Nitrogen gas by using air as material. 
     When the material nozzle  312  supplies the build materials M together with the purge gas, the gas supply source  5  may supply the purge gas to the mix apparatus  12  to which the build materials M are supplied from the material supply source  1 . Specifically, the gas supply source  5  may be connected to the mix apparatus  12  through a supply pipe  52  that connects the gas supply source  5  and the mix apparatus  12 . As a result, the gas supply source  5  supplies the purge gas to the mix apparatus  12  through the supply pipe  52 . In this case, the build materials M from the material supply source  1  may be supplied (specifically, pressure-fed) to the material nozzle  312  through the supply pipe  11  by the purge gas supplied from the gas supply source  5  through the supply pipe  52 . Namely, the gas supply source  5  may be connected to the material nozzle  312  through the supply pipe  52 , the mix apparatus  12  and the supply pipe  11 . In this case, the material nozzle  312  supplies, from the supply outlet  314 , the build materials M together with the purge gas for pressure-feeding the build materials M. 
     The control apparatus  6  is configured to control an operation of the processing system SYSa. The control apparatus  6  may include an arithmetic apparatus and a storage apparatus. The arithmetic apparatus may include at least one of a CPU (Central Processing Unit), a GPU (Graphic Processing Unit) and a FPGA (Field Programable Gate Array), for example. The storage apparatus may include a memory. The control apparatus  6  serves as an apparatus for controlling the operation of the processing system SYSa by means of the arithmetic apparatus executing a computer program. The computer program is a computer program that allows the arithmetic apparatus to execute (namely, to perform) a below described operation that should be executed by the control apparatus  6 . Namely, the computer program is a computer program that allows the control apparatus  6  to function so as to make the processing system SYSa execute the below described operation. The computer program executed by the arithmetic apparatus may be recorded in the storage apparatus (namely, a recording medium) of the control apparatus  6 , or may be recorded in any recording medium (for example, a hard disk or a semiconductor memory) that is built in the control apparatus  6  or that is attachable to the control apparatus  6 . Alternatively, the arithmetic apparatus may download the computer program that should be executed from an apparatus disposed at the outside of the control apparatus  6  through a network interface. 
     For example, the control apparatus  6  may control an emitting aspect of the processing lights EL# 1  to EL# 4  by the irradiation optical system  311 . The emitting aspect may include at least one of the intensities of the processing lights EL# 1  to EL# 4  and emitting timings of the processing lights EL# 1  to EL# 4 , for example. When the processing lights EL# 1  to EL# 4  include the pulsed light, the emitting aspect may include at least one of an ON time of the pulse light, an emission cycle of the pulse light and a ratio (what we call a duty ratio) of a length of the ON time of the pulse light and a length of the emission cycle of the pulse light, for example. Moreover, the control apparatus  6  may control a moving aspect of the processing head  31  by the head driving system  32 . Moreover, the control apparatus  6  may control a moving aspect of the stage  41  by the stage driving system  42 . The moving aspect may include at least one of a moving distance, a moving speed, a moving direction and a moving timing, for example. Moreover, the control apparatus  6  may control a supply aspect of the build materials M by the material nozzle  312 . The supply aspect may include at least one of the supplied amount (especially, the supplied amount per unit time) and a supply timing. 
     The control apparatus  6  may not be disposed in the processing system SYSa. For example, the control apparatus  6  may be disposed at the outside of the processing system SYSa as a server or the like. In this case, the control apparatus  6  may be connected to the processing system SYSa through a wired and/or wireless network (alternatively, a data bus and/or a communication line). A network using a serial-bus-type interface such as at least one of IEEE1394, RS-232x, RS-422, RS-423, RS-485 and USB may be used as the wired network. A network using a parallel-bus-type interface may be used as the wired network. A network using an interface that is compatible to Ethernet such as at least one of 10-BASE-T, 100BASE-TX or 1000BASE-T may be used as the wired network. A network using an electrical wave may be used as the wireless network. A network that is compatible to IEEE802.1x (for example, at least one of a wireless LAN and Bluetooth (registered trademark)) is one example of the network using the electrical wave. A network using an infrared ray may be used as the wireless network. A network using an optical communication may be used as the wireless network. In this case, the control apparatus  6  and the processing system SYSa may be configured to transmit and receive various information through the network. Moreover, the control apparatus  6  may be configured to transmit an information such as a command and a control parameter to the processing system SYSa through the network. The processing system SYSa may include a reception apparatus that is configured to receive the information such as the command and the control parameter from the control apparatus  6  through the network. The processing system SYSa may include a transmission apparatus that is configured to transmit the information such as the command and the control parameter to the control apparatus  6  through the network (namely, an output apparatus that is configured to output an information to the control apparatus  6 ). Alternatively, a first control apparatus that is configured to perform a part of the arithmetic processing performed by the control apparatus  6  may be disposed in the processing system SYSa and a second control apparatus that is configured to perform another part of the arithmetic processing performed by the control apparatus  6  may be disposed at an outside of the processing system SYSa 
     Note that at least one of an optical disc such as a CD-ROM, a CD-R, a CD-RW, a flexible disc, a MO, a DVD-ROM, a DVD-RAM, a DVD-R, a DVD+R, a DVD-RW, a DVD+RW and a Blu-ray (registered trademark), a magnetic disc such as a magnetic tape, an optical-magnetic disc, a semiconductor memory such as a USB memory, and another medium that is configured to store the program may be used as the recording medium recording therein the computer program that should be executed by the control apparatus  6  may include. Moreover, the recording medium may include a device that is configured to record the computer program (for example, a device for a universal use or a device for an exclusive use in which the computer program is embedded to be executable in a form of at least one of a software, a firmware and the like). Moreover, various arithmetic processing or functions included in the computer program may be realized by a logical processing block that is realized in the control apparatus  6  by means of the control apparatus  6  (namely, a computer) executing the computer program, may be realized by a hardware such as a predetermined gate array (a FPGA, an ASIC) of the control apparatus  6 , or may be realized in a form in which the logical process block and a partial hardware module that realizes an partial element of the hardware are combined. 
     The housing  7  is a housing apparatus that is configured to house at least a part of each of at least the processing apparatus  3  and the stage apparatus  4  in the chamber space  73 IN that is an internal space of the housing  7 . The housing  7  includes the wall member  71  that forms the chamber space  73 IN. The wall member  71  is a member that separates the chamber space  73 IN from the external space  74 OUT at the outside of the housing  7 . The wall member  71  faces the chamber space  73 IN through its inner wall  711  and faces the external space  74 OUT through its outer wall  712 . In this case, a space surrounded by the wall member  71  (more specifically, a space surrounded by the inner wall  711  of the wall member  71 ) is the chamber space  73 IN. Note that an openable and closable door may be disposed at the wall member  71 . The door may be opened when the workpiece W is to be placed on the stage  41 . The door may be opened when the workpiece W and/or a build object is unloaded from the stage  41 . The door may be closed during the processing (namely, during the additive processing or during a bonding processing). Note that an observation window (not illustrated) for visually observing the chamber space  73 IN from the external space  74 OUT of the housing  7  may be disposed at the wall member  71 . 
     (1-2) Operation of Processing System SYSa 
     Next, an operation of the processing system SYSa will be described. In the first example embodiment, the processing system SYSa performs an additive processing operation for forming the three-dimensional structural object ST on the workpiece W. Furthermore, the processing system SYSa performs a light characteristic control operation for controlling a characteristic of at least one of the processing light EL# 1  to the processing light EL# 4  in at least a part of a period during which the additive processing operation is performed. Thus, in the below described description, the additive processing operation and the light characteristic control operation will be described in order. 
     (2-1) Additive Processing Operation 
     Firstly, the additive processing operation will be described. As described above, the processing system SYSa forms the three-dimensional structural object ST by the Laser Metal Deposition. Thus, the processing system SYSa may form the three-dimensional structural object ST by performing an existing additive processing operation (a build operation in this case) based on the Laser Metal Deposition. Next, one example of the additive processing operation of forming the three-dimensional structural object ST by using the Laser Metal Deposition will be briefly described. 
     The processing system SYSa forms the three-dimensional structural object ST on the workpiece W based on a three-dimensional model data or the like (for example, a CAD (Computer Aided Design) data) of the three-dimensional structural object ST that should be formed. A measured data of the solid object measured by at least one of a non-illustrated measurement apparatus disposed in the processing system SYSa and a three-dimensional shape measurement device disposed separately from the processing system SYSa may be used as the three-dimensional model data. The processing system SYSa sequentially forms a plurality of layered partial structural objects (it is referred to as the “structural layer” in the below described description) SL that are arranged along the Z axis direction in order to form the three-dimensional structural object ST, for example. For example, the processing system 
     SYSa forms, one by one, the plurality of structural layers SL that are obtained by slicing the three-dimensional structural object ST along the Z axis direction. As a result, the three-dimensional structural object ST that is a layered structural body in which the plurality of structural layers SL are layered is formed. Next, a flow of an operation for forming the three-dimensional structural object ST by forming the plurality of structural layers SL one by one in sequence will be described. 
     Firstly, with reference to  FIG.  10 A  to  FIG.  10 E , an operation for forming each structural layer SL will be described. The processing system SYSa moves at least one of the processing head  31  and the stage so that the target irradiation areas EA are set at a desired area on the build surface MS that corresponds to a surface WS of the workpiece W or a surface of the formed structural layer SL, under the control of the control apparatus  6 . Then, the processing system SYSa emits the processing lights EL# 1  to EL# 4  from the irradiation optical system  311  to the target irradiation areas EA. In this case, the condensed plane FP on which the processing lights EL# 1  to EL# 4  are condensed may be located on the build surface MS in the Z axis direction (see  FIG.  8 A  to  FIG.  8 B ). Alternatively, the condensed plane FP on which the processing lights EL# 1  to EL# 4  are condensed may be away from the build surface MS in the Z axis direction (see  FIG.  9 A  to  FIG.  9 B ) When the build surface MS is irradiated with the processing lights EL# 1  to EL# 4 , as illustrated in  FIG.  10 A , the melt pool (namely, a pool of a metal molten by the processing lights EL# 1  to EL# 4 ) MP is formed on the build surface MS that is irradiated with the processing lights EL# 1  to EL# 4 . Moreover, the processing system SYSa supplies the build materials M from the material nozzle  312  under the control of the control apparatus  6 . Here, since the target irradiation area EA is coincident with the target supply area MA as described above, the target supply area MA includes at least a part of an area at which the melt pool MP is formed. Thus, the processing system SYSa supplies the build materials M to the melt pool MP from the material nozzle  312 , as illustrated in  FIG.  10 B . As a result, the build materials M supplied to the melt pool MP are molten. Then, when the melt pool MP is not irradiated with the processing light EL due to the movement of the processing head  31 , the build materials M molten in the melt pool MP are cooled and solidified (namely, coagulated). As a result, as illustrated in  FIG.  10 C , the solidified build materials M are deposited on the build surface MS. Namely, a build object is formed by a deposition of the solidified build materials M. 
     The processing system SYSa repeats a series of build process including the formation of the melt pool MP by the irradiation with the processing lights EL# 1  to EL# 4 , the supply of the build materials M to the melt pool MP, the melting of the supplied build materials M and the solidification of the molten build materials M while relatively moving the processing head  31  relative to the build surface MS along the XY plane, as illustrated in  FIG.  10 D . In this case, the processing system SYSa irradiates an area on the build surface MS on which the build object should be formed with the processing lights EL# 1  to EL# 4  and does not irradiate an area on the build surface MS on which the build object should not be formed with the processing lights EL# 1  to EL# 4 . Namely, the processing system SYSa moves the target irradiation areas EA along a predetermined moving trajectory on the build surface MS and irradiates the build surface MS with the processing lights EL# 1  to EL# 4  at a timing based on an aspect of a distribution of the area on which the build object should be formed. As a result, the melt pool MP also moves on the build surface MS along a moving trajectory based on the moving trajectory of the target irradiation areas EA. Specifically, the melt pool MP is formed in series at a part that is irradiated with the processing lights EL# 1  to EL# 4  in the area along the moving trajectory of the target irradiation areas EA on the build surface MS. As a result, as illustrated in  FIG.  10 E , the structural layer SL that is an aggregation of the build object of the build materials M, which are solidified after being molten, is formed on the build surface MS. Namely, the structural layer SL that is an aggregation of the build object formed in a pattern based on the moving trajectory of the melt pool MP on the build surface MS (namely, the structural layer SL having a shape based on the moving trajectory of the melt pool MP in a planar view) is formed. Incidentally, when the target irradiation areas EA are set at the area on which the build object should not be formed, the processing system SYSa may irradiate the target irradiation areas EA with the processing lights EL# 1  to EL# 4  and stop the supply of the build materials M. Moreover, when the target irradiation areas EA are set at the area on which the build object should not be formed, the processing system SYSa may supply the build materials M to the target irradiation areas EA and irradiate the target irradiation areas EA with the processing lights EL# 1  to EL# 4  having an intensity by which the melt pool MP is not formed. 
     The processing system SYSa repeats the operation for forming the structural layer SL based on the three-dimensional model data under the control of the control apparatus  6 . Specifically, the control apparatus  6  firstly generates slice data by performing a slicing process on the three-dimensional model data by a layer pitch. Note that data obtained by modifying a part of the slice data based on a characteristic of the processing system SYSa may be used. The processing system SYSa performs a process for forming the first structural layer SL# 1  on the build surface MS that corresponds to the surface WS of the workpiece W based on the three-dimensional model data corresponding to the structural layer SL# 1  (namely, the slice data corresponding to the structural layer SL# 1 ). As a result, as illustrated in  FIG.  11 A , the structural layer SL# 1  is formed on the build surface MS. Then, the processing system SYSa sets the surface (namely, an upper surface) of the structural layer SL# 1  to be a new build surface MS and forms a second structural layer SL# 2  on the new build surface MS. In order to form the structural layer SL# 2 , firstly, the control apparatus  6  controls the head driving system  32  so that the processing head  31  moves along the Z axis direction. Specifically, the control apparatus  6  controls the head driving system  32  to move the processing head  31  toward the +Z axis side so that the target irradiation area EA and the target supply area MA are set on the surface of the structural layer SL# 1  (namely, the new build surface MS). Then, the processing system SYSa performs a process for forming the structural layer SL# 2  on the structural layer SL# 1  based on the slice data corresponding to the structural layer SL# 2 , as with the process for forming the structural layer SL# 1  under the control of the control apparatus  6 . As a result, as illustrated in  FIG.  11 B , the structural layer SL# 2  is formed. Then, the same process is repeated until all structural layers SL constituting the three-dimensional structural object ST that should be formed on the workpiece W are formed. As a result, the three-dimensional structural object ST is formed by a layered structural object in which the plurality of structural layers SL are layered, as illustrated in  FIG.  11 C . 
     (1-2-2) Light Characteristic Control Operation 
     Next, the light characteristic control operation will be described. The light characteristic control operation is mainly performed under the control of the control apparatus  6 . Namely, the control apparatus  6  may control (in other words, change or adjust) the characteristic of at least one of the processing lights EL# 1  to EL# 4  by performing the light characteristic control operation in at least a part of the period during which the additive processing operation is performed. 
     The control apparatus  6  may control the characteristic of at least one of the processing lights EL# 1  to EL# 4  individually. Namely, the control apparatus  6  may control the characteristic of one processing light EL of the processing lights EL# 1  to EL# 4  regardless of whether or not the characteristic of another processing light EL of the processing lights EL# 1  to EL# 4  is controlled. In this case, the control apparatus  6  may control the characteristic of each of the processing lights EL# 1  to EL# 4 . Namely, the control apparatus may control the characteristic of the processing light EL# 1 , may control the characteristic of the processing light EL# 2 , may control the characteristic of the processing light EL# 3 , and may control the characteristic of the processing light EL# 4 . On the other hand, the control apparatus  6  may control the characteristic of at least one of the processing lights EL# 1  to EL# 4  and may not control the characteristic of at least another one of the processing lights EL# 1  to EL# 4 . Namely, the control apparatus  6  may control the characteristic of at least one of the processing lights EL# 1  to EL# 4  and may fix the characteristic of at least another one of the processing lights EL# 1  to EL# 4 . For example, the control apparatus  6  may control the characteristic of each of the processing lights EL# 1  and EL# 2  and may not control (may fix) the characteristic of each of the processing lights EL# 3  and EL# 4 . 
     The control apparatus  6  may control the characteristic of at least one of the processing lights EL# 1  to EL# 4  so that the characteristic of at least one of the processing lights EL# 1  to EL# 4  is different from the characteristic of at least another one of the processing lights EL# 1  to EL# 4 . In other words, the control apparatus  6  may be configured to set (in other words, determine) the characteristic of at least one of the processing lights EL# 1  to EL# 4  so that the characteristic of at least one of the processing lights EL# 1  to EL# 4  is different from the characteristic of at least another one of the processing lights EL# 1  to EL# 4 . In this case, the control apparatus  6  may control the characteristic of at least one of the processing lights EL# 1  to EL# 4  so that the characteristic of at least one of the processing lights EL# 1  to EL# 4  is the set characteristic. For example, the control apparatus  6  may set the characteristic of the processing light EL# 1  so that the characteristic of the processing light EL# 1  is different from the characteristic of each of the processing lights EL# 2  to EL# 4 , and may control the characteristic of the processing light EL# 1  so that the characteristic of the processing light EL# 1  is the set characteristic. 
     The characteristic of the processing light EL may include the intensity of the processing light EL. In this case, the control apparatus  6  may control the intensity of at least one of the processing lights EL# 1  to EL# 4 . Note that “the intensity of the processing light EL” here may mean an intensity of the processing light EL in a plane that intersects with the propagating direction of the processing light EL. Typically, “the intensity of the processing light EL” here may mean an intensity of the processing light EL on the build surface MS (for example, the surface WS of the workpiece W or the surface of the structural layer SL) on which the additive processing is actually performed. 
     The characteristic of the processing light EL may include the intensity distribution of the processing light EL. In this case, the control apparatus  6  may control the intensity distribution of at least one of the processing lights EL# 1  to EL# 4 . Note that “the intensity distribution of the processing light EL” here may mean an intensity of the processing light EL in a plane that intersects with the propagating direction of the processing light EL. Typically, “the intensity distribution of the processing light EL” here may mean an intensity distribution of the processing light EL on the build surface MS (for example, the surface WS of the workpiece W or the surface of the structural layer SL) on which the additive processing is actually performed. 
     The characteristic of the processing light EL may include a polarization distribution of the processing light EL. Namely, the characteristic of the processing light EL may include a distribution of a polarized light component (for example, a distribution of the polarized light component in a plane (typically, the build surface MS) that intersects with the propagating direction of the processing light EL) included in the processing light EL. The characteristic of the processing light EL may include a wavelength distribution of the processing light EL. Namely, the characteristic of the processing light EL may include a distribution of a light component (for example, a distribution of the light component in a plane (typically, the build surface MS) that intersects with the propagating direction of the processing light EL) in each wavelength or in each wavelength range included in the processing light EL. 
     When the characteristic (for example, at least one of the intensity and the intensity distribution) of the processing light EL is changed, a state (a formed state) of the melt pool MP formed by the processing light EL is changed. Thus, the control apparatus  6  may control the formed state of the melt pool MP by controlling the characteristic (for example, at least one of the intensity and the intensity distribution) of the processing light EL. The control apparatus  6  may control the formed state of the melt pool MP so that the formed state of the melt pool MP is a desired formed state (namely, an ideal formed state) by controlling the characteristic (for example, at least one of the intensity and the intensity distribution) of the processing light EL. 
     When the formed state of the melt pool MP is controlled, the control apparatus  6  may control the formed state of the melt pool MP based on a measured result by a measurement apparatus that is configured to measure the formed state of the melt pool MP. A measurement apparatus  82   b  of a processing system SYSb in a second example embodiment described below is one example of this type of measurement apparatus. However, the control apparatus  6  may control the formed state of the melt pool MP based on the measured result of the formed state of the melt pool MP by the measurement apparatus that is different from the measurement apparatus  82   b.    
     The formed state of the melt pool MP may include a temperature distribution of the melt pool MP. In this case, the control apparatus  6  may control the characteristic (for example, at least one of the intensity and the intensity distribution) of the processing light EL so that the temperature distribution of the melt pool MP is a desired temperature distribution (namely, an ideal temperature distribution). 
     When the temperature distribution of the melt pool MP is changed, there is a possibility that a size of the melt pool MP is changed. For example, when the temperature distribution of the melt pool MP is changed, there is a possibility that a size (namely, a width, a length) of the melt pool MP in a direction along the build surface MS is changed. For example, when the temperature distribution of the melt pool MP is changed, there is a possibility that a size (namely, a depth) of the melt pool MP in a direction intersecting with the build surface MS is changed. Thus, the formed state of the melt pool MP may include the size of the melt pool MP. In this case, the control apparatus  6  may control the characteristic (for example, at least one of the intensity and the intensity distribution) of the processing light EL so that the size of the melt pool MP is a desired size (namely, an ideal size). 
     In order to control the characteristic of at least one of the processing lights EL# 1  to EL# 4 , the control apparatus  6  may control at least one of the processing light sources  2 # 1  to  2 # 4  that generate the processing lights EL# 1  to EL# 4 , respectively. Specifically, the control apparatus  6  may control the characteristic of the processing light EL# 1  by controlling the processing light source  2 # 1 . The control apparatus  6  may control the characteristic of the processing light EL# 2  by controlling the processing light source  2 # 2 . The control apparatus  6  may control the characteristic of the processing light EL# 3  by controlling the processing light source  2 # 3 . The control apparatus  6  may control the characteristic of the processing light EL# 4  by controlling the processing light source  2 # 4 . 
     In order to control the characteristic of at least one of the processing lights EL# 1  to EL# 4 , the control apparatus  6  may control the distance DS in the Z axis direction between the condensed plane FP on which the condensing optical system  3111  condenses the processing lights EL# 1  to EL# 4  and the surface WS of the workpiece W. This is because the distribution (for example, the intensity distribution) of the processing lights EL# 1  to EL# 4  on the surface WS of the workpiece W (alternatively, the build surface MS) is changed when the distance DS is changed, as described above. Thus, the control apparatus  6  may control at least one of the head driving system  32  and the stage driving system  42  that are configured to change the distance DS so that the characteristic of at least one of the processing lights EL# 1  to EL# 4  is the desired characteristic by controlling the distance DS. 
     In order to control the characteristic of at least one of the processing lights EL# 1  to EL# 4 , the control apparatus  6  may control an optical member that is included in the irradiation optical system  311  and that is configured to control the characteristic of at least one of the processing lights EL# 1  to EL# 4 . 
     The control apparatus  6  may control the characteristic of at least one of the processing lights EL# 1  to EL# 4  based on a movement information related to the movement of the target irradiation areas EA on the build surface MS. Here, the target irradiation area EA moves due to the movement of the processing head  31  by the head driving system  32  and the movement of the stage  41  by the stage driving system  42  as described above. Thus, an operation for controlling the characteristic of at least one of the processing lights EL# 1  to EL# 4  based on the movement information related to the movement of the target irradiation areas EA may be regarded to be equivalent to an operation for controlling the characteristic of at least one of the processing lights EL# 1  to EL# 4  based on an information related to the movement of at least one of the processing head  31  and the stage  41 . 
     The movement information related to the movement of the target irradiation areas EA may include an information related to a moving direction of the target irradiation areas EA (namely, a moving direction of the irradiation positions of the processing lights EL# 1  to EL# 4 ) on the build surface MS. In this case, the control apparatus  6  may control the characteristic of at least one of the processing lights EL# 1  to EL# 4  based on the moving direction of the target irradiation areas EA on the build surface MS. The control apparatus  6  may control the characteristic of at least one of the processing lights EL# 1  to EL# 4  based on a moving direction of at least one of the processing head  31  and the stage  41 . 
     When the characteristic of at least one of the processing lights EL# 1  to EL# 4  is controlled based on the moving direction of the target irradiation areas EA on the build surface MS, the control apparatus  6  may control the characteristic of at least one of the processing lights EL# 1  to EL# 4  so that the characteristic of at least one processing light EL with which a position at a relatively front side along the moving direction is irradiated is different from the characteristic of at least one processing light EL with which a position at a relatively rear side along the moving direction is irradiated. For example,  FIG.  12    is a planar view that illustrates the target irradiation areas EA (namely, irradiation positions of the processing lights EL# 1  to EL# 4 ) moving toward the +Y side along the Y axis direction on the build surface MS. In an example illustrated in  FIG.  12   , the irradiation position of the processing light EL# 2  is located at the relatively front side (namely, the +Y side) along the moving direction of the target irradiation areas EA and the irradiation position of the processing light EL# 1  is located at the relatively rear side (namely, the −Y side) along the moving direction of the target irradiation areas EA. In this case, the control apparatus  6  may control the characteristic of at least one of the processing lights EL# 1  and EL# 2  so that the characteristic of the processing light EL# 1  is different from the characteristic of the processing light EL# 2 . 
     As one example, as illustrated in  FIG.  13 A  and  FIG.  13 B  each of which is a graph illustrating the intensities of the processing light EL# 1  with which the position at the relatively rear side along the moving direction is irradiated and the processing light EL# 2  with which the position at the relatively front side along the moving direction is irradiated, the control apparatus  6  may control the characteristic (for example, the intensity or the intensity distribution) of at least one of the processing lights EL# 1  and EL# 2  so that the intensity of the processing light EL# 1  is lower than the intensity of the processing light EL# 2 . Note that  FIG.  13 A  illustrates an example in which the intensity of the processing light EL# 1  is higher than zero and  FIG.  13 B  illustrates an example in which the intensity of the processing light EL# 1  is zero. When the intensity of the processing light EL# 1  with which the position at the relatively rear side along the moving direction is irradiated is lower than the intensity of the processing light EL# 2  with which the position at the relatively front side along the moving direction is irradiated in this manner, the formed state of the melt pool MP is kept to be the desired formed condition more easily. For example, the formed state of the melt pool MP is kept in a liquid phase state that is one example of the desired formed condition more easily. Therefore, the processing system SYSa is capable of properly processing the workpiece W. 
     As another example, as illustrated in  FIG.  14    that is a graph illustrating the intensities of the processing light EL# 1  with which the position at the relatively rear side along the moving direction is irradiated and the processing light EL# 2  with which the position at the relatively front side along the moving direction is irradiated, the control apparatus  6  may control the characteristic (for example, the intensity or the intensity distribution) of the processing light 
     EL# 1  so that the processing light EL# 1  is the pulsed light. On the other hand, the control apparatus  6  may control the characteristic (for example, the intensity or the intensity distribution) of the processing light EL# 2  so that the processing light EL# 2  is the continuous light (CW: Continuous Wave). When the processing light EL# 1  with which the position at the relatively rear side along the moving direction is irradiated is the pulsed light and the processing light EL# 2  with which the position at the relatively front side along the moving direction is irradiated is the continuous light, a processed mark of the build surface MS by the processing light EL# 2  is smoothed by the processing light EL# 2  that is the pulsed light. Therefore, the processing system SYSa is capable of properly processing the workpiece W. For example, the processing system SYSa is capable of forming the three-dimensional structural object ST the surface of which is relatively smooth. Moreover, the control apparatus  6  may control at least one of the processing light EL# 1  and the processing light EL# 2  so that an integrated value of a light intensity of the processing light EL# 1  is different from an integrated value of a light intensity of the processing light EL# 2 . 
     The control apparatus  6  may control the characteristic of at least one of the processing lights EL# 1  to EL# 4  based on a workpiece information related to the workpiece W that is a processing target, in addition to or instead of the above described movement information. The workpiece information related to the workpiece W may include an information related to a shape of the workpiece W. In this case, the control apparatus  6  may control the characteristic of at least one of the processing lights EL# 1  to EL# 4  based on the shape of the workpiece W. Incidentally, when a part of the three-dimensional structural object ST has been already formed on the workpiece W, the information related to the shape of the workpiece W may include an information related to the shape of the workpiece W including a part of the three-dimensional structural object ST already formed. 
     The control apparatus  6  may control the characteristic (for example, the intensity or the intensity distribution) of at least one of the processing lights EL# 1  to EL# 4  based on the shape of the workpiece W so that the intensity of the processing light EL with which a part of the workpiece W that should be processed is irradiated is equal to or higher than a processable intensity that is so high that the workpiece W is processed. The control apparatus  6  may control the characteristic (for example, the intensity or the intensity distribution) of at least one of the processing lights EL# 1  to EL# 4  based on the shape of the workpiece W so that the intensity of the processing light EL with which a part of the workpiece W that should not be processed is irradiated is equal to or lower than a un-processable intensity that is so low that the workpiece W is not processed. For example,  FIG.  15 A  is a cross-sectional view that illustrates an aspect in which the processing lights EL# 1  and EL# 2  are emitted toward the target irradiation areas EA in a situation where the target irradiation areas EA are set on a first part P 1  in order to process the first part P 1  of the build surface MS. In the situation illustrated in  FIG.  15 A , the first part P 1  of the workpiece W that should be processed is irradiated with each of the processing lights EL# 1  and EL# 2 . Thus, in this case, the control apparatus  6  may control the characteristic (for example, the intensity or the intensity distribution) of each of the processing lights EL# 1  and EL# 2  so that the intensity of each of the processing lights EL# 1  and EL# 2  is equal to or higher than the processable intensity. On the other hand,  FIG.  15 B  is a cross-sectional view that illustrates an aspect in which the processing lights EL# 1  and EL# 2  are emitted toward the target irradiation areas EA in a situation where the target irradiation areas 
     EA are set on a second part P 2  in order to process the second part P 2  of the build surface MS. In the situation illustrated in  FIG.  15 B , the second part P 2  of the workpiece W that should be processed is irradiated with the processing light EL# 2 . Thus, in this case, the control apparatus  6  may control the characteristic (for example, the intensity or the intensity distribution) of the processing light EL # 2  so that the intensity of the processing light EL# 2  is equal to or higher than the processable intensity. On the other hand, the second part P 2  of the workpiece W that should be processed is not irradiated with the processing light EL# 1 . This is because a third part P 3  of the workpiece W that should not be processed exists on the optical path of the processing light EL# 1  from the irradiation optical system  211  to the target irradiation area EA. In this case, if the third part P 3  is irradiated with the processing light EL# 1 , there is a possibility that the third part P 3  is unintentionally processed. Thus, the control apparatus  6  may control the characteristic (for example, the intensity or the intensity distribution) of the processing light EL# 1  so that the intensity of the processing light EL# 1  is equal to or lower than the un-processable intensity. In this case, the control apparatus  6  may perform the control so that the intensity of the processing light EL # 1  is zero. As a result, the processing system SYSa is capable of properly processing the workpiece W. 
     (1-3) Technical Effect of Processing System SYSa 
     As described above, the processing system SYSa in the first example embodiment is capable of individually controlling at least one of the plurality of processing lights EL with which the workpiece W is irradiated. Thus, the processing system SYSa is capable of processing the workpiece W more properly by using the plurality of processing lights EL, compared to a processing system in a comparison example that is not capable of individually controlling at least one of the plurality of processing lights EL. 
     (1-4) Modified Example of Processing Light EL 
     In the above described example illustrated in  FIG.  5   , the processing lights EL# 1  to EL# 4  pass through the areas that are rotationally symmetric about the optical axis AX and that are away from the optical axis AX toward the different directions in the virtual optical plane OP (for example, the incident pupil plane of the condensing optical system  3111 ) in the condensing optical system  3111  that intersects with the optical axis AX of the condensing optical system  3111 . However, as illustrated in  FIG.  16    that is a cross-sectional view illustrating the optical paths of the processing lights EL# 1  to EL# 4  in the optical plane OP, the processing lights EL# 1  to EL# 4  may pass through areas that are rotationally asymmetric about the optical axis AX and that are away from the optical axis AX toward the different directions in the optical plane OP. In other words, the areas through which the processing lights EL# 1  to EL# 4  pass in the optical plane OP may be  1 -fold rotationally symmetric about the optical axis AX. For example, the processing lights EL# 1  to EL# 4  may pass through different areas that are not line-symmetric in a situation where a straight line intersecting with the optical axis AX (for example, a straight line along the X axis or the Y axis) is a symmetrical axis in the optical plane OP. In this case, there is a smaller possibility that a returned light of one processing light EL, with which the workpiece W is irradiated, from the workpiece W enter the processing light source  2  that generates another processing light EL through an optical path that is same as an optical path of another processing light EL with which the workpiece W is irradiated. Thus, there is a smaller possibility that the processing light source  2  gets out of order due to the returned light entering the processing light source  2 . 
     Moreover, In the above described example illustrated in  FIG.  8    and  FIG.  9   , a shape of the beam spot formed by the processing light EL on the build surface MS (for example, the surface WS of the workpiece W or the surface of the structural layer SL) is a circular shape. However, the shape of the beam spot formed by the processing light EL may be a shape that is different from the circular shape. For example, the shape of the beam spot formed by the processing light EL may be an oval shape, a rectangular shape or a slit-shape. Moreover, the plurality of processing lights EL may form the beam spot having a desired shape. For example, as illustrated in  FIG.  17    that is a planar view illustrating one example of the beam spot having the desired shape formed by the plurality of processing lights EL on the build surface MS, the plurality of processing lights EL may form the beam spot having a ring shape on the build surface MS. In this case, each processing light EL may form a beam spot having an arc-shape (a partial ring shape) that is a part of the ring on the build surface MS. 
     (2) Processing System SYS in Second Example Embodiment 
     Next, with reference to  FIG.  18    and  FIG.  19   , the processing system SYS in a second example embodiment (hereinafter, the processing system SYS in the second example embodiment is referred to as a “processing system SYSb”) will be described.  FIG.  18    is a cross-sectional view that conceptionally illustrates one example of the configuration of the processing system SYSb in the second example embodiment.  FIG.  19    is a system configuration diagram that illustrates a system configuration of the processing system SYSb in the second example embodiment. 
     As illustrated in  FIG.  18    and  FIG.  19   , the processing system SYSb in the second example embodiment is different from the above described processing system SYSa in the first example embodiment in that it includes a measurement light source  81   b  and a measurement apparatus  82   b . Another feature of the processing system SYSb may be same as another feature of the processing system SYSa. 
     The measurement light sources  81   b  is configured to emit at least one of an infrared light, a visible light and a ultraviolet light as a measurement light ML, for example. However, another type of emission (for example, at least one of a Terahertz wave, a microwave, a X-ray and so on) may be used as the measurement light ML. A wavelength of the measurement light ML may be different from a wavelength of the processing light EL. A wavelength range of the measurement light ML may be different from a wavelength range of the processing light EL. However, the wavelength of the measurement light ML may be same as the wavelength of the processing light EL. At least a part of the wavelength range of the measurement light ML may be superimposed with (namely, overlapped with) at least a part of the wavelength range of the processing light EL. The measurement light ML emitted from the measurement light source  81   b  enters the irradiation optical system  311  through a light transmission member  811   b  including at least one of an optical fiber, a light pipe and so on. Thus, the irradiation optical system  311  is optically connected to the measurement light source  81   b  through the light transmission member  811   b . The workpiece W (more specifically, the build surface MS) is irradiated with the measurement light ML, which has entered the irradiation optical system  311 , through the irradiation optical system  311  (namely, through the condensing optical system  3111 ). In this case, the measurement light ML may be used as an illumination light for illuminating the workpiece W. In this case, the measurement light source  81   b  may be referred to as an illumination apparatus. 
     The irradiation optical system  311  may irradiate an area, which is irradiated with at least one of the processing lights EL# 1  to EL# 4  on the workpiece W, with the measurement light ML. The irradiation optical system  311  may irradiate an area, which includes at least a part of the target irradiation area EA set on the workpiece W, with the measurement light ML. 
     The irradiation optical system  311  may irradiate an area, which includes at least a part of the melt pool MP formed on the workpiece W, with the measurement light ML. However, the irradiation optical system  311  may irradiate an area, which is different from the area irradiated with at least one of the processing lights EL# 1  to EL# 4  on the workpiece W, with the measurement light ML. The irradiation optical system  311  may irradiate an area, which is different from the area including at least a part of the target irradiation area EA set on the workpiece W, with the measurement light ML. The irradiation optical system  311  may irradiate an area, which is different from the area including at least a part of the melt pool MP formed on the workpiece W, with the measurement light ML. 
     When the workpiece W is irradiated with the measurement light ML, a returned light generated by irradiating the workpiece W with the measurement light ML is emitted from the workpiece W. The returned light may include at least one of a reflected light, a scattered light and a transmitted light of the measurement light ML by the workpiece W. Note that the returned light may be referred to as a light that is directly generated by irradiating the workpiece W with the measurement light ML. Moreover, the melt pool MP formed by the molten metal molten is formed on the workpiece W as described above. In this case, from the workpiece W, a light from the melt pool MP (a light that is indirectly generated by the irradiation with the processing lights EL) is emitted from the workpiece W. Hereinafter, both of the returned light that is directly generated by irradiating the workpiece W with the measurement light ML and the light that is indirectly generated by the irradiation with the processing lights EL will be referred to as an object light RL. A wavelength of the object light RL (especially, a wavelength of the returned light included in the object light RL) may be different from the wavelength of the processing light EL. A wavelength range of the object light RL may be different from the wavelength range of the processing light EL. The wavelength of the object light RL may be same as the wavelength of the processing light EL. At least a part of the wavelength range of the object light RL may be overlapped with at least a part of the wavelength range of the processing light EL. The object light RL emitted from the workpiece W enters the measurement apparatus  82   b  through the irradiation optical system  311  (namely, through the condensing optical system  3111 ). 
     Here, with reference to  FIG.  20    and  FIG.  21   , optical paths of the measurement light ML and the object light RL in the irradiation optical system  311  (especially, in the condensing optical system  3111 ) will be described.  FIG.  20    is a cross-sectional view that illustrates the optical paths of the measurement light ML and the object light RL in the irradiation optical system  311  (especially, in the condensing optical system).  FIG.  21    is a XX-XX′ cross-sectional view of  FIG.  20   . Note that  FIG.  20    is a XX-XX′ cross-sectional view of  FIG.  21   . 
     As illustrated in  FIG.  20    and  FIG.  21   , at least a part of the optical path of the measurement light ML, at least a part of the optical path of the object light RL and at least a part of the optical paths of the processing lights EL# 1  to EL# 4  may be optically separated from one another other in the condensing optical system  3111 . Namely, at least a part of the optical path of the measurement light ML, at least a part of the optical path of the object light RL and at least a part of the optical paths of the processing lights EL# 1  to EL# 4  may be different from one another other in the condensing optical system  3111 . At least a part of the optical path of the measurement light ML, at least a part of the optical path of the object light RL and at least a part of the optical paths of the processing lights EL# 1  to EL# 4  may not be overlapped with one another other in the condensing optical system  3111 . 
     In order to optically separate at least a part of the optical path of the measurement light ML, at least a part of the optical path of the object light RL and at least a part of the optical paths of the processing lights EL# 1  to EL# 4 , as illustrated in  FIG.  21   , the measurement light ML, the object light RL and the processing lights EL# 1  to EL# 4  may pass through different areas, respectively, that are away from the optical axis AX toward different directions in the virtual optical plane OP (typically, the plane along the XY plane, and the pupil plane (the incident pupil plane) of the condensing optical system  3111 , for example) in the condensing optical system  3111  that intersects with the optical axis AX of the condensing optical system  3111 . An area through which the measurement light ML passes, an area through which the object light RL passes and areas through which the processing lights EL# 1  to EL# 4  pass may not be overlapped from one another in the optical plane OP. In this case, a distance between the optical axis AX and the optical path of the measurement light ML, a distance between the optical axis AX and the optical path of the object light RL, the distance between the optical axis AX and the optical path of the processing light EL# 1 , the distance between the optical axis AX and the optical path of the processing light EL# 2 , the distance between the optical axis AX and the optical path of the processing light EL# 3  and the distance between the optical axis AX and the optical path of the processing light EL# 4  may be equal to one another in the optical plane OP. Alternatively, the distances between the optical axis AX and the optical paths of at least two of the measurement light ML, the object light RL and the processing lights EL# 1  to EL# 4  may be different from each other. In an example illustrated in  FIG.  21   , the distances between the optical axis AX and the optical paths of the measurement light ML, the object light RL and the processing lights EL# 1  to EL# 4  are equal to one another in the optical plane OP. In this case, the measurement light ML, the object light RL and the processing lights EL# 1  to EL# 4  may pass through areas that are line symmetric with respect to a J axis that intersects with the optical axis AX in the optical plane OP. For example, as illustrated in  FIG.  21   , the measurement light ML, the object light RL and the processing lights EL# 1  to EL# 4  may pass through six areas whose rotational angles along the clockwise direction around the origin are 315 degree, 135 degree, 270 degree, 90 degree, 0 degree and 180 degree (alternatively, θ+α degree (note that α is any angle that is different from 90 degree, 180 degree and 270 degree), θ+α-180 degree, θ+270 degree, θ+90 degree, θ degree and θ+180 degree) in the coordinate plane along the XY plane the origin of which is the optical axis AX. In other words, the measurement light ML, the object light RL and the processing lights EL# 1  to EL# 4  may pass through areas that are 2-fold rotationally symmetric about the optical axis AX in the optical plane OP. 
     When the measurement light ML, the object light RL and the processing lights EL# 1  to EL# 4  pass through the different areas, respectively, that are away from the optical axis AX toward the different directions in the optical plane OP, the condensing optical system  3111  may emit the measurement light ML and the processing lights EL# 1  to EL# 4  toward the workpiece W from different directions. Specifically, as illustrated in  FIG.  21   , the condensing optical system  3111  may emit the measurement light ML and the processing lights EL# 1  to EL# 4  toward the workpiece W from positions that are different from one another along a rotational direction around the optical axis AX. Moreover, the object light RL may pass through the optical path that is different from the optical paths through which the processing lights EL# 1  to EL# 4  pass between the condensing optical system  3111  and the workpiece W and then enter the condensing optical system  3111 . 
     Alternatively, in order to optically separate at least a part of the optical path of the measurement light ML, at least a part of the optical path of the object light RL and at least a part of the optical paths of the processing lights EL# 1  to EL# 4 , the measurement light ML, the object light RL and the processing lights EL# 1  to EL# 4  may pass through different areas, respectively, that are away from the optical axis AX toward same direction by different distances in the optical plane OP. In this case, the condensing optical system  3111  may irradiate the workpiece W with the measurement light ML and the processing lights EL# 1  to EL# 4  so that an angle between the optical axis AX and a propagating direction of the measurement light ML and the angles between the optical axis AX and the propagating directions of the processing lights EL# 1  to EL# 4  are different from one another between the condensing optical system  3111  and the workpiece W. Moreover, the object light RL propagate along an optical path that allows an angle between the optical axis AX and a propagating direction of the object light RL and the angles between the optical axis AX and the propagating directions of the processing lights EL# 1  to EL# 4  to be different from one another between the condensing optical system  3111  and the workpiece W, and then enter the condensing optical system  3111 . 
     The object light RL entering the condensing optical system  3111  (namely, through at least a part of the irradiation optical system  311 ) is detected (in other words, optically received) by the measurement apparatus  82   b . Thus, the measurement apparatus  82   b  may be referred to as a detection apparatus or a light reception apparatus. Moreover, the measurement apparatus  82   b  may be referred to as an information obtaining apparatus that is configured to obtain an information related to the object light RL. The measurement apparatus  82   b  is configured to measure (in other words, observe or monitor) the workpiece W by detecting the object light RL. As one example, the measurement apparatus  82   b  may include an imaging apparatus (a camera) that is configured to capture an image of the workpiece W by detecting the object light RL. In this case, the measurement apparatus  82   b  may measure the workpiece W by capturing the image of at least a part of the workpiece W that is irradiated with the measurement light ML that is usable as the illumination light. 
     A detected result of the object light RL (namely, a measured result of the workpiece W) by the measurement apparatus  82   b  is outputted to the control apparatus  6 . The control apparatus  6  may control the processing system SYSb so as to process the workpiece W based on the detected result of the object light RL by the measurement apparatus  82   b.    
     The above described processing system SYSb in the second example embodiment is capable of achieving an effect that is same as an effect achievable by the above described processing system SYSa in the first example embodiment. Furthermore, the processing system SYSb is capable of processing the workpiece W based on the measured result of the workpiece W by the measurement apparatus  82   b . Thus, the processing system SYSb is capable of processing the workpiece W more properly, compared to a processing system in a comparison example that does not include the measurement apparatus  82   b . For example, when the workpiece W is irradiated with the measurement light ML before the additive processing operation is started, the processing system SYSb may determine a state of the workpiece W that is not yet processed based on the measured result of the workpiece W by the measurement apparatus  82   b . As a result, the processing system SYSb may properly set a processing condition based on the state of the workpiece W that is not yet processed so that the proper additive processing operation is performed. For example, when the workpiece W is irradiated with the measurement light ML during a period during which the additive processing operation is performed, the processing system SYSb may determine a processed state of the workpiece Win real-time based on the measured result of the workpiece W by the measurement apparatus  82   b . As a result, the processing system SYSb may properly set the processing condition based on the processed state of the workpiece W that is determined in real -time so that the proper additive processing operation is performed. For example, when the workpiece W is irradiated with the measurement light ML after the additive processing operation ends, the processing system SYSb may determine the state of the workpiece W that is has been already processed based on the measured result of the workpiece W by the measurement apparatus  82   b . As a result, the processing system SYSb may determine based on the state of the workpiece W that has been already processed whether or not the proper additive processing operation is performed. Furthermore, when it is determined that the proper additive processing operation is not performed, the processing system SYSb may process the workpiece W again. 
     (3) Processing System SYS in Third Example Embodiment 
     Next, with reference to  FIG.  22   , the processing system SYS in a third example embodiment (hereinafter, the processing system SYS in the third example embodiment is referred to as a “processing system SYSc”) will be described.  FIG.  22    is a system configuration diagram that illustrates a system configuration of the processing system SYS c in the third example embodiment. 
     As illustrated in  FIG.  22   , the processing system SYSb in the third example embodiment is different from the above described processing system SYSb in the second example embodiment in that it includes a processing apparatus  3   c  instead of the processing apparatus  3 . Another feature of the processing system SYSc may be same as another feature of the processing system SYSb. The processing apparatus  3   c  is different from the processing apparatus  3  in that it includes a processing head  31   c  instead of the processing head  31 . Another feature of the processing apparatus  3   c  may be same as another feature of the processing apparatus  3 . The processing head  31   c  is different from the processing head  31  in that it includes an irradiation optical system  311   c  instead of the irradiation optical system  311 . 
     Another feature of the processing head  31   c  may be same as another feature of the processing head  31 . Thus, next, with reference to  FIG.  23   , the irradiation optical system  311   c  will be described.  FIG.  23    is a cross-sectional view that illustrates a configuration of the irradiation optical system  311   c  in the third example embodiment. 
     As illustrated in  FIG.  23   , the irradiation optical system  311   c  is different from the irradiation optical system  311  in that it includes a movable mirrors  3115   c  and  3116   c  and a movable mirror driving apparatus  3117   c  and  3118   c . Another feature of the irradiation optical system  311   c  may be same as another feature of the irradiation optical system  311 . 
     The movable mirror  3115   c  is disposed on the optical path of the measurement light ML emitted from the measurement light source  81   b . In an example illustrated in  FIG.  23   , the movable mirror  3115   c  is disposed on the optical path of the measurement light ML between the measurement light source  81   b  and the condensing optical system  3111 . In this case, the movable mirror  3115   c  guides the measurement light ML to the condensing optical system  3111  by reflecting the measurement light ML entering a reflection surface of the movable mirror  3115   c . The movable mirror  3116   c  is disposed on the optical path of the object light RL emitted from the workpiece W. In the example illustrated in  FIG.  23   , the movable mirror  3116   c  is disposed on the optical path of the object light RL between the condensing optical system  3111  and the measurement apparatus  82   b . In this case, the movable mirror  3116   c  guides the object light RL to the measurement apparatus  82   b  by reflecting the object light RL entering a reflection surface of the movable mirror  3116   c.    
     The movable mirror  3115   c  is movable by the movable mirror driving apparatus  3117   c  so as to change an angle of the reflection surface of the movable mirror  3115   c  relative to the propagating direction of the measurement light ML entering the movable mirror  3115   c . The movable mirror  3116   c  is movable by the movable mirror driving apparatus  3118   c  so as to change an angle of the reflection surface of the movable mirror  3116   c  relative to the propagating direction of the object light RL entering the movable mirror  3116   c . The movable mirror driving apparatuses  3117   c  and  3118   c  are configured to change the angles of the reflection surfaces of the movable mirrors  3115   c  and  3116   c  under the control of the control apparatus  6 . 
     In the third example embodiment, for example, the movable mirror  3115   c  may change an irradiation position of the measurement light ML on the build surface MS by changing the angle of the reflection surface of the movable mirror  3115   c  relative to the propagating direction of the measurement light ML. Thus, the movable mirror  3115   c  and the movable mirror driving apparatus  3117   c  may serve as a position change apparatus that is configured to change the irradiation position of the measurement light ML on the build surface MS. Moreover, the movable mirror  3116   c  may guide, to the measurement apparatus  82   b , the object light RL including the returned light of the measurement light ML with which the build surface MS is irradiated by changing the angle of the reflection surface of the movable mirror  3116   c  relative to the propagating direction of the object light RL in synchronization with the movement of the movable mirror  3115   c . Namely, the movable mirror  3116   c  and the movable mirror driving apparatus  3118   c  may change the angle of the reflection surface of the movable mirror  3116   c  relative to the propagating direction of the object light RL so that the measurement apparatus  82   b  detects the object light RL including the returned light of the measurement light ML even when the irradiation position of the measurement light ML is changed on the build surface MS. 
     For example, as illustrated in  FIG.  24 A  that is a cross-sectional view illustrating a first example of the optical path of the measurement light ML with which the build surface MS is irradiated, the movable mirror  3115   c  may change the angle of the reflection surface of the movable mirror  3115   c  relative to the propagating direction of the measurement light ML so that a position on the build surface MS that is currently being irradiated with the processing lights EL is irradiated with the measurement light ML. Moreover, in this case, the movable mirror  3116   c  may change the angle of the reflection surface of the movable mirror  3116   c  relative to the propagating direction of the object light RL so that the object light RL including a light from the position on the build surface MS that is currently being irradiated with the processing lights EL enters the measurement apparatus  82   b . As a result, the processing system SYSc may determine the processed state of the workpiece W in real-time based on the measured result of the workpiece W by the measurement apparatus  82   b . Thus, the processing system SYSc may properly set the processing condition based on the processed state of the workpiece W that is determined in real-time so that the proper additive processing operation is performed. 
     For example, as illustrated in  FIG.  24 B  that is a cross-sectional view illustrating a second example of the optical path of the measurement light ML with which the build surface 
     MS is irradiated, the movable mirror  3115   c  may change the angle of the reflection surface of the movable mirror  3115   c  relative to the propagating direction of the measurement light ML so that a position on the build surface MS that has been already irradiated with the processing light EL is irradiated with the measurement light ML. Note that the position that has been already irradiated with the processing light EL is located at a rear side along the moving direction of the processing lights EL (namely, the moving direction of the target irradiation areas EA) in a direction along the build surface MS from the position that is currently being irradiated with the processing lights EL. Moreover, in this case, the movable mirror  3116   c  may change the angle of the reflection surface of the movable mirror  3116   c  relative to the propagating direction of the object light RL so that the object light RL including a light from the position on the build surface MS that has been already irradiated with the processing lights EL enters the measurement apparatus  82   b . As a result, the processing system SYSc may determine the state of the workpiece W that has been already processed based on the measured result of the workpiece W by the measurement apparatus  82   b . Thus, the processing system SYSc may properly determine based on the state of the workpiece W that has been already processed whether or not the proper additive processing operation is performed. 
     For example, as illustrated in  FIG.  24 C  that is a cross-sectional view illustrating a third example of the optical path of the measurement light ML with which the build surface MS is irradiated, the movable mirror  3115   c  may change the angle of the reflection surface of the movable mirror  3115   c  relative to the propagating direction of the measurement light ML so that a position on the build surface MS that is not yet irradiated with the processing lights EL (specifically, that is expected to be irradiated with the processing lights EL in the future) is irradiated with the measurement light ML. Note that the position that is expected to be irradiated with the processing lights EL in the future is located at a front side along the moving direction of the processing lights EL (namely, the moving direction of the target irradiation areas EA) in a direction along the build surface MS from the position that is currently being irradiated with the processing lights EL. Moreover, in this case, the movable mirror  3116   c  may change the angle of the reflection surface of the movable mirror  3116   c  relative to the propagating direction of the object light RL so that the object light RL including a light from the position on the build surface MS that is expected to be irradiated with the processing lights EL in the future enters the measurement apparatus  82   b . As a result, the processing system SYSc may determine the state of the workpiece W that is not yet processed based on the measured result of the workpiece W by the measurement apparatus  82   b . Thus, the processing system SYSc may properly set the processing condition based on the state of the workpiece W that is not yet processed so that the proper additive processing operation is performed. 
     As described above, the above described processing system SYSc in the third example embodiment is capable of achieving an effect that is same as the effect achievable by the above described processing system SYSb in the second example embodiment. 
     Note that an effect that is same as the effect of the processing system SYSc in the third example embodiment is achievable by changing angles of the emitting ports of the light transmitting members  21 # 1  to  21 # 4  in the first example embodiment to there by change propagating directions of the processing lights EL# 1  to EL# 4  emitted from the light transmitting members  21 # 1  to  21 # 4 . 
     (4) Processing System SYS in Fourth Example Embodiment 
     Next, with reference to  FIG.  25   , the processing system SYS in a fourth example embodiment (hereinafter, the processing system SYS in the fourth example embodiment is referred to as a “processing system SYSd”) will be described.  FIG.  25    is a system configuration diagram that illustrates a system configuration of the processing system SYS d in the fourth example embodiment. 
     As illustrated in  FIG.  25   , the processing system SYSd in the fourth example embodiment is different from the above described processing system SYSb in the second example embodiment in that it includes a measurement apparatus  83   d . Another feature of the processing system SYSd may be same as another feature of the processing system SYSb. 
     The measurement apparatus  83   d  is an apparatus that is configured to measure the workpiece W, as with the measurement apparatus  82   b . However, the measurement apparatus  83   d  may be an apparatus that is configured to measure the workpiece W by using a measurement method different from that of the measurement apparatus  82   b . For example, when the measurement apparatus  82   b  measures the workpiece W by capturing the image of the workpiece W, the measurement apparatus  83   d  may be an apparatus that is configured to measure the workpiece W without capturing the image of the workpiece W. 
     The measurement apparatus  83   d  is an apparatus that is configured to optically measure the workpiece W through the condensing optical system (namely, through the irradiation optical system  311 ). In this case, the measurement apparatus  83   d  may include a light transmission part  831   d  and a light reception part  832   d.    
     The light transmission part  831   d  is configured to transmit a measurement light ML′ from a not-illustrated light source to the workpiece W through the condensing optical system  3111 , for example. Namely, the light transmission part  831   d  is configured to irradiate the workpiece W with the measurement light ML′ from the not-illustrated light source through the condensing optical system  3111 . Thus, the light transmission part  831   d  may be referred to as an irradiation apparatus. Note that the light transmission part  831   d  may include the light source of the measurement light ML′. The measurement light ML′ includes at least one of an infrared light, a visible light and a ultraviolet light, for example. However, the measurement light ML′ may include another type of emission (for example, at least one of a Terahertz wave, a microwave, a X-ray and so on). A wavelength of the measurement light ML′ may be different from the wavelength of at least one of the processing light EL and the measurement light ML. A wavelength range of the measurement light ML′ may be different from a wavelength range of at least one of the processing light EL and the measurement light ML. However, the wavelength of the measurement light ML′ may be same as the wavelength of at least one of the processing light EL and the measurement light ML. At least a part of the wavelength range of the measurement light ML′ may be superimposed with (namely, overlapped with) at least a part of the wavelength range of at least one of the processing light EL and the measurement light ML. 
     The irradiation optical system  311  may irradiate an area on the workpiece W that is currently being irradiated with at least one of the measurement light ML and the processing lights EL# 1  to EL# 4  with the measurement light ML′. The irradiation optical system  311  may irradiate an area including at least a part of the target irradiation areas EA set on the workpiece W with the measurement light ML′. The irradiation optical system  311  may irradiate an area including at least a part of the melt pool MP formed on the workpiece W with the measurement light ML′. However, the irradiation optical system  311  may irradiate an area, which is different from the on the workpiece W that is currently being irradiated with at least one of the measurement light ML and the processing lights EL# 1  to EL# 4 , with the measurement light ML′. The irradiation optical system  311  may irradiate an area, which is different from the area including at least a part of the target irradiation areas EA set on the workpiece W, with the measurement light ML′. The irradiation optical system  311  may irradiate an area, which is different from the area including at least a part of the melt pool MP formed on the workpiece W, with the measurement light ML′. 
     When the workpiece W is irradiated with the measurement light ML′, a returned light RL′ generated by irradiating the workpiece W with the measurement light ML′ is emitted from the workpiece W. The returned light RL′ may include at least one of a reflected light, a scattered light and a transmitted light of the measurement light ML′ by the workpiece W. The returned light RL′ emitted from the workpiece W (namely, an object light corresponding to the measurement light ML′ through the workpiece W) enters the light reception part  832   d  through the irradiation optical system (namely, through the condensing optical system  3111 ). 
     Here, with reference to  FIG.  26    and  FIG.  27   , optical paths of the measurement light ML′ and the returned light RL′ in the irradiation optical system  311  (especially, in the condensing optical system  3111 ) will be described.  FIG.  26    is a cross-sectional view that illustrates the optical paths of the measurement light ML′ and the returned light RL′ in the irradiation optical system  311  (especially, in the condensing optical system).  FIG.  27    is a XXVI-XXVI′ cross-sectional view of  FIG.  26   . 
     As illustrated in  FIG.  26    and  FIG.  27   , at least a part of the optical path of the measurement light ML′ may be optically separated from (namely, may be different from) at least a part of the optical paths of the measurement light ML, the object light RL and the processing lights EL# 1  to EL# 4  in the condensing optical system  3111 . Thus, as illustrated in  FIG.  27   , the measurement light ML′, the measurement light ML, the object light RL and the processing lights EL# 1  to EL# 4  may pass through different areas, respectively, that are away from the optical axis AX toward different directions in the virtual optical plane OP (typically, the plane along the XY plane, and the incident pupil plane of the condensing optical system  3111 , for example) in the condensing optical system  3111  that intersects with the optical axis AX of the condensing optical system  3111 . Alternatively, the measurement light ML′, the measurement light ML, the object light RL and the processing lights EL# 1  to EL# 4  may pass through different areas, respectively, that are away from the optical axis AX toward same direction by different distances in the optical plane OP (see  FIG.  6    and  FIG.  7   ). 
     As illustrated in  FIG.  26    and  FIG.  27   , at least a part of the optical path of the returned light RL′ may be optically separated from (namely, may be different from) at least a part of the optical paths of the measurement light ML, the object light RL and the processing lights EL# 1  to EL# 4  in the condensing optical system  3111 . Thus, as illustrated in  FIG.  27   , the returned light RL′, the measurement light ML, the object light RL and the processing lights EL# 1  to EL# 4  may pass through different areas, respectively, that are away from the optical axis AX toward different directions in the virtual optical plane OP (typically, the plane along the XY plane, and the incident pupil plane of the condensing optical system  3111 , for example) in the condensing optical system  3111  that intersects with the optical axis AX of the condensing optical system  3111 . Alternatively, the returned light RL′, the measurement light ML, the object light RL and the processing lights EL# 1  to EL# 4  may pass through different areas, respectively, that are away from the optical axis AX toward same direction by different distances in the optical plane OP (see  FIG.  6    and  FIG.  7   ). 
     On the other hand, the optical path of the measurement light ML′ and the optical path of the returned light RL′ may not be optically separated from each other in the condensing optical system  3111 . Namely, the optical path of the measurement light ML′ propagating from the light transmission part  831   d  to the workpiece W and the optical path of the returned light RL′ propagating from the workpiece W to the light reception part  832   d  may be overlapped with each other in the condensing optical system  3111 . Thus, as illustrated in  FIG.  27   , the measurement light ML′ and the returned light RL′ may pass through a same area in the condensing optical system  3111 . However, at least a part of the optical path of the measurement light ML′ and at least a part of the optical path of the returned light RL′ may be optically separated from each other in the condensing optical system  3111 . 
     The returned light RL′ entering the condensing optical system  3111  is optically received (in other words, detected) by the light reception part  832   d  through the condensing optical system  3111  (namely, through the irradiation optical system  311 ). Thus, the light reception part  832   d  is configured to measure (in other words, observe or monitor) the workpiece W by detecting the returned light RL′. 
     A laser distance meter is one example of the measurement apparatus  83   d  including the light transmission part  831   d  and the light reception part  832   d . As the laser distance meter, a meter using a measurement method of a Time Of Flight method may be used as one example. In this case, the control apparatus  6  may calculate a distance between the measurement apparatus  83   d  and the workpiece W (especially, a distance between the measurement apparatus  83   d  and a position on the workpiece W that is irradiated with the measurement light ML′) based on a detected result of the returned light RL′ by the measurement apparatus  83   d . When the measurement apparatus  83   d  irradiates a plurality of positions on the workpiece W with the measurement light ML′, the control apparatus  6  may calculate distances between the measurement apparatus  83   d  and the plurality of positions on the workpiece W based on a detected result of the returned light RL′ by the measurement apparatus  83   d . As a result, the control apparatus  6  may calculate at least one of a position and a shape of the workpiece W based on the distances between the measurement apparatus  83   d  and the plurality of positions on the workpiece W. In this case, the control apparatus  6  may control the processing system SYSd so as to process the workpiece W based on at least one of the position and the shape of the workpiece W. Note that a meter using a measurement method of an interference method may be used as the laser distance meter. 
     The above described processing system SYSd in the fourth example embodiment is capable of achieving an effect that is same as the effect achievable by the above described processing system SYSb in the second example embodiment. Furthermore, the processing system SYSd is capable of processing the workpiece W based on the measured result of the workpiece W by the measurement apparatus  83   d  in addition to the measured result of the workpiece W by the measurement apparatus  83   d . Thus, the processing system SYSd is capable of properly processing the workpiece W. 
     Note that at least one of the processing system SYSa in the first example embodiment and the processing system SYSc in the third example embodiment may include a feature unique to the processing system SYSd in the fourth example embodiment. The feature unique to the processing system SYSd in the fourth example embodiment is feature related to the measurement apparatus  83   d.    
     (5) Processing System SYS in Fifth Example Embodiment 
     Next, with reference to  FIG.  28   , the processing system SYS in a fifth example embodiment (hereinafter, the processing system SYS in the fifth example embodiment is referred to as a “processing system SYSe”) will be described.  FIG.  28    is a system configuration diagram that illustrates a system configuration of the processing system SYS e in the fifth example embodiment. 
     As illustrated in  FIG.  28   , the processing system SYSe in the fifth example embodiment is different from the above described processing system SYSa in the first example embodiment in that it includes a collection apparatus  91   e  and a gas supply apparatus  92   e . Another feature of the processing system SYSe may be same as another feature of the processing system SYSa. Next, with reference to  FIG.  29   , operations of the collection apparatus  91   e  and the gas supply apparatus  92   e  will be described.  FIG.  29    is a planar view that conceptionally illustrates the operations of the collection apparatus  91   e  and the gas supply apparatus  92   e.    
     The collection apparatus  91   e  is configured to collect unnecessary substance generated by the irradiation with the processing lights EL from the chamber space  73 IN. Specifically, the collection apparatus  91   e  collects the unnecessary substance through a collection port  911   e  disposed in the chamber space  73 IN. The collection port  911   e  is directed toward the build surface MS that is irradiated with the processing lights EL. Especially, there is a high possibility that the unnecessary substance is generated from a position that is irradiated with the processing lights EL (namely, a position at which the melt pool MP is formed). Thus, the collection port  911   e  may be directed toward the position at which the melt pool MP is formed. 
     When the processing lights EL are shielded by the collection port  911   e , there is a possibility that the processing of the workpiece W by using the processing lights EL is affected. Thus, the collection port  911   e  may be disposed at a position that is away from the optical paths of the processing lights EL along a direction that intersects with the propagating directions of the processing lights EL (namely, a direction that intersects with the optical axis AX of the condensing optical system  3111 , and typically a direction along the XY plane). Namely, the collection port  911   e  may be disposed at a position that is away from the melt pool MP, which is irradiated with the processing lights EL, along the direction that intersects with the propagating directions of the processing lights EL. 
     The collection apparatus  91   e  collects the unnecessary substance together with a gas in the chamber space  73 IN by sucking the gas in the chamber space  73 IN (namely, exhausting the gas in the chamber space  73 IN) through the collection port  911   e . Thus, typically, a flow of the gas from the melt pool MP to the collection port  911   e  is formed. The unnecessary substance i s moved to the collection port  911   e  from the melt pool MP that is a main source of the unnecessary substance. As a result, the unnecessary substance is collected through the collection port  911   e . Here, when the flow of the gas (namely, a collection route of the unnecessary substance) from the melt pool MP to the collection port  911   e  exists on the optical paths of the processing lights EL, there is a possibility that the irradiation of the workpiece W with the processing lights EL is prevented by the unnecessary substance. Thus, the collection port  911   e  may collect the unnecessary substance so that the flow of the gas (namely, the collection route of the unnecessary substance) flowing from the melt pool MP to the collection port  911   e  does not exist on the optical paths of the processing lights EL. For example, as illustrated in  FIG.  29   , the collection port  911   e  may be disposed at a position that satisfies such a condition that a position that is away from a straight line including a line LN 1  connecting the melt pool MP and the collection port  911   e  (namely, a straight line along the flow of the gas formed by the collection port  911   e , and a straight line extending along the collection route of the unnecessary substance) toward a direction intersecting with both of this straight line and the optical paths of the processing lights EL (namely, the optical axis AX of the condensing optical system  3111 ) is irradiated with the processing lights EL. Conversely, the condensing optical system  3111  may irradiate the build surface MS with the processing lights EL so that the flow of the gas flowing from the melt pool MP to the collection port  911   e  does not exist on the optical paths of the processing lights EL. For example, as illustrated in  FIG.  29   , the condensing optical system  3111  may irradiate the position that is away from the straight line including the line LN 1  connecting the melt pool MP and the collection port  911   e  toward the direction intersecting with both of this straight line and the optical path of the processing light EL with the processing lights EL. 
     The gas supply apparatus  92   e  is configured to form a flow of the gas for removing the unnecessary substance generated by the irradiation with the processing lights EL from the build surface MS or a space facing the build surface MS by supplying the gas to the chamber space  73 IN. Specifically, the gas supply apparatus  92   e  supplies the gas to the chamber space  73 IN through a gas supply port  921   e  disposed in the chamber space  73 IN. The gas supply port  921   e  is directed toward the build surface MS that is irradiated with the processing lights EL. Especially, the gas supply port  921   e  may be directed toward the position at which the melt pool MP that is the main source of the unnecessary substance is formed. 
     When the processing lights EL are shielded by the gas supply port  921   e , there is a possibility that the processing of the workpiece W by using the processing lights EL is affected. Thus, the gas supply port  921   e  may be disposed at a position that is away from the optical paths of the processing lights EL along a direction that intersects with the propagating directions of the processing lights EL (namely, a direction that intersects with the optical axis AX of the condensing optical system  3111 , and typically a direction along the XY plane). Namely, the gas supply port  921   e  may be disposed at a position that is away from the melt pool MP, which is irradiated with the processing lights EL, along the direction that intersects with the propagating directions of the processing lights EL. 
     The gas supply apparatus  92   e  forms the flow of the gas from the gas supply port  921   e  by supplying the gas to the chamber space  73 IN from the gas supply port  921   e . The unnecessary substance is removed from the build surface MS or the space facing the build surface MS by the flow of the gas. Here, when the flow of the gas (namely, a removal route of the unnecessary substance) from the gas supply port  921   e  exists on the optical paths of the processing lights EL, there is a possibility that the irradiation of the workpiece W with the processing lights EL is prevented by the unnecessary substance. Thus, the gas supply port  921   e  may supply the gas so that the flow of the gas (namely, the removal route of the unnecessary substance) from the gas supply port  921   e  does not exist on the optical paths of the processing lights EL. For example, as illustrated in  FIG.  29   , the gas supply port  921   e  may be disposed at a position that satisfies such a condition that a position that is away from a straight line including a line LN 2  connecting the melt pool MP and the gas supply port  921   e  (namely, a straight line along the flow of the gas formed by the gas supply port  921   e , and a straight line extending along the removal route of the unnecessary substance) toward a direction intersecting with both of this straight line and the optical paths of the processing lights EL (namely, the optical axis AX of the condensing optical system  3111 ) is irradiated with the processing lights EL. Conversely, the condensing optical system  3111  may irradiate the build surface MS with the processing lights EL so that the flow of the gas (namely, the removal route of the unnecessary substance) from the gas supply port  921   e  does not exist on the optical paths of the processing lights EL. For example, as illustrated in  FIG.  29   , the condensing optical system  3111  may irradiate the position that is away from the straight line including the line LN 2  connecting the melt pool MP and the gas supply port  921   e  toward the direction intersecting with both of this straight line and the optical path of the processing light EL with the processing lights EL. 
     The unnecessary substance removed by the gas supplied from the gas supply apparatus  92   e  may be collected by the collection apparatus  91   e . In this case, in order to improve an efficiency for removing the unnecessary substance by the gas supply apparatus  92   e  and an efficiency for collecting the unnecessary substance by the collection apparatus  91   e , the gas supply port  921   e  and the collection port  911   e  may be disposed so that the melt pool MP that is the main source of the unnecessary substance is located between the gas supply port  921   e  and the collection port  911   e . In this case, a flow of the gas that flows from the gas supply port  921  to the collection port  911   e  through the melt pool MP that is the source of the unnecessary substance is formed, and thus, the unnecessary substance is efficiently removed and collected. 
     The above described processing system SYSe in the fifth example embodiment is capable of achieving an effect that is same as the effect achievable by the above described processing system SYSa in the first example embodiment. Furthermore, the processing system SYSe is capable of properly removing and/or collecting the unnecessary substance generated by the irradiation with the processing lights EL. Thus, the processing system SYSe is capable of properly reducing an influence caused by the unnecessary substance preventing the irradiation of the workpiece W with the processing lights EL. Thus, the processing system SYSe is capable of properly processing the workpiece W. 
     Note that the processing system SYSe includes both of the collection apparatus  91   e  and the gas supply apparatus  92   e  in the above described description. However, the processing system SYSe may include the collection apparatus  91   e  and may not include the gas supply apparatus  92   e . The processing system SYSe may include the gas supply apparatus  92   e  and may not include the collection apparatus  91   e.    
     Moreover, in the above described description, the processing system SYSe removes the unnecessary substance by using the gas supplied from the gas supply apparatus  92   e . However, the processing system SYSe may remove the unnecessary substance by using the gas (namely, the purge gas) supplied from the gas supply source  5 . Namely, the processing system SYSe may remove the unnecessary substance by supplying the purge gas to the chamber space  73 IN through the gas supply port  921   e . In this case, the processing system SYSe may not include the gas supply apparatus  92   e.    
     Moreover, at least one of the processing system SYSb in the second example embodiment to the processing system SYSd in the fourth example embodiment may include a feature unique to the processing system SYSe in the fifth example embodiment. The feature unique to the processing system SYSe in the fifth example embodiment is feature related to at least one of the collection apparatus  91   e  and the gas supply apparatus  92   e.    
     (6) Processing System SYS in Sixth Example Embodiment 
     Next, with reference to  FIG.  30   , the processing system SYS in a sixth example embodiment (hereinafter, the processing system SYS in the sixth example embodiment is referred to as a “processing system SYSf”) will be described.  FIG.  30    is a system configuration diagram that illustrates a system configuration of the processing system SYSf in the sixth example embodiment. 
     As illustrated in  FIG.  30   , the processing system SYSf in the sixth example embodiment is different from the above described processing system SYSa in the first example embodiment in that it includes a processing apparatus  3   f  instead of the processing apparatus  3 . Moreover, the processing system SYSf is different from the processing system SYSa in that it includes a gas supply apparatus  93   f . Another feature of the processing system SYSf may be same as another feature of the processing system SYSa. The processing apparatus  3   f  is different from the processing apparatus  3  in that it includes a processing head  31 f instead of the processing head  31 . Another feature of the processing apparatus  3   f  may be same as another feature of the processing apparatus  3 . The processing head  31 f is different from the processing head  31  in that it includes surrounding member  313   f . Another feature of the processing head  31 f may be same as another feature of the processing head  31 . Thus, next, with reference to  FIG.  31   , the surrounding member  313   f  will be described.  FIG.  31    is a cross-sectional view that illustrates a configuration of the surrounding member  313   f  in the sixth example embodiment. 
     As illustrated in  FIG.  31   , the surrounding member  313   f  is attached to a tip (specifically, a tip at the −Z side facing toward the workpiece W) of the irradiation optical system  311 . Namely, the surrounding member  313   f  is attached to a tip of the condensing optical system  3111 . 
     The surrounding member  313   f  surrounds at least a part of the material nozzle  312 . Namely, the surrounding member  313   f  surrounds at least a part of the supply path of the build materials M of the material nozzle  312 . Specifically, the surrounding member  313   f  surrounds at least a part of the material nozzle  312  that protrudes downwardly from the irradiation optical system  311 . Thus, a through-hole  3131 f into which a part of the material nozzle  312  is inserter is formed in the surrounding member  313   f . Furthermore, a through-hole  3132   f  for forming a space through which the processing lights EL emitted from the condensing optical system  3111  pass is formed in the surrounding member  313   f . Thus, the surrounding member  313   f  may include an inner wall member  3133   f  that surrounds the material nozzle  312  to form the through-hole  3131   f  and an outer wall member  3134 f that forms the through-hole  3132   f  with the inner wall member  3133   f  (namely, surrounds the inner wall member  3133   f  to form the through-hole  3132   f ). Namely, the surrounding member  313   f  may have a structure like a double pipe in which a pipe in which the material nozzle  312  is disposed and a pipe through which the processing lights EL pass are formed. In this case, the condensing optical system  3111 f irradiates the workpiece W with the processing lights EL through a space between the outer wall member  3134 f and the inner wall member  3133   f  (namely, a space between the outer wall member  3134 f and the material nozzle  312 ). Note that each of the inner wall member  3133   f  and the outer wall member  3134 f may be referred to as a wall member. 
     The through-hole  3132   f  is connected to the aperture  3113  (especially, the aperture  3113  of the terminal optical member  3114  of the condensing optical system  3111 ). Here, as described above, the purge gas supplied from the gas supply source  5  to the chamber space  73 IN is supplied to the space at the emitting plane side of the terminal optical member  3114  (typically, the workpiece W) through the apertures  3113 . Thus, when the through-hole  3132   f  is connected to the aperture  3113 , the purge gas supplied from the gas supply source  5  to the chamber space  73 IN is supplied to a space below the surrounding member  313   f  (namely, a space between the surrounding member  313   f  and the workpiece W) through the aperture  3113  and the through-hole  3132   f . Specifically, the purge gas is supplied to the through-hole  3132   f  corresponding to a space between the surrounding member  313   f  and the material nozzle  312  (specifically, a space between the outer wall member  3134 f and the material nozzle  312 ) through the aperture  3113  of the terminal optical member  3114 . The purge gas supplied to the through-hole  3132   f  is supplied to the space below the surrounding member  313   f  through an outlet port  3135   df  corresponding to a lower end of the through-hole  3132   f . Namely, the purge gas supplied to the through-hole  3132   f  is supplied to the workpiece W located below the surrounding member  313   f  from the outlet port  3135   f . In this case, the surrounding member  3131   fd  may serve as a gas guide member that guides the purge gas from the aperture  3113  of the terminal optical member  3114  to the workpiece W. 
     Even in this case, there is a high possibility that the build materials M from the supply outlet  314  is supplied along the supply path that is directed downwardly from the material nozzle  312  due to the flow of the gas supplied through the through-hole  3132   f , as described in the first example embodiment. Namely, there is a low possibility that the build materials M from the supply outlet  314  are scattered toward all directions from the material nozzle  312 . As a result, the material nozzle  312  is capable of properly supplying the build materials M. This effect is more pronounced when the outlet port  3135 f is formed near the supply outlet  314 . 
     Furthermore, the flow of the purge gas flowing from an inside of the through-hole  3132   f  to an outside of the through-hole  3132   f  is formed in the through-hole  3132   f  through which the processing lights EL pass. Thus, there is a low possibility that the unnecessary substance generated by irradiating the workpiece W with the processing lights EL enters the inside of the through-hole  3132   f . Thus, the influence caused by the unnecessary substance preventing the irradiation of the workpiece W with the processing lights EL is reduced. 
     The above described processing system SYSf in the sixth example embodiment is capable of achieving an effect that is same as the effect achievable by the above described processing system SYSa in the first example embodiment. Furthermore, the processing system SYSf is capable of properly supplying the build materials M along the supply path directed downwardly from the material nozzle  312  by using the purge gas supplied through the surrounding member  313   f , as described above. Namely, the processing system SYSf is capable of improving the directional characteristic of the supply direction of the build materials M. Furthermore, the processing system SYSf is capable of reducing the influence caused by the unnecessary substance preventing the irradiation of the workpiece W with the processing lights EL by using the purge gas supplied through the surrounding member  313   f.    
     Moreover, at least one of the processing system SYSb in the second example embodiment to the processing system SYSe in the fifth example embodiment may include a feature unique to the processing system SYSf in the sixth example embodiment. The feature unique to the processing system SYSf in the sixth example embodiment is feature related to the surrounding member  313   f.    
     (7) Processing System SYS in Seventh Example Embodiment 
     Next, the processing system SYS in a seventh example embodiment (hereinafter, the processing system SYS in the seventh example embodiment is referred to as a “processing system SYSg”) will be described. The processing system SYSg in the seventh example embodiment is different from the above described processing system SYSa in the first example embodiment in that it may perform a removal processing for removing a part of the workpiece W by irradiating the workpiece W with the processing lights EL. For example, the processing system SYSg may perform the removal processing so that a shape of the workpiece W is a desired shape. For example, the processing system SYSg may perform the removal processing to form a desired structure on the workpiece W. For example, the processing system SYSg may perform the removal processing to form a desired structure on the surface of the workpiece W. For example, the processing system SYSg may perform the removal processing so that the surface of the workpiece W is smoothed. 
     When the removal processing is performed, the processing system SYSg may form a riblet structure on the workpiece W. The riblet structure may be a structure by which a resistance (especially, at least one of a frictional resistance and a turbulent frictional resistance) of the surface of the workpiece W to a fluid is reducible. The riblet structure may include a structure by which a noise, which is generated when the fluid and the surface of the workpiece W relatively move, is reducible. The riblet structure may include a structure in which a plurality of grooves each of which extends along a first direction (for example, the Y axis direction) that is along the surface of the workpiece W are arranged along a second direction (for example, the X axis direction) that is along the surface of the workpiece W and that intersects with the first direction, for example. 
     When the removal processing is performed, the processing system SYSg may form any structure having any shape on the surface of the workpiece W. A structure that generates a swirl relative to a flow of the fluid on the surface of the workpiece W is one example of any structure. A structure for giving a hydrophobic property to the workpiece W is one example of any structure. A fine texture structure (typically, a concave and convex structure) that is formed regularly or irregularly in a micro/nano-meter order is another example of any structure. This fine texture structure may include at least one of a shark skin structure and a dimple structure that has a function of reducing a resistance from a fluid (a liquid and/or a gas). The fine texture structure may include a lotus leaf surface structure that has at least one of a liquid repellent function and a self-cleaning function (for example, has a lotus effect). The fine texture structure may include at least one of a fine protrusion structure that has a liquid transporting function (US2017/0044002A1), a concave and convex structure that has a lyophile effect, a concave and convex structure that has an antifouling effect, a moth eye structure that has at least one of a reflectance reduction function and a liquid repellent function, a concave and convex structure that intensifies only light of a specific wavelength by interference to have a structural color, a pillar array structure that has an adhesion function using van der Waals force, a concave and convex structure that has an aerodynamic noise reduction function, a honeycomb structure that has a droplet collection function, a concave and convex structure that improve an adhesion to a layer formed on the surface and so on. 
       FIG.  32    and  FIG.  33    illustrates the processing system SYSb.  FIG.  32    is a block diagram that illustrates a system configuration of the processing system SYSg.  FIG.  33    is a cross-sectional view that illustrates a configuration of the processing system SYSg. As illustrated in  FIG.  32    and  FIG.  33   , the processing system SYSg is different from the processing system SYSa in that it may not include the material supply source  1  and the mix apparatus  12 . Furthermore, the processing system SYSg is different from the processing system SYSa in that it may not includes the material nozzle  312 . Specifically, the processing system SYSg is different from the processing system SYSa in that it includes a processing apparatus  3   g  including a processing head  31   g  that does not include the material nozzle  312  instead of the processing apparatus  3  including the processing head  31  that includes the material nozzle  312 . Namely, the processing system SYSg is different from the processing system SYSa in that it may not include a component for supplying the build materials M. Another feature of the processing system SYSg may be same as another feature of the processing system SYSa. 
     The above described processing system SYSg may also perform the light characteristic control operation in at least a part of a period during which the removal processing operation is performed, as with the processing system SYSa. As a result, the processing system SYSg is capable of achieving an effect that is same as the effect achievable by the above described processing system SYSa. 
     Incidentally, when the removal processing is performed, the processing system SYSg may irradiate the workpiece W with the processing light EL including a plurality of pulsed lights. For example, the processing system SYSg may irradiate the workpiece W with the processing light EL including the plurality of pulsed lights the ON time of which is equal to or shorter than nano-seconds. 
     (8) Other Modified Example 
     In the above described description, the processing system SYS irradiates the workpiece W with the plurality of processing lights EL emitted from the plurality of processing light sources  2 , respectively. Namely, the processing system SYS includes the plurality of processing light sources  2 . However, the processing system SYS may divide a single light emitted from a single processing light source  2  into the plurality of processing lights EL and irradiate the workpiece W with the plurality of divided processing lights EL. Namely, the processing system SYS may include the single processing light source  2 . Here, each of the intensities of the plurality of divided processing lights EL may be changeable independently. Changing the intensity may include changing the intensity to be zero. In this case, a shutter may be disposed in each of the optical paths of the plurality of divided processing lights EL. Moreover, a light intensity adjustment member for actively changing the transmitted light intensity may be disposed in each of the optical paths of the plurality of divided processing lights EL in addition to or instead of disposing the shutter. 
     In the above described description, the processing system SYS processes the workpiece W by irradiating the workpiece W with the processing lights EL. However, the processing system SYS may process the workpiece W by irradiating the workpiece W with any energy beam. In this case, the processing system SYS may include a beam source that is configured to generate any energy beam and a beam irradiation apparatus that is configured to irradiate the workpiece W with any energy beam in addition to or instead of the processing light source  2  and the irradiation optical system  311 . At least one of a charged particle beam, an electromagnetic wave and the like is one example of any energy beam. A least one of an electron beam, an ion beam and the like is one example of the charged particle beam. 
     When the workpiece W is processed by any energy beam, the control apparatus  6  may control a characteristic of the energy beam by performing the above described light characteristic control operation. The characteristic of the energy beam may include an energy amount of the energy beam, for example. When the charged particle beam is used as the energy beam, the characteristic of the energy beam (namely, the characteristic of the charged particle beam) may include an electrical current density distribution of the charged particle beam (for example, an electrical current density distribution in a plane (typically, the build surface MS) intersecting with the propagating direction of the processing light EL), for example. 
     (9) Supplementary Note 
     With respect to the example embodiments described above, the following Supplementary Notes will be further disclosed. 
     [Supplementary Note 1] 
     A processing system that is configured to process an object, wherein 
     the processing system includes: 
     an irradiation optical system that is configured to irradiate the object with a plurality of energy beams; and 
     a beam characteristic change apparatus that is configured to change characteristics of the plurality of energy beams individually. 
     [Supplementary Note 1] 
     A processing system that is configured to process an object, wherein 
     the processing system includes: 
     an irradiation optical system that is configured to form a melt pool on the object by irradiating the object with a plurality of energy beams; and 
     a beam characteristic change apparatus that is configured change a temperature distribution of the melt pool by changing characteristics of the plurality of energy beams individually. 
     [Supplementary Note 3] 
     The processing system according to the Supplementary Note 1 including a detection apparatus that is configured to detect a light from the melt pool, 
     the beam characteristic change apparatus being configured to change a distribution of the energy beam based on a detected result by the detection apparatus. 
     [Supplementary Note 4] 
     A processing system that is configured to process an object, wherein 
     the processing system includes: 
     an irradiation optical system that is configured to irradiate the object with a plurality of energy beams; 
     a movement apparatus that is configured to move at least one of the object and irradiation positions of the energy beams; and 
     a beam characteristic change apparatus that is configured to change characteristics of the plurality of energy beams individually based on a moving direction by the movement apparatus. 
     [Supplementary Note 5] 
     The processing system according to any one of the Supplementary Notes 1 to 4, wherein 
     the characteristic of the energy beam includes an intensity of the energy beam. 
     [Supplementary Note 6] 
     A processing system that is configured to process an object, wherein 
     the processing system includes: 
     an irradiation optical system that is configured to form a melt pool on the object by irradiating the object with a plurality of energy beams from direction that are different from each other; and 
     a material supply apparatus that is configured to supply a material to the melt pool. 
     [Supplementary Note 7] 
     The processing system according to the Supplementary Note 6, wherein 
     a direction along which the material is supplied from the material supply apparatus to the melt pool is different from irradiation directions of the plurality of energy beams. 
     [Supplementary Note 8] 
     The processing system according to the Supplementary Note 6 or 7, wherein 
     the material supply apparatus is configured to supply the material from a material supply direction intersecting with a surface of the object. 
     [Supplementary Note 9] 
     A processing system that is configured to process an object by using an energy beam, wherein 
     the processing system includes: 
     an irradiation optical system that is configured to condense the energy beam to irradiate the object with it; 
     a material supply apparatus that is configured to supply a material to an irradiation position of the energy beam on the object; 
     a surrounding member that surrounds at least a part of a supply path of the material by the material supply apparatus; and 
     a gas supply apparatus that is configured to supply a gas to a space between a plurality of optical members included in the irradiation optical system, 
     the irradiation optical system emits the energy beam through a space between the surrounding member and at least a part of the material supply apparatus, 
     the gas from the gas supply apparatus is supplied to the space between the surrounding member and at least a part of the material supply apparatus. 
     [Supplementary Note 10] 
     The processing system according to the Supplementary Note 9, wherein 
     the gas from the gas supply apparatus is supplied to through an aperture formed at least partial optical member of the optical members included in the irradiation optical system. 
     [Supplementary Note 11] 
     The processing system according to the Supplementary Note 9 or 10, wherein 
     the at least a part of the material supply apparatus is disposed along an optical axis of the irradiation optical system. 
     [Supplementary Note 12] 
     A processing system that is configured to process an object by using an energy beam, wherein 
     the processing system comprises: 
     an irradiation optical system that is configured to irradiate the object with the energy beam; and 
     a detection apparatus that is configured to detect, through the irradiation optical system, an object light including a light from the object, 
     at least a part of a path of the object light in the irradiation optical system is different from at least a part of a path of the energy beam in the irradiation optical system. 
     [Supplementary Note 13] 
     The processing system according to the Supplementary Note 12, wherein 
     the object light is a first object light, 
     the detection apparatus is a first detection apparatus, 
     the processing system further includes a second detection apparatus that is configured to detect, through the irradiation optical system, a second object light that includes a light from the object and that is different from the first object light. 
     [Supplementary Note 14] 
     The processing system according to the Supplementary Note 13, wherein 
     at least a part of a path of the second object light in the irradiation optical system is different from each of at least a part of the path of the energy beam in the irradiation optical system and at least a part of a path of the first object light in the irradiation optical system. 
     [Supplementary Note 15] 
     The processing system according to any one of the Supplementary Notes 12 to 14 further including an irradiation apparatus that is configured to irradiate the object with a measurement light through the irradiation optical system. 
     [Supplementary Note 16] 
     The processing system according to the Supplementary Note 15, wherein at least a part of a path of the measurement light in the irradiation optical system is different from at least a part of the path of the energy beam in the irradiation optical system. 
     [Supplementary Note 17] 
     The processing system according to the Supplementary Note 15 or 16, wherein 
     the object light includes a light from the object that is irradiated with the measurement light. 
     [Supplementary Note 18] 
     The processing system according to any one of the Supplementary Notes 15 to 17, wherein 
     the object light includes at least one of a reflected light, a scattered light and a transmitted light of the measurement light from the object. 
     [Supplementary Note 19] 
     The processing system according to any one of the Supplementary Notes 15 to 18 further including a position change apparatus that is configured to change an irradiation position of the energy beam on the object. 
     [Supplementary Note 20] 
     The processing system according to the Supplementary Note 19, wherein 
     the position change apparatus is configured to change an irradiation position of the measurement light so that at least one of a first position that has been irradiated with the energy beam on the object, a second position that is being irradiated with the energy beam on the object and a third position that is expected irradiated with the energy beam on the object is irradiated with the measurement light. 
     [Supplementary Note 21] 
     The processing system according to the Supplementary Note  20  further including a light guide optical system that is configured to guide the object light from the first position to the detection apparatus in at least a part of a period during which the first position is irradiated with the measurement light, to guide the object light from the second position to the detection apparatus in at least a part of a period during which the second position is irradiated with the measurement light, and to guide the object light from the third position to the detection apparatus in at least a part of a period during which the third position is irradiated with the measurement light. 
     [Supplementary Note 22] 
     The processing system according to any one of the Supplementary Notes 15 to 21, wherein 
     the measurement light is a first measurement light, 
     the irradiation apparatus is a first irradiation apparatus, 
     the processing system further includes a second irradiation apparatus that is configured to irradiate the object with a second measurement light that is different from the first measurement light through the irradiation optical system. 
     [Supplementary Note 23] 
     The processing system according to the Supplementary Note 22, wherein 
     at least a part of a path of the second measurement light in the irradiation optical system is different from each of at least a part of the path of the energy beam in the irradiation optical system and at least a part of a path of the first measurement light in the irradiation optical system. 
     [Supplementary Note 24] 
     The processing system according to the Supplementary Note 22 or 23, wherein the object light is a first object light, 
     the detection apparatus is a first detection apparatus, 
     the processing system further includes a second detection apparatus that is configured to detect, through the irradiation optical system, a second object light that includes a light from the object and that is different from the first object light, 
     the first object light includes a light from the object that is irradiated with the first measurement light, 
     the second object light includes a light from the object that is irradiated with the second measurement light. 
     [Supplementary Note 25] 
     The processing system according to the Supplementary Note 24, wherein 
     the first object light includes at least one of a reflected light, a scattered light and a transmitted light of the first measurement light from the object, 
     the second object light includes at least one of a reflected light, a scattered light and a transmitted light of the second measurement light from the object. 
     [Supplementary Note 26] 
     A processing system that is configured to process an object by using a plurality of energy beams, wherein 
     the processing system comprises: 
     a plurality of beam sources that are configured to emit the plurality of energy beams, respectively; 
     an irradiation optical system that is configured to irradiate the object with the plurality of energy beams from the plurality of beam sources; and 
     a control apparatus that is configured to change characteristics of the plurality of energy beams individually by controlling each of the plurality of beam sources. 
     [Supplementary Note 27] 
     The processing system according to the Supplementary Note 26, wherein 
     the control apparatus is configured to control each of the plurality of beam sources so that the characteristic of a first energy beam of the plurality of energy beams is different from the characteristic of a second energy beam of the plurality of energy beams that is different from the first energy beam. 
     [Supplementary Note 28] 
     The processing system according to the Supplementary Note 26 or 27 further including a movement apparatus that is configured to relatively move irradiation positions of the plurality of energy beams relative to the object, 
     the control apparatus is configured to control each of the plurality of beam sources based on a movement information related to a movement of the irradiation positions of the plurality of energy beams. 
     [Supplementary Note 29] 
     The processing system according to the Supplementary Note 28, wherein 
     the movement information includes an information related to a moving direction of the irradiation positions of the plurality of energy beams. 
     [Supplementary Note 30] 
     The processing system according to the Supplementary Note 29, wherein 
     the characteristic of the energy beam includes an intensity of the energy beam, 
     the control apparatus is configured to control each of the plurality of beam sources so that the intensity of a first energy beam of the plurality of energy beams is lower than the intensity of a second energy beam of the plurality of energy beams that is different from the first energy beam, 
     the irradiation position of the first energy beam on the object is located at a rear side along the moving direction from the irradiation position of the second energy beam on the object. 
     [Supplementary Note 31] 
     The processing system according to the Supplementary Note  30 , wherein 
     the control apparatus is configured to control each of the plurality of beam sources so that the intensity of the second energy beam is zero. 
     [Supplementary Note 32] 
     The processing system according to any one of the Supplementary Notes 29 to 31, wherein 
     the control apparatus is configured to control each of the plurality of beam sources so that a first energy beam of the plurality of energy beams is a pulsed beam and a second energy beam of the plurality of energy beams that is different from the first energy beam is a continuous beam, 
     the irradiation position of the first energy beam on the object is located at a rear side along the moving direction from the irradiation position of the second energy beam on the object. 
     [Supplementary Note 33] 
     The processing system according to any one of the Supplementary Notes 26 to 32, wherein 
     the control apparatus is configured to control each of the plurality of beam sources based on an object information related to the object. 
     [Supplementary Note 34] 
     The processing system according to the Supplementary Note 33, wherein 
     the object information includes an information related to a shape of the object. 
     [Supplementary Note 35] 
     The processing system according to the Supplementary Note 34, wherein
         the irradiation optical system is configured to irradiate a first part of the object with a third energy beam of the plurality of energy beams,   the control apparatus is configured to control each of the plurality of beam sources so that an intensity of a fourth energy beam of the plurality of energy beams is equal to or lower than a predetermined intensity, a second part of the object exists on a path of the fourth energy beam from the irradiation optical system to the first part.       

     [Supplementary Note 36] 
     The processing system according to the Supplementary Note 35, wherein
         the predetermined intensity is an intensity of the energy beam by which the object cannot be processed or zero.       

     [Supplementary Note 37] 
     The processing system according to any one of the Supplementary Notes  26  to  36 , wherein
         in a predetermined plane intersecting with an optical axis of the irradiation optical system, at least two of the plurality of energy beams pass through areas that are symmetric about the optical axis.       

     [Supplementary Note 38] 
     The processing system according to any one of the Supplementary Notes 26 to 37, wherein
         in a predetermined plane intersecting with an optical axis of the irradiation optical system, at least two of the plurality of energy beams pass through areas that are asymmetric about the optical axis.       

     [Supplementary Note 39] 
     The processing system according to any one of the Supplementary Notes 26 to 38, wherein
         the plurality of energy beams include a first energy beam, a second energy beam, a third energy beam and a fourth energy beam,   in a predetermined plane intersecting with an optical axis of the irradiation optical system, the first energy beam and the second energy beam pass through positions between which the optical axis exists along a first direction along the predetermined plane,   in the predetermined plane, the third energy beam and the fourth energy beam pass through positions between which the optical axis exists along a second direction that is along the predetermined plane and that intersects with the first direction.       

     [Supplementary Note 40] 
     The processing system according to any one of the Supplementary Notes 26 to 39, wherein
         the plurality of energy beams form a ring-shaped bean form in a predetermined plane intersecting with an optical axis of the irradiation optical system.       

     [Supplementary Note 41] 
     The processing system according to any one of the Supplementary Notes 26 to 40, wherein
         the processing system forms a melt pool on the object by irradiating the object with the plurality of energy beams,   the processing system further includes a gas supply apparatus that is configured to supply a gas to the melt pool through a supply port disposed at a position that is away from the melt pool,   a position that is away from a straight line, which include a line connecting the melt pool and the supply port, toward a direction intersecting with the straight line is irradiated with plurality of energy beams.       

     [Supplementary Note 42] 
     The processing system according to any one of the Supplementary Notes 26 to 41, wherein
         the processing system forms a melt pool on the object by irradiating the object with the plurality of energy beams,   the processing system further includes a collection apparatus that is configured to collect a substance generated by the irradiation with the plurality of energy beams through a collection port disposed at a position that is away from the melt pool,   a position that is away from a straight line, which include a line connecting the melt pool and the collection port, toward a direction intersecting with the straight line is irradiated with plurality of energy beams.       

     [Supplementary Note 43] 
     The processing system according to any one of the Supplementary Notes 26 to 42 further including a wall member that forms a space in which the energy beam from the irradiation optical system propagates. 
     [Supplementary Note 44] 
     The processing system according to any one of the Supplementary Notes 26 to 43 further including a gas supply apparatus that is configured to supply a gas to the space. 
     [Supplementary Note 45] 
     The processing system according to the Supplementary Note 45 further including a material supply apparatus that is configured to supply a material from a supply port,
         the gas supplied to the space flowing out from the space through a discharge port formed at the wall member near the supply port.       

     At least a part of the features of each embodiment described above may be properly combined with at least another a part of the features of each embodiment described above. A part of the features of each embodiment described above may not be used. Moreover, the disclosures of all publications and United States patents that are cited in each embodiment described above are incorporated in the disclosures of the present application by reference if it is legally permitted. 
     The present invention is not limited to the above described examples and is allowed to be changed, if desired, without departing from the essence or spirit of the invention which can be read from the claims and the entire specification. A processing system, which involves such changes, is also intended to be within the technical scope of the present invention. 
     DESCRIPTION OF REFERENCE CODES 
     
         
         SYS processing system 
           1  material supply apparatus 
           2  processing light source 
           3  processing apparatus 
           31  processing head 
           311  irradiation optical system 
           3111  condensing optical system 
           32  head driving system 
           4  stage apparatus 
           41  stage 
           42  stage driving system 
           6  control apparatus 
         W workpiece 
         M build material 
         SL structural layer 
         MS build surface 
         EL processing light