Abstract:
A laser safety enclosure structure has an outer enclosure made of a formable material with a limited ability to withstand exposure to a laser beam and an inner enclosure composed of a laser beam blocking material capable of indefinitely withstanding exposure to a laser beam of a given wavelength and power level so as to prevent such a laser beam incident on the blocking material from escaping the inner enclosure.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is a continuation-in-part of co-pending U.S. application Ser. No. 10/210,121, filed on Jul. 31, 2002; and of co-pending U.S. application Ser. No. 29/186,395, filed on Jul. 14, 2003, the disclosures of both applications being incorporated herein by reference in their respective entireties. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     This invention relates to laser material processing systems, and in particular to a laser enclosure for safely containing the laser light used in such laser material processing systems.  
         [0004]     2. Description of the Related Art  
         [0005]     Material processing systems using high power lasers must be housed in enclosures which contain the laser beam and prevent human exposure to laser radiation in excess of safe limits. This is not only good design practice, but is also required by both federal and state regulations as overseen by the Center for Devices and Radiological Health (CDRH), a division of the Food and Drug Administration (FDA). According to federal regulations, in particular, 21 C.F.R. § 1040.10(f)(1), entitled PERFORMANCE REQUIREMENTS—(1) PROTECTIVE HOUSING: “Each laser product shall have a protective housing that prevents human access during operation to laser and collateral radiation that exceed the limits of Class I and table VI, respectively, wherever and whenever such human access is not necessary for the product to perform its intended function.” 
         [0006]     To provide a Class I enclosure, the materials employed in the housing must be able to withstand indefinitely direct exposure to the beam of the laser in use in the system.  
         [0007]     Common practice is to use sheet metal as the housing material to meet these requirements. However, sheet metal has the following drawbacks: 
        1. sheet metal manufacturing methods may be relatively expensive, especially for mass production;     2. low volume sheet metal manufacturing methods do not allow a wide range of shapes for the enclosures, which limits options for design aesthetics; and     3. stamping methods for sheet metal allow a wider range of shapes, but require expensive up-front tooling costs and are usually reserved for high volume manufacturing.        
 
         [0011]     Plastics solve many of these problems, reducing material, tooling, and manufacturing costs and allowing a much wider range of shapes. However, plastics do not meet safety guidelines because they cannot contain a beam indefinitely in the case of direct exposure to the laser beam.  
         [0012]     An exception to the requirement of indefinite containment is the use of visibly transparent plastics as view ports, as long as the plastics are not permeable to the laser wavelength in use. This is allowable if the material is capable of preventing the laser beam from penetrating through for a reasonable period of time, and so to allow the operator to recognize a problem and to turn off the equipment while at the same time, by nature of its transparency to visible light, providing the operator with a visual cue that a problem is occurring.  
         [0013]     An example of this is the use of acrylic plastic as a view port for systems employing CO 2  lasers operating at 10.6 microns. The acrylic does not transmit this laser wavelength, but is transparent to visible light, allowing the operator to see whether the laser beam is striking the view port, or whether some other problem is occurring, before the beam burns through the view port, allowing the operator time to turn off the equipment before the enclosure is compromised.  
         [0014]     Accordingly, manufacturers of laser material processing systems have conventionally used sheet metal enclosures to contain the laser beam and have employed clear glass or plastic only as viewing ports. As a result, since such systems are not usually built in large quantities, their enclosures have generally been restricted to square, boxy shapes.  
       BRIEF SUMMARY OF THE INVENTION  
       [0015]     It is therefore an object of the present invention to provide a laser enclosure for a laser material processing system that avoids the above-described difficulties of the prior art.  
         [0016]     It is a further object of the present invention to provide a laser enclosure for a laser material processing system that provides the required degree of safety while at the same time is able to be manufactured in any desired shape at a reasonable cost.  
         [0017]     The above and other objects are achieved by the present invention which, in one embodiment, is directed to a laser safety enclosure structure with a composite structure, having an outer enclosure having an interior surface, with the outer enclosure being made of a formable material with a limited ability to withstand exposure to a laser beam, and an inner enclosure covering substantially all of the interior surface and defining an interior volume for containing a laser beam, with the inner enclosure being composed of at least one layer of a laser beam blocking material capable of indefinitely withstanding exposure to a laser beam of a given wavelength and power level so as to prevent such a laser beam incident on the laser blocking material from escaping the inner enclosure.  
         [0018]     In a preferred embodiment, the formable material is plastic and the laser blocking material is metal.  
         [0019]     In the present invention, the laser safety enclosure includes a rigid outer enclosure having an interior surface, the outer enclosure being made of a formable material that becomes rigid after forming with a limited ability to withstand exposure to a laser beam; and an inner laser containment structure covering substantially all of the interior surface and defining an interior volume for containing a laser beam, the inner laser containment structure being composed of at least one layer of a laser beam blocking material capable of indefinitely withstanding exposure to a laser beam of a given wavelength and power level, the laser beam blocking capability being sufficient to prevent such a laser beam incident on the laser beam blocking material from escaping the inner laser containment structure.  
         [0020]     The laser safety enclosure may have the inner laser containment structure including a first layer of laser beam blocking material connected to the interior surface. The first layer of laser beam blocking material may be laminated on the inner surface. The first layer of laser beam blocking material may also be connected to the interior surface using an adhesive. The first layer of laser beam blocking material may also be connected to the interior surface using at least one mechanical fastener.  
         [0021]     The inner laser containment structure may also include a second layer of a formable material that becomes rigid after forming with a limited ability to withstand exposure to a laser beam, the first layer being sandwiched between the second layer and the interior surface of the outer enclosure. The first layer of the at least one layer of laser beam blocking material may be metal. The layer of formable material may be a plastic.  
         [0022]     The present invention also includes a method of making a laser safety enclosure, comprising the steps of forming a rigid outer enclosure of a formable material that becomes rigid after forming with limited ability to withstand exposure to a laser beam, the outer enclosure having an interior surface; and making an inner laser containment structure of at least one layer of laser beam blocking material covering substantially all of the interior surface and defining an interior volume for containing a laser beam, the inner laser containment structure being composed of a material capable of withstanding indefinite exposure to a beam of a given wavelength and power level, the laser beam blocking capability being sufficient to prevent such a laser beam from escaping the inner laser containment structure.  
         [0023]     The outer enclosure and the inner containment structure are made by the steps of: providing a sheet of formable material that becomes rigid after forming which presents a first surface that will become the interior surface of the outer enclosure; applying a first layer of laser beam blocking material to the first surface to form a laminate; and drawing the laminate into a predetermined shape to constitute the outer enclosure and the inner containment structure.  
         [0024]     The applying step includes the step of attaching the laser beam blocking material to the first surface using an adhesive. In the method, the at least one layer of laser beam blocking material includes metal. Also in the method, the layer of formable material includes plastic. At least one of the step of forming the inner laser containment structure and the step of forming the outer enclosure employs a technique selected from the group of vacuum forming techniques, injection molding techniques, casting techniques and stamping techniques.  
         [0025]     The step of forming the outer enclosure initially forms the outer enclosure as a separate entity, and the step of making the inner laser containment structure includes the step of attaching the laser beam blocking material to the interior surface of the formed outer enclosure to form the inner laser containment structure.  
         [0026]     The step of making the outer enclosure initially forms the inner laser containment structure as a separate entity, and the attaching step includes the step of connecting the made inner laser containment structure to the interior surface of the formed outer enclosure.  
         [0027]     In the method, the inner laser containment structure is made by stamping the laser beam blocking material. Also in the method, the attaching step includes the step of applying the laser beam blocking material to the interior surface as a powder. The powder may include a metal and is attached to the interior surface by an application technique selected from the group of spraying and sintering.  
         [0028]     The present invention also includes a laser safety enclosure, which includes a rigid laser containment structure made from a plurality of walls and defining an interior volume for containing a laser beam, each of the walls being formed from: a mixture of a moldable material; and a laser beam blocking material in an amount sufficient to make the walls capable of withstanding indefinite exposure to a laser beam of a given wavelength and power level, the laser beam blocking capability being sufficient to prevent such a laser beam from escaping the laser containment structure. In this laser safety enclosure, the moldable material may be a plastic resin. The laser beam blocking material may be a metal powder.  
         [0029]     The present invention also includes a method of making a laser safety enclosure, having the steps of: making a mixture of moldable material and an amount of laser beam blocking material sufficient to make a wall formed of the mixture capable of withstanding indefinite exposure to a laser beam of a given wavelength and power level, the laser beam blocking capability being sufficient to prevent such a laser beam from escaping through the wall; and making a laser containment structure having a wall formed of the mixture. In the method, the moldable material includes a plastic resin. Also in the method, the laser beam blocking material may be a metal powder.  
         [0030]     The present invention also includes a laser safety enclosure for containing a material object for laser processing thereof, and includes an outer containment structure having an interior surface, the outer containment structure being made of a formable material and including a base member having an upstanding wall which defines an enclosed space for supporting the material object thereon to be processed by a laser beam; and an inner containment structure covering substantially all of the interior surface and defining an interior volume for containment of the laser beam, the inner containment structure being composed of at least one layer of a laser beam blocking material capable of indefinitely withstanding exposure to a laser beam of a predetermined wavelength and power level, the laser beam blocking capability being sufficient to prevent the laser beam incident thereupon from escaping the inner containment structure.  
         [0031]     The present invention also includes a method of making a laser safety enclosure for containing a material object for laser processing thereof, with the steps of: forming an outer containment structure of a formable material and including a base member having an upstanding wall which defines an enclosed space for supporting the material object thereon to be processed by a laser beam, the outer containment structure having an interior surface; and making an inner containment structure of at least one layer of laser beam blocking material covering substantially all of the interior surface and defining an interior volume for containment of a laser beam, the inner containment structure being composed of a material capable of withstanding indefinite exposure to a laser beam of a predetermined wavelength and power level, the laser beam blocking capability material being sufficient to prevent the laser beam incident thereupon from escaping the inner containment structure.  
         [0032]     The present invention also includes a laser safety enclosure for containing a material object for laser processing thereof, having a containment structure made from a base member having an upstanding wall which defines an enclosed space for supporting the material object thereon to be processed by a laser beam, and defining an interior volume for containment of a laser beam, each of the base and upstanding wall being formed from a mixture of a moldable material and a laser beam blocking material in an amount sufficient to make the base and upstanding wall capable of withstanding indefinite exposure to a laser beam of a predetermined wavelength and power level, the laser beam blocking material capability being sufficient to prevent the laser beam incident thereupon from escaping the containment structure.  
         [0033]     The present invention also includes a method of making a laser safety enclosure for containing a material object for laser processing thereof, having the steps of: making a mixture of moldable material and an amount of laser beam blocking material sufficient to make a base member having an upstanding wall formed of the mixture capable of withstanding indefinite exposure to a laser beam of a predetermined wavelength and power level, the laser beam blocking capability being sufficient to prevent the laser beam incident thereupon from escaping through the base member or the upstanding wall; and making a containment structure having the base member including the upstanding wall formed of the mixture.  
         [0034]     The present invention also includes a laser safety enclosure structure with composite structure, having an outer enclosure having an interior surface, the outer enclosure being made of a formable material and including a base member having an upstanding wall which defines an enclosed space for supporting the material object thereon to be processed by a laser beam; and an inner enclosure covering substantially all of the interior surface and defining an interior volume for containing a laser beam, the inner enclosure being composed of at least one layer of a laser beam blocking material, including a first layer, capable of indefinitely withstanding exposure to a laser beam of a predetermined wavelength and power level, the laser beam blocking capability being sufficient to prevent the laser beam incident thereupon from escaping the inner enclosure; and wherein at least the first layer of laser beam blocking material is connected to the interior surface using at least one mechanical fastener.  
         [0035]     These and other objects, features, and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments taken in conjunction with the following drawings, wherein like reference numerals denote like elements. 
     
    
     BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS  
       [0036]     Preferred embodiments of the invention are disclosed hereinbelow with reference to the drawings, wherein:  
         [0037]      FIG. 1  is a top front left side perspective view of a laser cabinet incorporating a laser safety enclosure of the present invention;  
         [0038]      FIG. 2  is a side cross-sectional view of the laser safety enclosure along lines  2 - 2  in  FIG. 1  in accordance with a first preferred embodiment of the present invention;  
         [0039]      FIG. 3  is a side cross-sectional view of the laser safety enclosure along lines  2 - 2  in  FIG. 1  in accordance with a second preferred embodiment of the present invention;  
         [0040]      FIG. 4  is a side cross-sectional view of the laser safety enclosure along lines  2 - 2  in  FIG. 1  in accordance with a third preferred embodiment of the present invention;  
         [0041]      FIG. 5  is a side cross-sectional view of the laser safety enclosure along lines  2 - 2  in  FIG. 1  in accordance with a fourth preferred embodiment of the present invention;  
         [0042]      FIG. 6  is a side cross-sectional view of the laser safety enclosure along lines  2 - 2  in  FIG. 1  in accordance with a fifth preferred embodiment of the present invention;  
         [0043]      FIG. 7  is a side cross-sectional view of the laser safety enclosure along lines  2 - 2  in  FIG. 1  in accordance with a sixth preferred embodiment of the present invention; and  
         [0044]      FIG. 8  is a side cross-sectional view of an alternative embodiment of the laser safety enclosure in accordance with a seventh preferred embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0045]     The present invention is generally directed to a composite structure for a laser safety enclosure in which the exterior material of an outer enclosure is selected for low cost and ease of manufacturing and the ability to be formed into more complex, curved, homogeneous shapes with greater aesthetic appeal and without regard to the ability of the exterior material to block and contain the laser beam. As used in the present application, a material having this ability to be formed into such shapes is termed a formable material, a primary example being plastic.  
         [0046]     The use of this exterior material is combined with the use of an interior material to make an inner enclosure forming an inner laser containment structure having laser beam blocking capability, with the inner material being selected for its ability to block and contain the laser beam. A primary example of a suitable inner material is metal.  
         [0047]     As shown in  FIG. 1 , a laser cabinet  10  is illustrated in a top front left side perspective view, with the laser cabinet  10  incorporating a laser safety enclosure  12  of the present invention. The laser cabinet  10  includes an outer housing  14  in which is mounted the laser safety enclosure  12 . A control device  16  such as a plurality of operating buttons may extend through apertures in the outer housing  14 , and at least one vent may be provided for the exhaust of heat from the laser cabinet  10  during the laser operations. The laser cabinet  10  and the laser safety enclosure  12  are dimensioned to receive therein a workpiece  20  to be etched, engraved, and/or cut by a laser beam  22  from a laser device, for example, positioned behind the wall  28 . The laser beam  22  is directed from the laser device through an aperture  18  in, for example, the wall  28  to be incident upon optics, such as mirrors and/or lenses, mounted on and/or within the moveable arm  44  which direct the laser beam  22  to optics, such as mirrors and/or lenses including a focusing lens, on and/or within a moveable carriage  24  which finally direct the laser beam  22  downward onto the workpiece  20 . As described herein, the moveable arm  44  moves in any direction parallel to the Y-axis within the laser safety enclosure  12 , and the moveable carriage  24  moves along the movable arm  44  in any direction parallel to the X-axis within the laser safety enclosure to direct the laser beam  22  onto any location in the X-Y plane, such as any predetermined position on the workpiece  20  to be etched, engraved, and/or cut by the laser beam  22 .  
         [0048]     The laser safety enclosure  12  includes a plurality of upstanding walls and wall portions, such as the upstanding walls  26 ,  28 ,  30  extending upward from a base member  32 , with the upstanding walls  26 - 30  and the base member  32  being wall portions fabricated from materials described herein to be substantially rigid; that is, retaining a single firm and stiff configuration after initial fabrication. The upstanding walls  26 - 30  and base member  32  define an interior space  34  therein for receiving the workpiece  20  which is etched, engraved, or cut by the laser beam  22 .  
         [0049]     By having such upstanding walls  26 - 30  and the base member  32  capable of substantially and/or completely blocking any laser beams  22  or reflections therefrom originating within the laser safety enclosure  12  as the workpiece  20  is etched, engraved, or cut, any laser beams  22  which pass through the workpiece  20  or which otherwise do not contact the workpiece  20  are blocked by the upstanding walls  26 - 30  and the base member  32  and thus are prevented from exiting the laser safety enclosure  12  and the laser cabinet  10 . Therefore, both the control electronics of the laser cabinet  10  and the user of the laser cabinet  10  are protected from damage during the laser operations of the laser cabinet  10 .  
         [0050]     The interior space  34  of the laser safety enclosure  12  is accessible through an opening  36  in the outer housing  14 , which may be removably covered by a hinged or removable door  38 . The door  38  may include a frame  40  for retaining glass or other materials forming at least one window  42  which may be transparent or opaque. In a preferred embodiment, the frame  40  retains plastic panes which are opaque to the wavelength of the laser beam  22 , but which may be transparent to other wavelengths of light, such as visible light to allow the operator to monitor the laser operations. In additional embodiments, the walls  26 - 30  and the base member  32  as well as additional laser blocking walls and/or panels wrap around the top on the right and left of the at least one window  42 , such that the window  42  slightly overlaps the laser safety enclosure  12  so that unintentional reflections of the laser beam  22  inside the laser safety enclosure  12  cannot escape the enclosure  12 .  
         [0051]     Accordingly, by opening or removing the door  38 , a user may place the workpiece  20  on the base member  32  in any orientation in the interior space  34  for the workpiece  20  to be worked on by the laser beam  22 . The workpiece  20  may then be removed from the interior space  34  through the door  38  after the laser operations are completed.  
         [0052]     The moveable carriage  24  is mounted on a motion device, such as at least one movable arm  44 , for maneuvering the laser beam  22  in any selected direction in the X-Y plane, such as a programmed path of travel in order to selectively direct the laser beam  22  from the laser device behind the wall  28  to be incident at any desired target locations  46  on the workpiece  20 .  
         [0053]     The laser device, the moveable carriage  24 , the motion device with the at least one moveable arm  44 , and other components of the laser cabinet  10  are described in commonly assigned U.S. Pat. Nos. 5,661,746; 5,754,575; 5,867,517; 5,881,087; 5,894,493; 5,901,167; 5,982,803; 6,181,719;6,313,433; 6,342,687; 6,423,925; and 6,424,670, each of which is incorporated herein by reference in their respective entireties.  
         [0054]     The present invention is directed to the laser safety enclosure  12 , with various embodiments  48 - 58  shown in  FIGS. 2-7 , respectively. Generally, the laser safety enclosure  12 , in its various embodiments, includes an inner laser containment structure and an optional outer structure in which the inner laser containment structure is placed. The inner laser containment structure includes a laser beam blocking material such as metal or other known substances having laser beam blocking capacity; that is, the inner laser containment structure is capable of blocking laser beams from passing therethrough.  
         [0055]      FIG. 2  is a side cross-sectional view of a first embodiment of the present invention, with at least one rigid wall portion  60  shaped to form the laser safety enclosure  48  with the upstanding walls  26 ,  30  and the base member  32  of the laser safety enclosure  48 , with the cross-sectional view taken along lines  2 - 2  in  FIG. 1  in accordance with the present invention. It will be understood that substantially all of the wall portions forming the upstanding walls  26 - 30  and the base member  32  of the laser safety enclosure  48  have the disclosed composite structure of the wall portion  60 , with the possible exception of a viewing port or window  42  constructed in accordance with conventional techniques.  
         [0056]     As shown in  FIG. 2 , the wall portion  60  includes a first layer  62  of a suitable exterior material as defined above and forming an outer enclosure. The wall portion  60  also includes a second layer  64  of a suitable interior material as defined above and forming an inner laser containment structure. In accordance with a preferred embodiment of the present invention, the first layer  62  is plastic and the second layer  64  is metal, for example, aluminum. The wall portion  60 , and the rest of the laser safety enclosure  48 , including of the first layer  62  and the second layer  64 , are created, for example, by applying a thin foil of aluminum to the inside of a sheet of plastic material using adhesive and then drawing the plastic and foil laminate into the appropriate shape using any suitable technique, for example, by vacuum forming techniques.  
         [0057]     The foil must be of an appropriate thickness both to provide sufficient mechanical strength against tearing during the forming process and over the life of the enclosure  48 , and to contain indefinitely the laser beam  22  of the intended wavelength and power level in order to meet the safety requirements. Experimental trials have indicated that the ranges of about 0.010 inches (0.0254 cm.) to about 0.015 inches (0.0381 cm.) thick for aluminum and about 0.005 inches (0.0127 cm.) to about 0.010 inches (0.0254 cm.) thick for copper meet both goals for unfocused CO 2  laser beams with power levels under about 150 watts. It will be understood that an appropriate thickness of a suitable interior material appropriate for any specified laser wavelength and power level may be determined by one of ordinary skill in the art in accordance with the teachings of this specification.  
         [0058]     Referring again to  FIG. 1 , when a viewing port or window  42  is provided for viewing the interior space  34  or volume from the outside of any of the various embodiments of the laser safety enclosure described herein, the laser blocking material is absent from the window  42 .  
         [0059]     Other methods of constructing the wall portion  60  of the laser safety enclosure  48  in  FIG. 2  are contemplated to be within the scope of the present invention. For example, in the embodiment of the laser safety enclosure  50  shown in  FIG. 3 , a third layer  66  of plastic may be used, with the second layer  64  of metal between the first layer  62  and the third layer  66 . In this embodiment, the first layer  62  is the outer enclosure, and the combination of the second layer  64  and the third layer  66  is the inner laser containment structure.  
         [0060]     To create this structure, the foil may be laminated between two sheets of plastic and then formed into the appropriate shape using, for example, vacuum forming techniques. This provides an extra layer of protection for the foil to guard against ripping or tearing over the life of the laser safety enclosure  50 . It also may improve the aesthetic appearance of the inside of the laser cabinet  10 .  
         [0061]     In another preferred embodiment of the laser safety enclosure  52  shown in  FIG. 4 , a plastic layer  68  is the outer enclosure, and a metal layer  70  is the inner laser containment structure. The metal layer  70  may be made separately, for example by using the same type of vacuum forming technique employed for the plastic and metal laminate of the first and second embodiments or by stamping or other methods if quantities permit. This allows the metal layer  70 , for example, aluminum foil, to be made in the appropriate shape to mate to the interior surface  72  of an injection molded or cast housing, such as plastic layer  68  forming the outer enclosure. The metal layer  70  may be attached to the interior surface  72  of the plastic layer  68  using an adhesive between the layers  68 ,  70  or using any known type of mechanical fasteners  74 , as shown in  FIG. 4 .  
         [0062]     Alternatively, as shown in  FIG. 5 , in another embodiment, the laser safety enclosure  54  has a plastic layer  68  as the outer enclosure, and a metal layer  70  as the inner laser containment structure, with the metal layer  70  spaced from the interior surface  72  of the plastic layer  68 , and with the mechanical fasteners  74  being attached to bosses  76  on the interior surface  72  of the plastic layer  68 .  
         [0063]     In another preferred embodiment of the laser safety enclosure  56  shown in  FIG. 6 , a plastic housing  78  forms the outer enclosure and a metal layer  80  forms the inner laser containment structure, with the metal layer  80  including laser blocking material which may be applied in the form of a metal powder that is sprayed or sintered to the interior surface  82  of the plastic housing  78  to form the metal layer  80  attached thereto with a sufficient thickness for laser beam confinement.  
         [0064]     In yet another preferred embodiment of the laser safety enclosure  58  shown in  FIG. 7 , the inner laser containment structure  84  of the laser safety enclosure  58  includes metal powder which may be mixed into a plastic resin to create a formable composite material having the appropriate heat dissipation and laser beam containment characteristics. An outer enclosure of plastic or other materials for retaining the inner laser containment structure  84  may be optionally provided. The composite material may thereafter be formed into the wall portions forming the upstanding walls  26 ,  30  and the base member  32  of the laser safety enclosure  58 .  
         [0065]     It is understood that the laser safety enclosure  12  of  FIG. 1  and its various example embodiments  48 - 58  shown in  FIGS. 1-8  may be configured, dimensioned, and oriented in any known manner within the outer housing  14 , with or without the window  42  through the outer housing  14 . For example, the laser safety enclosure  12  may form a completely enclosed box such as a sealed or sealable enclosure, as shown in an alternative embodiment in  FIG. 8 , which is lined with and/or which includes the laser blocking material for retaining the laser beam  22  therein.  
         [0066]     In the alternative embodiment shown in  FIG. 8  in a side cross-sectional view, a laser safety enclosure  86  is shown in accordance with a seventh preferred embodiment of the present invention, in which the interior space  34  is substantially completely enclosed and/or sealed in all three directions, with only the X-Z cross-sectional view being shown in  FIG. 8 . In a further alternative embodiment, the laser safety enclosure  86  may include at least one window and/or a door as described herein with respect to the embodiment shown in  FIG. 1 , allowing the user to insert and remove the workpiece  20  and allowing the user to view the operation of the laser beam  22  for cutting, engraving and/or etching the workpiece  20 .  
         [0067]     It is understood that some structures may optionally extend through the upstanding walls  26 ,  30  or the base member  32  of the substantially completely enclosed and/or sealed laser safety enclosure  86 , such as control wires from a control device  16 , such as shown in  FIG. 1 , to the moveable carriage  24  for causing the moveable carriage  24  and/or any motion system attached to the moveable carriage  24  to move and/or to be controlled during the laser operations of the laser device behind the wall  28  which generates the laser beam  22 .  
         [0068]     In the alternative embodiment shown in  FIG. 8 , the laser safety enclosure  86  may be a rigid monolithic unit without a window  42  or other apertures therethrough, with the laser safety enclosure  86  formed by the upstanding walls  26 ,  30  and base member  32  as well as an upper wall portion  88 . Such wall portions forming the upstanding walls  26 ,  30 , the base member  32 , and the upper wall portion  88  may include combinations and/or compositions of materials, such as rigid outer enclosures and inner laser containment structures, formed from the layers combined to form the wall portions as described herein in connection with the first embodiment of the laser safety enclosure  48  of  FIG. 2 .  
         [0069]     It is understood that the rigid upstanding walls  26 ,  30 , the base member  32 , and the upper wall portion  88  may alternatively include such combinations and/or compositions of materials shown and described in the various embodiments  50 - 58  in  FIGS. 3-7 .  
         [0070]     Optionally, the laser safety enclosure  86  of  FIG. 8  may include an integrated unit from the juxtaposition of a top member  90  and a bottom member  92  forming, for example, approximate halves of the laser safety enclosure  86 , with a substantially closed seam  94  between the juxtaposed top member  90  and bottom member  92 . Accordingly, the members  90 ,  92  may be separated to insert the workpiece  20  into the interior space  34 , and the members  90 ,  92  may then be juxtaposed together as shown in  FIG. 8  during laser operations by the laser device creating the laser beam  22 . In an example embodiment, the members  90 ,  92  may be connected together by a hinge to open and close the substantially sealed laser safety enclosure  86 . For example, the top member  90  may be attached to the door  38  in  FIG. 1  to swing away from the bottom member  92  for inserting the workpiece  20  into the interior space  34 .  
         [0071]     The laser safety enclosure  12  and its various example embodiments  48 - 58  and  86  shown in  FIGS. 1-8 , respectively, and constructed in accordance with the present invention, provide many advantages over the enclosures of the prior art. The invention allows the use of a wide range of plastic fabrication methods such as injection molding, casting and vacuum forming, which may provide significant cost savings over sheet metal techniques at various quantity levels.  
         [0072]     The invention may also take advantage of relatively inexpensive materials, such as acrylic, polycarbonate, urethane, and acrylonitrile-butachene-styrene (ABS) for the exterior material, and aluminum or copper for the interior material.  
         [0073]     In addition, the invention allows for a much wider range of shapes for the enclosure of the laser product than does standard bending and welding of sheet metal, thus allowing for an improvement in aesthetics, functionality, and overall product appeal to the consumer.  
         [0074]     Use of the present invention also means that the tooling costs for complex shapes are significantly less than those for stamping sheet metal, and plastic fabrication is much more suited to mass production than standard bending and welding of sheet metal.  
         [0075]     While the preferred embodiment of the present invention has been shown and described herein, it will be obvious that such embodiment is provided by way of example only. Numerous variations, changes and substitutions will occur to those skilled in the art without departing from the invention herein. Accordingly, it is intended that the invention be limited only by the spirit and scope of the appended claims.