Patent Publication Number: US-7210798-B2

Title: Image projection lighting device and control system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   Not applicable. 
   STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
   Not applicable. 
   BACKGROUND OF THE INVENTION 
   The embodiments of the present invention generally relate to lighting systems that are digitally controlled and to the lighting fixtures used therein, in particular multiparameter lighting fixtures having one or more image projection lighting parameters. 
   Lighting systems are typically formed by interconnecting, via a communications system, a plurality of lighting fixtures and providing for operator control of the plurality of lighting fixtures from a central controller. Such lighting systems may contain multiparameter light fixtures, which illustratively are light fixtures having two or more individually remotely adjustable parameters such as focus, color, image, position, or other light characteristics. Multiparameter light fixtures are widely used in the lighting industry because they facilitate significant reductions in overall lighting system size and permit dynamic changes to the final lighting effect. Applications and events in which multiparameter light fixtures are used to great advantage include showrooms, television lighting, stage lighting, architectural lighting, live concerts, and theme parks. Illustrative multi-parameter light devices are described in the product brochure entitled “The High End Systems Product Line 2001” and are available from High End Systems, Inc. of Austin, Tex. 
   Prior to the advent of relatively small commercial digital computers, remote control of light fixtures from a central controller was done with either a high voltage or low voltage current; see, e.g., U.S. Pat. No. 3,706,914, issued Dec. 19, 1972 to Van Buren, and U.S. Pat. No. 3,898,643, issued Aug. 5, 1975 to Ettlinger, both of which are incorporated by reference herein for all purposes. With the widespread use of computers, digital serial communication was widely adopted as a way to achieve remote control; see, e.g., U.S. Pat. No. 4,095,139, issued Jun. 13, 1978 to Symonds et al., and U.S. Pat. No. 4,697,227, issued Sep. 29, 1987 to Callahan, both of which are incorporated by reference herein for all purposes. 
   In 1986, the United States Institute of Theatre Technology (“USITT”) developed a digital communications system protocol for multiparameter light fixtures known as DMX512. Basically, the DMX512 protocol is comprised of a stream of data which is communicated one-way from the control device to the light fixture using an Electronics Industry Association (“EIA”) standard for multipoint communications know as RS-485. 
   A variety of different types of multiparameter light fixtures are available. One type of advanced multiparameter light fixture, which is referred to herein as an image projection lighting device (“IPLD”), uses a light valve to project images onto a stage or other projection surface. A light valve, which is also known as an image gate, is a device, such as a digital micro-mirror (“DMD”) or a liquid crystal display (“LCD”), that forms the image that is to be projected. Various IPLD&#39;s and IPLD systems are described in U.S. patent application Ser. No. 10/190,926, filed Mar. 4, 2002, U.S. patent application Ser. No. 10/206,162, filed Jul. 26, 2002, and U.S. patent application Ser. No. 10/290,660, filed Nov. 8, 2002, all of which are incorporated by reference herein for all purposes. 
   In their common application, IPLD&#39;s are used to project their images upon a stage or other projection surface. Control of the IPLD&#39;s is affected by an operator using a central controller that may be located several hundred feet away from the projection surface. In many applications, the stage, or projection surface, is also elevated such that, with the central controller located at a significant distance from the stage, the operator can not see the image projected upon the stage. This lack of vision may prevent effective control of the projected images from the central controller. For example, the operator may not be able to set the desired focus parameter value of the image, or set the projected image to the desired position, upon a remote projection surface because the operator may not be able to see the projection surface from the central controller location. 
   In a given application, there may be up to hundreds of IPLD&#39;s used to illuminate the projection surface, with each IPLD having many parameters that may be adjusted to create a scene. Once a scene is constructed, the operator of the central controller can adjust the parameters of the many IPLD&#39;s in order to construct a new scene. The work of adjusting or programming the parameters to the desired values for the many IPLD&#39;s to create a scene can take quite some time. Many times the scenes are created by the operator during a rehearsal and the time for programming the many IPLD&#39;s has limitations. 
   Since the operator of the control system often can not see the projected images from the central controller location, the desired focus, position or other parameters of the IPLD&#39;s may be set with the operator having a human spotter in proximity to the stage or projection surface. The spotter can communicate verbally, such as over a radio, to give directions to the operator as to when the desired image or effect is achieved. In certain applications, a portable remote control unit of the central controller can be used by the operator in close proximity to the stage or projection surface for setting the focus, position or other parameter of the image projected upon projection surface. Although this eliminates the spotter, the operator can not see the projected images from the central controller, making last minute adjustments difficult. 
   Thus, there remains a need in the art for methods and apparatus for improving the control system of a remotely located IPLD. The embodiments of the present invention are directed to methods and apparatus for improved lighting devices and complimentary control systems that seek to overcome the limitations of the prior art. 
   SUMMARY OF THE PREFERRED EMBODIMENTS 
   The methods and apparatus of certain embodiments of the invention provide a camera integral to a particular image projection lighting device (IPLD) in order to capture the projected image from the particular IPLD. The captured image can then be sent over a communication system to the operator for viewing on a visual display device such as a computer monitor on a central controller. Using the captured image of the projected image, as viewed upon the display device, the operator may then, using the central controller, adjust the focusing, position, or other parameters of the projected image upon the stage or projection surface to the desired value. The captured image may also be used, such as by a central control system, to automatically, and without operator intervention, adjust parameters of the IPLD to desired values. 
   In a first embodiment, a lighting system includes an IPLD with an integral camera, a central controller, and a communications system. The system is used to provide a visual image for visualization, by an operator on a visual monitoring device located at the central controller, of the projected image that is projected upon a projection surface by a particular IPLD. The visual image as provided by the visual monitoring device is viewed by an operator of the central controller and used as a visual feedback aid as to the parameter settings of a particular IPLD. The visual feedback is then used by the operator to provide parameter adjustment commands to the particular IPLD from the central controller over the communications system. 
   In a second embodiment, a lighting system includes an IPLD with a camera, a central controller, and a communications system. The system is used to provide a visual image for visualization, by an operator from a visual monitoring device located at the central controller, of the projected image that is projected upon a projection surface by a particular IPLD. The operator uses the central control system to send camera focus commands over the communication system to a particular IPLD to adjust the camera focus for the best focus of the projected image projected by the particular IPLD upon the projection surface. The camera focus command values are used by the microprocessor of the particular IPLD to automatically adjust the focus of the projection focusing lens in order to focus the projected image on the projection surface. In this way, the operator of the central controller need only adjust the focus of the camera of the particular IPLD on the projection surface in order to automatically affect the correct focus of the projected image on the projection surface. 
   In a third embodiment, an IPLD includes a camera equipped with an auto focusing system for adjusting the focus of the camera to best capture an image of the projection surface in the camera&#39;s field. As the camera auto focusing system affects a change in focus, the camera communicates focusing values that are sent to the microprocessor of the IPLD where they are used to adjust the projection focusing lens of the IPLD to provide for the best focus of the projected image on the projection surface. 
   In a fourth embodiment, an IPLD includes a camera equipped with a focusing system for adjusting the focus of the camera to best capture an image in the camera&#39;s field. As the projection focusing lens is adjusted to provide for a desired focus on the particular projection surface, the projection focusing values are used by the processor of the IPLD to calculate camera focusing values. The camera focusing values are then sent to the camera to obtain a focus of the captured images on the projection surface. 
   In a fifth embodiment, an IPLD includes a camera equipped with a focusing system for adjusting the focus of the camera to obtain a desired focus of the captured camera images from the projection surface. The captured camera image data is sent to the processor of the IPLD, which analyzes the camera image data to provide focus values that bring the projected image into focus on the particular projection surface. 
   Thus, the present invention comprises a combination of features and advantages that enable it to improve the controllability and operability of a lighting system having one or more IPLD&#39;s. These and various other characteristics and advantages of the present invention will be readily apparent to those skilled in the art upon reading the following detailed description of the preferred embodiments of the invention and by referring to the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     For a more detailed understanding of the preferred embodiments, reference is made to the accompanying Figures, wherein: 
       FIG. 1  is a schematic view of one embodiment of an image projection lighting system; 
       FIG. 2  is a front view of an image projection lighting device for use with the embodiment of  FIG. 1 ; 
       FIG. 3  is a block diagram showing components within a base housing and within a lamp housing of an image projection lighting device for use with the embodiment of  FIG. 1 ; 
       FIG. 4  is a schematic diagram showing a projection surface at a first distance from an image projection lighting device in accordance with an embodiment of the present invention; and 
       FIG. 5  is a schematic diagram showing a projection surface at a second distance from an image projection lighting device in accordance with an embodiment of the present invention 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   In the description that follows, like parts are marked throughout the specification and drawings with the same reference numerals, respectively. The drawing figures are not necessarily to scale. Certain features of the invention may be shown exaggerated in scale or in somewhat schematic form and some details of conventional elements may not be shown in the interest of clarity and conciseness. The present invention is susceptible to embodiments of different forms. There are shown in the drawings, and herein will be described in detail, specific embodiments of the present invention with the understanding that the present disclosure is to be considered an exemplification of the principles of the invention, and is not intended to limit the invention to that illustrated and described herein. It is to be fully recognized that the different teachings of the embodiments discussed below may be employed separately or in any suitable combination to produce the desired results. 
   In particular, various embodiments of the present invention provide a number of different methods and apparatus for operating and controlling multiple IPLD lighting systems. The concepts of the invention are discussed in the context of IPLD lighting systems but the use of the concepts of the present invention is not limited to IPLD systems and may find application in other lighting and other visual systems where control of the system is maintained from a remote location and to which the concepts of the current invention may be applied. 
     FIG. 1  shows an apparatus  10  comprised of a central controller  150 , a communications interface  138 , an IPLD (image projection lighting device)  102 , an IPLD  104 , and an IPLD  106 . The IPLDs  102 ,  104 , and  106  are electrically connected by communications lines  142 ,  144 , and  146 , respectively, to the communication interface  138 . The communications interface  138  is electrically connected to the central controller  150  by communications line  136 . The central controller  150  may be a dedicated control console or a computer system. The central controller  150  has a visual display monitor  152 , a keypad entry device  154  and entry adjuster devices  156 . 
   Three IPLD&#39;s,  102 ,  104 , and  106  are shown for simplification. However, many more IPLD&#39;s, for example thirty IPLD&#39;s, each one like any one of  102 ,  104 , and  106  could be used in a lighting system or apparatus, such as apparatus  10 . The communication interface  138  may be a router or hub as known in the communications art. 
     FIG. 2  shows a front view of one embodiment of IPLD  102 , including a base or electronics housing  210 , a yoke  220 , and a lamp housing  230 . The IPLDs  104  and  106  of  FIG. 1  may each be identical to the IPLD  102  of  FIG. 2 . 
   The base housing  210  of the IPLD  102  includes a connection point  212  for electrically connecting a communications line, such as communications line  142  shown in  FIG. 1 . The yoke  220  is physically connected to the housing  210  by a bearing  225  which allows the yoke  220  to pan or rotate in relation to the electronics housing  210 . The lamp housing  230  is rotatably connected to the yoke  220 . The lamp housing  230  typically contains optical components. An exit aperture  240  is shown for projecting light from a main projection lamp inside the lamp housing  230 . An aperture  248  is shown for allowing a camera  364  (as shown in  FIG. 3 ), within the lamp housing  230  to receive and capture images. 
     FIG. 3  is a block diagram showing components within or part of the base housing  210  and within or part of the lamp housing  230  of the IPLD  102 .  FIG. 3  also shows the central controller  150 . 
   The components of the base housing  210  include a communication port (shown as “comm port”)  311 , image control  312 , memory  315 , microprocessor  316 , video control interface  317 , motor control  318 , lamp power supply control  319 , motor power supply  320 , and lamp power supply  321 . 
   The components of the lamp housing  230  include a filter assembly  342 , a light collection mirror  344 , a main projection lamp or main projection light source  345 , a light valve  346 , a condensing lens  347 , a filter assembly  349 , a projection focusing lens  351 , a motor lead screw assembly  376  for focusing the lens  351 , and a window aperture  370 . 
   The central controller  150  outputs address and control commands over a communications system which may include communications interface  138  of  FIG. 1 . The communications interface  138  is connected to the communication port  311  by communications line  142  as shown in  FIG. 3 . The image control interface  312  of the electronics housing  210  provides control signals to the light valve  346  in the lamp housing  230 . Although the central controller  150  and the communications interface  138  are shown connected by communication wires  138  and  142  to IPLD  102 , the communication wires  138  and  142  could be substituted with a wireless system using infrared, ultrasonic, or radio-frequency transmissions. 
   The microprocessor  316  in the electronics housing  210  provides control signals to the image control  312 . The microprocessor  316  is shown electrically connected to the memory  315 . The memory  315  stores the computer software operating system for the IPLD  102  and possibly different types of content used to form images at the light valve  346  of the lamp housing  230 . 
   The light valve  346  may preferably be a transmissive type light valve where light from the projection lamp is directed to the light valve to be transmitted through the light valve to the lens. In alternative embodiments, the light valve may also be a reflective light valve where light from the main projection lamp is directed to the light valve to be reflected from the light valve to the lens. 
   The motor control  318  is electrically connected to the motors. The electrical connection to the motors is not shown for simplification. The motors may be stepping motors, servomotors, solenoids or any other type of actuators. The motor control interface  318  provides the driving signals to the motors used with filter assemblies  342  and  349 . Filter assemblies  342  and  349  may be rotatable aperture wheels. The aperture wheels, if used for filter assemblies  342  and  349 , may be used to vary color or pattern parameters. 
   The motor control  318  is electrically connected to receive control signals from the microprocessor  316 . Two power supplies  320 ,  321  are shown in  FIG. 3 . A motor power supply  320  is shown for supplying energy to the motors and a lamp power supply  321  is shown for supplying power to the main projection light source or lamp  345 . A lamp power supply interface  319  is electrically connected to the microprocessor  316  to receive control signals from the microprocessor  316  and signals are sent from the lamp power supply interface  319  to the lamp power supply  321  for controlling the main projection light source or lamp  345 . 
   The IPLD  102  may include at least two different housings, such as the base or electronics housing  210  and the lamp housing  230  to facilitate remote positioning of the lamp housing  210  in relation to the base  230 . The lamp housing  230  contains the optical components used to project light images upon a stage or projection surface  399  from projection focusing lens  351  in the direction of arrow  380 , outwards from the IPLD  102 . The lamp housing  230  may be connected to a bearing mechanism  225  that facilitates pan and tilting of the lamp housing  230  in relation to the base or electronics housing  210 . The bearing mechanism  225  is shown simplified. The motors that would be used for pan and tilt are not shown for simplification. 
   The window aperture  370  of the lamp housing  230  is shown in  FIG. 3 , for allowing input light for the reception of images traveling in the direction of arrow  382  from the projection surface  399  to be captured by the camera  364 . The camera  364  may be a type of camera (known in the art) that receives light images with a contained camera sensor and converts the light images into electronic image data or signals. The camera  364  may be of a type, as known in the art, which may be constructed of only a camera sensor or the camera  364  may contain other optical components in the camera sensor optical path along with suitable control and communication electronics. 
   The main projection lamp  345  has its light energy collected by the collecting mirror  344  and a condensing lens  347 . The collected light from the main projection lamp  345  passes through the condensing lens  347 . Next, the light passes though filter assemblies  342  and  349  and through the light valve  346 . Finally, the light passes through the projection focusing lens  351  and travels in the direction of the arrow  380  towards the projection surface  399 . 
   The video control interface  317  of the electronics housing  210  sends image data received from the camera  364  to the microprocessor  316 . The video control interface  317  may also be used to send command signals and value data to and from the microprocessor  316  and to and from the camera  364 . The video control interface may be a separate interface or processing system or may be part of the processor  316 . The microprocessor  316  may send this image data or signals to the communications port  311  for transmission back to the central controller  150  or to other IPLDs on the communications system or apparatus  10 , such as IPLDs  104  and  106  connected to communication interface  138  in  FIG. 1 . The communications port  311  may be a part of the processor  316 . The communications port  311  can be any device capable of receiving the communication sent over the communication system. 
   The other IPLDs on the network or apparatus  10 , such as IPLD  104  and IPLD  106 , may use the image data received from the IPLD  102  by projecting the images that were captured by the camera  364  and thus originated at IPLD  102 . The general capturing of images and sending image data to other lighting devices is described in detail in pending U.S. patent application Ser. No. 10/090,926, to Richard S. Belliveau, one applicant herein, Publication No. 2002-0093296, filed on Mar. 4, 2002, titled “Method, Apparatus And System For Image Projection Lighting”, which is incorporated by reference herein for all purposes. 
     FIG. 4  shows a projection surface  410  at a distance of approximately D 1 S from an image projection lighting device lamp housing  230   b  of (IPLD)  102   a . Dotted lines  490   a  and  492   a  show the camera field outside of the lamp housing  230   a . The camera field, shown by  490   a  and  492   a , is established by a camera optical path  382   b  of the camera  364 . Dotted lines  494   a  and  496   a  show the projection field outside of the lamp housing  230   a . The projection field is established by a projection lamp optical path  380   b . The lamp housing  230   a  is similar to the lamp housing  230  of  FIG. 3  except that some of the optical components are omitted for simplification. A focusing lens  468  is shown as a component of the camera  364 . The camera may have only one sensor capable of capturing visual images and converting them into electronic signals or the camera may contain other components in the camera&#39;s housing. The camera&#39;s sensor is shown as  470 . A distance D 1 F is the distance from the focusing lens  351  to the motor  466 . 
   A bearing  225  is shown, which may be identical to the bearing  225  of  FIGS. 2 and 225  of  FIG. 3 . An electronics housing  210  is shown which may be identical to the electronics housing  210  of  FIG. 3 . A communications cable  142  is shown that may be identical to the communications cable  142  of  FIG. 1  and  FIG. 3 . A motor lead screw assembly  376  is shown for focusing the lens  351 . The motor lead screw assembly  376  is broken down into individual components, with motor  466  shown with a lead screw shaft  464  threaded into a power nut bracket  462 . The power nut bracket  462  is attached to the focusing lens  351 . The lens  351  may be identical to the lens  351  of  FIG. 3 . The camera  364  may be identical to the camera  364  of  FIG. 3  and is shown with window  370  that may be identical to the window  370  of  FIG. 3 . 
     FIG. 5  shows a projection surface  410  at a distance of approximately D 2 S from IPLD  102   a . Dotted lines  490   b  and  492   b  show the camera field outside of the lamp housing  230   a . The camera field is established by the camera optical path  382   b . Dotted lines  494   b  and  496   b  show the projection field outside of the lamp housing  230   a . The projection field is established by the projection lamp optical path  380   b . The lamp housing  230   a  is similar to the lamp housing  230  of  FIG. 3  except that some of the optical components are omitted for simplification. A focusing lens  468  is shown as a component of the camera  364 . The camera may have only one sensor capable of capturing visual images and converting them into electronic signals or the camera may contain other components in the camera&#39;s housing. 
   The camera&#39;s sensor is shown as  470 . A bearing  225  is shown that may be identical to the bearing  225  of  FIGS. 2 and 225  of  FIG. 3 . An electronics housing  210  is shown which may be identical to the electronics housing  210  of  FIG. 3 . A communications cable  142  is shown which may be identical to the communications cable  142  of  FIG. 1  and  FIG. 3 . A motor lead screw assembly  376  is shown for focusing the lens  351 . The motor lead screw assembly  376  is broken down in to individual components, with motor  466  shown with a lead screw shaft  464  threaded into a power nut bracket  462 . The power nut bracket  462  is attached to the focusing lens  351 . The lens  351  of  FIG. 5  may be identical to the lens  351  of  FIG. 3 . 
   A distance D 2 F is the distance from the projection focusing lens  351  to the motor  466 . A camera  364  may be identical to the camera  364  of  FIG. 3  and is shown with a window  370  that may be identical to the window  370  of  FIG. 3 . 
   Referring back to  FIG. 1 , lighting system  10  is controlled by an operator (not shown) using the central controller  150  and input devices  154  and  156  to input commands to the lighting devices (IPLD&#39;s)  102 ,  104  and  106 . While only three IPLD&#39;s are shown, up to hundreds of IPLD&#39;s may be used with the lighting system  10 . The commands input to the central controller  150  by the operator are used to adjust the parameters of the IPLD&#39;s. A communications line  136  is connected to a communications interface  138  (which may be a hub or switch as known in the communications art). The communications interface relays the commands sent by the central controller  150  over the communications lines  142 ,  144  and  146  to IPLD&#39;s  102 ,  104  and  104  respectively. 
   The commands are sent from the central controller to adjust the position of the lamp housing  230  of  FIG. 2  in relation to the yoke  220  (this may be known in the art as tilting the lamp housing). Also the lamp housing  230  and yoke  220  may be commanded by the central controller to change their position relative to the base or electronics housing  201  (this may be known in the art as panning the lamp housing). The commands from the central controller to the IPLD&#39;s may be used to adjust other parameters of the individual IPLD&#39;s such as image, color, focus, and intensity, as well as other parameters of the projected light. 
   When the operator and the central control system  150  are located a great distance from the IPLD&#39;s  102 ,  104  and  106  and the projection surface  410 , the operator may not be able to see in order to correctly adjust the parameters of the IPLD&#39;s upon the projection surface. For example, if the operator can not see the projected image, the operator may not know if the position of the projected image on the projection surface is correct. If the operator can not see the projected image, it is difficult for the operator to set the desired focus of the IPLD upon the projection surface. 
   In order to adjust the parameters of a particular IPLD, the operator first selects, via input keypad  154 , the particular IPLD to command. This is done by sending an operating address over the communication system to be recognized by only the particular IPLD. The action of sending addresses and commands over a communication system from the central controller to the IPLD&#39;s is known in the art. Once the particular IPLD has been selected, the operator next chooses the parameter to be adjusted. If a command is sent by the operator to a particular IPLD (such as IPLD  102 ) to adjust a parameter by inputting to the keypad  154  or adjuster devices  156 , the communications port  311  of IPLD  102  receives the command and forwards the command to the processor  316 . The processor receives the commands and determines the necessary action by operating with the memory  315  to determine the correct control signals to be sent to adjust the parameter. 
   The parameter may be the image parameter. In the case of an image parameter, the processor  316  may send control signals to the image control device  312  that in turn sends the appropriate signals to the light valve  346  to vary the image parameter (change the look of the projected image). An image parameter is the parameter that controls the light valve or light valves. The light valve or valves can also be used to vary an intensity (brightness) parameter by controlling the amount of light available to be projected on the stage or projection surface. 
   If the command from the central controller  150  is a command to vary the position of the lamp housing in relation to the base for remotely controlling the position of the projected image on the projection surface, the communications port  311  receives the command and forwards the command to the processor  316 . The processor receives the commands and determines the necessary action by operating with the memory  315  to determine the correct control signals to be sent to the motor control interface  318 , which, in turn, sends the correct driving signals over wires (not shown) to drive the motors for pan and tilt (not shown). 
   If the command from the central controller  150  is a command to vary the focus of the projection focusing lens  351 , the communications port  311  receives the command and forwards the command to the processor  316 . The processor receives the commands and determines the necessary action by operating with the memory  315  to determine the correct control signals to be sent to the motor control interface  318  which in turn sends the correct driving signals over wires (not shown) to drive the focus motor and lead screw assembly  376  which in turn linearly moves the focusing lens to achieve the best focus of the projected image for the distance required to the projection surface. 
   If the focus parameter of a particular IPLD is selected for adjustment by the operator of the lighting system  10  using the central controller  150 , the visual display device, such as a computer monitor  152 , cooperatively displays the images of the projected images on the projection surface as captured by the camera  364 . The camera  364  is preferably integrated into the IPLD  102  so that it can capture the projected images as created with the light valve  346  and the main projection lamp  345 . The optical path of the main projection lamp used for producing the light for the projected images is shown in the direction of arrow  380  of  FIG. 3 . 
   The optical path of the camera  364  used for capturing the projected images is shown in the direction of arrow  382 . The area of the projection surface image that the camera is able to capture is determined by the camera field and the camera field is created by the camera optical path. The camera field is shown in  FIG. 4  by dotted lines  490   a  and  492   a . The cameras optical field at the projection surface  410  of  FIG. 4  captures more than the entire projection field at the projection surface  410 . The projection field is shown if  FIG. 4  by dotted lines  494   a  and  496   a . The projection field is created by the main projection lamp optical path as shown by arrow  380   b . It is preferable to have a camera field larger than the projection field so that not only the entire projection field on the projection surface is captured by the camera but also some of the surrounding areas of the projection surface are captured. 
   When the operator of the central control system  150  selects an IPLD to adjust a parameter (such as IPLD  102  of  FIG. 1  or IPLD  102   a  of  FIG. 4 ), the action of selecting the IPLD, by input to an input device such as  154  or  156  of the central control system, cooperatively provides the cameras captured image of the projection surface projected upon by IPLD  102  onto the visual display device  152 . 
   The communication system used with lighting system  10  of  FIG. 1  may send command and address signals from the central controller  150  of  FIG. 1  to the IPLDs  102 ,  104  and  106 . The IPLDs  102 , 104  and  106  may send captured camera video information as requested by the central controller to the central controller as explained in detail in pending United States patent application titled “Method, Apparatus And System For Image Projection Lighting”, inventor Richard S. Belliveau, Publication No. 2002-0093296, Ser. No. 10/090,926, filed on Mar. 4, 2002, incorporated by reference herein. That application describes prior art IPLDs with cameras and communication systems that allow camera content, such as in the form of digital data, to be transferred between prior art IPLDs. 
   During the programming of the IPLD&#39;s for an event or rehearsal, the operator of the central controller  150  of  FIG. 1  need only select the particular IPLD from a plurality of IPLD&#39;s. The selection of the particular IPLD is accomplished by sending the appropriate address, as input by the operator of the central control system  150  of  FIG. 1 , to be recognized by a particular IPLD. The particular IPLD recognizing the correct address can respond by cooperatively sending the captured camera images back over the communication system to be received by the central controller. The central controller receives the captured images from the selected IPLD and electronically provides the images to the visual display device or computer monitor  152 . In this way, the camera captured images from a particular IPLD that has been selected by the operator of the central control system are sent automatically back to the central controller to be displayed on the visual display device. The triggering of the event to view the captured images of a selected IPLD only requires the selection of the particular IPLD by the operator of the central controller. 
   The triggering of the event to view the captured images of a selected IPLD on the visual display device of the central controller may also be actuated after the IPLD has been selected by the central controller. A known input entry device such as the keypad  154  or adjuster devices  156  available on the central controller  150  of  FIG. 1  may at any desired time (when correctly inputted or adjusted by the operator) provide the operator with the camera captured images of the selected IPLD to be viewed on the visual display device  152  of  FIG. 1 . 
   The operator uses the camera captured images from the IPLD as displayed by the display device  152  of  FIG. 1  as an aid to see the projected images on the projection surface, even though the central controller may be located at a distance or location where the operator of the central controller can not see the images projected on the projection surface directly. By using the captured camera images from the selected IPLD as displayed on the central controller display device or computer monitor, the operator can adjust parameters of the selected IPLD. 
   The operator can see (by looking at the visual display device of the central controller) if the focus of the projected image on the projection surface needs to be adjusted, and if it does, the operator can input commands through the central controller to adjust the focus lens of the particular IPLD. The operator can see by looking at the visual display device of the central controller if the position of the projected image on the projection surface is located in the desired position as determined by the operator. If an adjustment to the projected image of the selected IPLD is needed, the operator sends the appropriate position commands to the selected IPLD to adjust position (or pan and tilt) to place the projected image in the desired location on the projection surface. 
   The operator of the lighting system  10  of  FIG. 1  of the invention may adjust several different parameters of a selected IPLD with the central controller by viewing on the visual display of the central controller the captured camera images of the projected of images on the projection surface as projected by the selected IPLD. Adjustable parameters of a selected IPLD that may be adjusted by the operator (when viewing the captured camera image of the selected IPLD on the visual display device) may include focus, position, color adjustment, image, and intensity. For adjusting position it is not necessary for the selected IPLD to be actually projecting. 
   The captured camera images of the projection surface without the projected image may be all that is needed by the operator to estimate where the projected images are going to appear on the projection surface and position the IPLD to the best estimated position for the desired location. The captured camera image may also be used to simply check or confirm by the operator that the selected IPLD is operational and performing the desired parameters on the projection surface. 
     FIG. 4  shows a lamp housing  230   a  similar to the lamp housing  230  of  FIG. 3 . Lamp housing  230   a  of  FIG. 4  has been simplified by not showing all of the components shown in the lamp housing  230  of  FIG. 3 . The focusing lens  351  of  FIG. 4  is shown and is similar to the focusing lens  351  of  FIG. 3 . Different means for mechanizing the projection focusing lens  351  for remote control of focus are known in the art. The means shown in  FIG. 4  shows the focusing lens  351  attached to a power nut  462  that is in turn linearly driven by lead screw shaft  464  that is attached by any suitable means to the motor  466 . The motor  466  is fixed to the lamp housing  230   a  by any suitable means. As the lead screw  464  is rotated, the power nut  462  with the focusing lens  351  moves towards or away from the motor  466 . 
   The movement of the lens  351  by the motor lead screw drive allows remote control of the focus of the lens  351 . The motor  466  is driven by control signals from the motor control interface  318  of  FIG. 3 . The motor control interface  318  of  FIG. 3  receives control signals from the processor  316 . The communications port  311  of  FIG. 3  receives commands over the communication system from the central controller  150  of  FIG. 1 , and the communications port  311  passes these control commands to the processor  316  for remote control of the projection focusing lens  351 . The remote control of a focus lens in a multiparameter light by a central controller is known in the art. 
   Motor  466  of  FIG. 4  may be a stepping motor or a servo motor or any actuator that can be incrementally controlled by the processor  316  of  FIG. 3 . The incremental control of the motor  466  by known values allows the operator of the central controller  150  to precisely position the projection focusing lens  351  with values. For example, if the projection focusing lens  351  of  FIG. 4  needs to move 8 mm from the motor  466  to obtain the proper focus of the image on the projection surface  410 , a value of “8” may be selected from the central controller  150 . The focus value change commands sent from the central controller  150  to control the projection focus parameter as received by the image projection lighting device  102  controls the projection focusing lens  351  distance D 1 F of  FIG. 4  and D 2 F of  FIG. 5 . 
   The camera  364  of  FIG. 4  includes camera sensor  470  and focusing lens  468 . A distance marked as D 1 C indicates the distance of the focusing lens  468  to the sensor  470 . The correct value of the distance required from the focusing lens  468  to the camera sensor  470  to bring the image on the projection surface  410  into the desired focus is shown as D 1 C. 
   The distance between the camera focusing lens  468  and the sensor  470  will vary with the distance of the projection surface  410  to the lamp housing  230   a . It is possible to establish a documented relationship where a known distance from the lens  468  to the sensor  470  can result in a desired focus at a known distance to the projection surface.  FIG. 5  shows the same invention of  FIG. 4  but with the distance D 2 S to the projection screen  410  reduced from that of  FIG. 4 . As the distance D 2 S of  FIG. 5  is reduced over that of D 1 S of  FIG. 4 , the other distances are increased such as D 2 F and D 2 C of  FIG. 5  over that of D 1 F and D 1 C of  FIG. 4 . 
   There can be a documented relationship between D 1 S (distance to the projection surface from the lamp housing  230   a ) of  FIG. 4  and values of D 1 C (the camera focus value) and D 1 F (the projection focus value). This documented relationship can be stored in the memory  315  of  FIG. 3  of the IPLD  102 . The documented relationship can be a lookup table or a mathematical formula like a ratio. 
   For example, if in  FIG. 4  D 1 S is 1600 cm, D 1 C is 8 mm and D 1 F is 4 mm and in  FIG. 5  if D 2 S is 800 cm, D 2 C is 16 mm and D 2 F is 8 mm we can find that the projection focusing value is 50% of the camera focusing value. Or we could establish that the camera focusing value would be 2× the projection focusing value. The relationship of the camera focusing value and the projection focusing value can be documented in the memory  315  as a ratio. 
   It may not always be easy to come up with a simple ratio for the camera focusing lens and the projector focusing lens. In this case a lookup table can be used to provide the documented relationship in the memory  315 . For each particular distance to the projection surface such as D 1 S of  FIG. 4 , a camera focusing value D 1 C and a projection focusing value D 1 F are documented. By documenting several particular projection surface distances and the values required for camera focusing and projection focusing at those particular projection surface distances, a relationship of the camera focusing values and the projection focusing values can be documented in the memory  315 . 
   If the documented relationship is kept in the memory of the IPLD such as memory  315  of  FIG. 3 , then the processor can use this relationship to automatically adjust the projection focusing lens  351  of  FIG. 4  to a value when the camera focusing lens  470  is moved to a known focus value to achieve the correct focus on the projection surface  410 . 
   The operator of the central controller  150  of  FIG. 1  would first select a particular IPLD by sending an address. Next the operator may select the camera focus parameter to be adjusted. Upon selecting the camera focus parameter to be adjusted, the central controller may receive over the communication system the captured camera image of the particular selected IPLD. Upon viewing the captured camera image on the visual display device of the central controller, the operator may next send commands to adjust the focus of the particular IPLD. The operator, using the aid of the visual display device displaying the captured camera images, would use the images to adjust the focus lens  470  of the camera  364 . 
   As the commands are sent to focus the camera, the communications port  311  of the particular IPLD passes the commands to the processor  316 . The processor processes the commands to move the focusing lens a specific number of increments as commanded by the operator of the central controller. The processor  316  and the memory  315  keep track of the focusing value, which is needed to focus the camera lens  468 , in order to obtain the desired focus of the captured camera image of the projection surface  410  of  FIG. 4 . and applies this focus value to the documented relationship residing in the memory  315 . Next, using the documented relationship, the processor updates the projection focus value D 1 F to provide the correct focus of the projected image upon the projection surface  410 . In this way the operator need only adjust the camera to achieve the focus of the projected image created by the main projection lamp optical system. 
   Cameras such as the camera  364  of  FIG. 4  can be equipped with an auto focus system. The auto focus system on many cameras works by using a digital signal processor (usually as part of the onboard electronics) to look at the data of the captured camera image and automatically adjusts the camera focusing lens to achieve the highest amplitude of the high frequency components of the captured image data. Since sharply focused edges of captured camera images are associated with high frequency peaks in the captured image data, the camera focusing lens (such as lens  468  of  FIG. 4 ) is moved by a motor (not shown) by the digital signal processor to achieve the greatest amount of the high frequency components in the captured image data. The techniques of auto focusing cameras are known in the camera art. 
   A camera such as camera  364  of  FIG. 4  having the ability to auto focus may have a communications output (not shown) for communicating focusing values of the focusing lens such as lens  468  of  FIG. 4 . The focusing values may be communicated in digital form from the communications output of the camera. One example of a camera that has a communications output capable of providing focusing values is the FCBEX480A manufactured by Sony (trademarked) Corporation of Tokyo, Japan. The communications output of the camera  363  is connected (wiring not shown for simplification) to the video control interface  317  of  FIG. 3 . 
   The video control interface  317  may be used both to receive captured camera image data and to send and receive control information such as the focusing values of the camera  364 . The video control interface  317  is connected to the processor  316  of  FIG. 3  and the video control interface can send to the processor the camera focusing values. The documented relationship of the camera focusing values, projection focusing values and distances to the projection surface can be stored in the memory  315  of  FIG. 3  as previously explained. 
   In this way when the processor  316  receives a particular camera lens focusing value from the video control interface  317 , this value can be compared to the documented relationship in the memory  315 . The documented relationship in the memory  315  can be used by the processor  316  to send the proper projection focus value control signals to the motor control interface  318  that are used to provide the drive signals to the motor lead screw assembly  376  to move the projection focusing lens  351  to provide the desired focus based upon the camera focusing values. The camera  364  auto focusing system may auto focus both the camera and the projection image to the projection surface. 
   An example of this embodiment can now be described. An operator of the central controller  150  of  FIG. 1  selects a particular IPLD such as IPLD  102  over the communication system by transmitting the correct operating address. Next the operator may command from the central controller  150  a position parameter change and move the lamp housing  230  of  FIG. 2  in relation to the base  210 . As the camera  364  of  FIG. 3  and lamp housing  230  are moved (or positioned) in relation to the base  210 , the projection surface  399  is varied. For example, the lamp housing  230  of  FIG. 2  (and  3 ) and the camera  364  of  FIG. 3  may be directed to point towards a different part of the stage, an audience member or the performer. As the camera  364  and lamp housing  230  are moved in relation to the base  210 , the camera captures the images of the varying projection surfaces and auto focuses on those images so that the captured image of the projection surface will be brought into focus. 
   An autofocus system will send its focusing values from its communication system over wires (not shown) to the video control interface  312  of  FIG. 3 . The video control interface  312  forwards the focusing values to the processor  316 . The processor  316  next compares the camera focusing value with the documented relationship stored in the memory  315  to determine what the projection focus value should be to bring the projected image into focus on the projection surface  399 . Next the processor  316  sends the appropriate signals containing the projection focus values needed to move the projection focusing lens  351  to produce a focused image on the projection surface  399  to the motor control interface  318 . The motor control interface  318  responds by sending the correct motor driving signals to the motor lead screw assembly  376  to incrementally move the projection focusing lens  351  to bring the projected image into focus on the projection surface  399 . In this way, as the lamp housing  230  is moved in relation to the base  210 , and various projection surfaces are captured and auto focused by the camera, focusing values that are produced by the camera are used to affect a change in the projection focusing values, which brings the projected image into focus. 
   When the documented relationship between the camera focusing values and the projection focusing values in the memory  315  have been established, it is also possible for the processor  316  to use the documented relationship in memory  315  to provide control signals to the video control interface  317 , which may be used to provide the necessary camera focusing values to the camera focusing lens to bring the captured camera image into focus based upon the values of the projection focusing lens  351 . There are times when the operator of the central controller  150  of  FIG. 1  may want to first adjust the projection focusing lens  351  of  FIG. 3  of a particular IPLD to bring the projected image into focus on a particular projection surface such as projection surface  410  of  FIG. 4 . 
   In this embodiment, the memory  315  and processor  316  of  FIG. 3  work together to keep track of the values of the projection focusing values as established by the increments sent to the motor lead screw assembly  376  to move the projection focusing lens  351 , and with the use of the documented relationship stored in the memory  315 , use the projection focusing values to calculate the needed camera focusing values so that the camera focusing lens  468  of  FIG. 4  can be brought into focus on the projection surface. 
   In this way, an operator of the central controller  150  of  FIG. 1  need only command the projection focus parameter of a particular IPLD to bring the focus of the projected image into focus on a particular projection surface. The projection focus values are used by the processor  316  of  FIG. 3  to calculate the camera focus values necessary to bring the captured camera image into focus. The camera focus values as derived from the projection focus values are then sent to the video control interface  317  and the video control interface  317  sends the necessary control signals to the camera  364  to bring the camera lens  468  into the required focus to capture the images from particular projection surface. 
   In the event that the camera  364  of  FIG. 3  does not have a communication system that is capable of communicating the focus values to the video control interface  317 , the video image data sent from the camera  364  to the video control interface  317  can be sent to the processor  316  and analyzed to obtain a focus of the projected image on the, projection surface  399 . An operator of the central controller  150  of  FIG. 1  commands an adjustment of the camera focus parameter of a particular IPLD (for example  102  of  FIG. 3 ) of the projection surface  399 . 
   The adjustment of the camera focus may be done by the operator viewing the projection surface on a visual display device located at the central controller  150  of  FIG. 1  and sending adjustment commands for the adjustment of the camera focus from the central controller  150  to the IPLD  102 . Instead the camera  364  may have an auto focus capability that focuses the captured camera image of the projection surface  399 . In either case, with the captured camera image in a desired focus, the image data (which may be a still image or video image) is sent to the video control interface  317  of  FIG. 3 . 
   The video control interface  317  sends the image data to the processor  316  where the image is analyzed for auto focusing techniques. The processor  316  analyzes the image data and incrementally adjusts the position of the projection focusing lens  351  by sending control signals to the motor control interface  318  to incrementally adjust the motor lead screw assembly  376  to move the projection lens  351 . The processor  316  analyzes the image data while moving the projection lens  351  to achieve the highest amplitude of the high frequency components of the captured image data. When the highest amplitude of the captured image data is realized by the processor  316 , the projected image on the projection surface  399  is considered to be in focus and the projection focusing lens  351  is fixed. The various techniques of analyzing image data to achieve an auto focus are known in the auto focusing art. 
   Various combinations of the above embodiment could be used collectively to achieve automatic parameter control in an IPLD. 
   The embodiments set forth herein are merely illustrative and do not limit the scope of the invention or the details therein. It will be appreciated that many other modifications and improvements to the disclosure herein may be made without departing from the scope of the invention or the inventive concepts herein disclosed. Because many varying and different embodiments may be made within the scope of the present inventive concept, including equivalent structures or materials hereafter thought of, and because many modifications may be made in the embodiments herein detailed in accordance with the descriptive requirements of the law, it is to be understood that the details herein are to be interpreted as illustrative and not in a limiting sense.