Abstract:
Disclosed is an LED light source automated luminaire with a multi sided elongated light collimator/mixer/integrator with receiving lens and output lens both with spill shields and where the receiving spill shield is nesting in the output spill shield. The elongated integrator has a square input cross-section and a hexagon or octagon output cross section and is tapered so that the input cross section is smaller than the output cross section.

Description:
RELATED APPLICATION 
       [0001]    The present application claims priority of:
       PCT/US15/53557 international application filed 1 Oct. 2015 claiming, 62/058,566 provisional application filed 1 Oct. 2014; and   PCT/US14/58682 international application filed 1 Oct. 2014 claiming, 61/885,003 provisional application filed 1 Oct. 2013.       
 
     
    
     TECHNICAL FIELD OF THE INVENTION 
       [0004]    The present invention generally relates to a method for controlling the light output from an array of LEDs when used in a light beam producing luminaire, specifically to a method relating to improving the homogenization and collimation of the LEDs and for controlling the beam angle of the array. 
       BACKGROUND OF THE INVENTION 
       [0005]    Luminaires with automated and remotely controllable functionality are well known in the entertainment and architectural lighting markets. Such products are commonly used in theatres, television studios, concerts, theme parks, night clubs and other venues. A typical product will typically provide control over the pan and tilt functions of the luminaire allowing the operator to control the direction the luminaire is pointing and thus the position of the light beam on the stage or in the studio. This position control is often done via control of the luminaire&#39;s position in two orthogonal rotational axes usually referred to as pan and tilt. Many products provide control over other parameters such as the intensity, color, focus, beam size, beam shape and beam pattern. Additionally it is becoming common to utilize high power LEDs as the light source in such luminaires and, for color control, it is common to use an array of LEDs of different colors. For example a common configuration is to use a mix of Red, Green and Blue LEDs. This configuration allows the user to create the color they desire by mixing appropriate levels of the three colors. For example illuminating the Red and Green LEDs while leaving the Blue extinguished will result in an output that appears Yellow. Similarly Red and Blue will result in Magenta and Blue and Green will result in Cyan. By judicious control of the LED controls the user may achieve any color they desire within the color gamut set by the LED colors in the array. More than three colors may also be used and it is well known to add an Amber or White LED to the Red, Green and Blue to enhance the color mixing and improve the gamut of colors available. The products manufactured by Robe Show Lighting such as the Robin 600 LEDWash are typical of the art. 
         [0006]    The differently colored LED dies may be arranged on packages in the luminaire such that there is physical separation between each color of LED, and this separation, coupled with differences in die size for each color, may affect the spread of the individual colors and results in inadequate mixing of the different colors along with objectionable spill light and color fringing of the combined mixed color output beam. It is common to use a lens or other optical device in front of each LED package to control the beam shape and angle of the output beam; however these optical devices may have differing effect for different colors and color fringing or other aberrations may be visible in the output beam. It would be advantageous to have a system where stray light and aberrations are well controlled. 
         [0007]      FIG. 1  illustrates a prior art system showing two LEDs in a package as may be used in a luminaire. LED  2  and LED  4  may be of differing colors and, due to the different optical properties and construction of the LED dies  2 ,  4  produce light beams  6  and  8  that differ in beam spread. The differing beam spreads mean that the light beams from LEDs  2  and  4  will impinge on an illuminated object  18  in such a way that areas  20  and  16  of the object are illuminated by a single LED only rather than the desired mix of both. This results in areas  120  and  16  being colored differently from the central mixed area and appearing as colored fringes. Only Two (2) LEDs are illustrated in  FIG. 1  for clarity and simplicity. It should be appreciated that the same problem exists with systems incorporating more than two colors of LED. 
         [0008]      FIG. 2  illustrates a typical multiparameter automated LED luminaire system  10 . These systems commonly include a plurality of multiparameter automated luminaires  12  which typically each contain on-board an array of LEDs, and electric motors coupled to mechanical drives systems and control electronics (not shown). In addition to being connected to mains power either directly or through a power distribution system (not shown), each luminaire is connected is series or in parallel to data link  14  to one or more control desk(s)  15 . The luminaire system  10  is typically controlled by an operator through the control desk  15 . Consequently, to affect this control, both the control desk  10  and the individual luminaires typically include electronic circuitry as part of the electromechanical control system for controlling the automated lighting parameters. 
         [0009]      FIG. 3  and  FIG. 4  illustrate an optical system used in the prior art to provide a variable beam angle or zoom to an automated LED luminaire. Each LED  50  which may be fitted with a primary optic  52  has an associated pair of lenses  53  and  55 . Lenses  53  and  55  may be separate lenses or each part of an array of lenses covering the entire LED array. Lenses  53  and  55  may each comprise a single optical element  56  and  57  respectively. In operation at least one of lens  53  or lens  55  is stationary with respect to LED  50  while the other may move along optical axis  59 . In the example illustrated in  FIGS. 3 and 4  lens  55  is fixed relative to LED  50  while lens  53  is able to move along optical axis  59 .  FIG. 3  shows lens  53  in a first position and  FIG. 4  shows lens  53  in a second position closer to LED  50 . This varying relative position between LED  50 , lens  53  and lens  55  provides a beam angle or zoom to the light beam from LED  50 . Such systems are often limited in their zoom range by optical problems caused by the color separation and inadequate beam homogenization. They may further be limited by requiring large movements of the lenses. 
         [0010]    This is a need for an optical system for an LED automated luminaire which provides improved color homogenization and beam collimation while also providing improved zoom range. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    For a more complete understanding of the present invention and the advantages thereof, reference is now made to the following description taken in conjunction with the accompanying drawings in which like reference numerals indicate like features and wherein: 
           [0012]      FIG. 1  illustrates a prior art LED lighting system; 
           [0013]      FIG. 2  illustrates a typical automated lighting system; 
           [0014]      FIG. 3  illustrates optical components of a prior art LED luminaire; 
           [0015]      FIG. 4  illustrates optical components of a prior art LED luminaire; 
           [0016]      FIG. 5  illustrates optical components of an embodiment of the LED luminaire; 
           [0017]      FIG. 6  illustrates a front view of the collimating and mixing optic  80  and LED  60  of  FIG. 5 ; 
           [0018]      FIG. 7  illustrates a front view of the light integrator  102  of  FIG. 5 ; 
           [0019]      FIG. 8  illustrates a further embodiment of the embodiment illustrated in  FIG. 5 ; 
           [0020]      FIG. 9  illustrates an alternative embodiment of the LED luminaire; 
           [0021]      FIG. 10  illustrates a front view of the collimating and mixing optic  80  and LED  60  of  FIG. 5 ; 
           [0022]      FIG. 11  illustrates a front view of the light integrator  102  of  FIG. 5 ; 
           [0023]      FIG. 12  illustrates a further embodiment of the embodiment illustrated in  FIG. 5 ; 
           [0024]      FIG. 13  illustrates an alternative embodiment of the LED luminaire illustrated in  FIG. 5 ; 
           [0025]      FIG. 14  illustrates an alternative embodiment of the LED luminaire illustrated in  FIG. 9 ; 
           [0026]      FIG. 15  illustrates an alternative embodiment of the LED luminaire with light spill reducing element; 
           [0027]      FIG. 16  illustrates an alternative embodiment of an optical element; 
           [0028]      FIG. 17  illustrates an alternative embodiment of the optical element; 
           [0029]      FIG. 18  illustrates an embodiment of the light integrator; 
           [0030]      FIG. 19  illustrates an alternative embodiment of the light integrator; 
           [0031]      FIG. 20  illustrates an embodiment of the light integrator fitted with a gobo or pattern wheel; 
           [0032]      FIG. 21  illustrates an alternative embodiment of the light integrator fitted with a gobo or pattern wheel; 
           [0033]      FIG. 22  illustrates an alternative embodiment of the light integrator fitted with a gobo or pattern wheel; 
           [0034]      FIG. 23  illustrates an embodiment of the light integrator fitted with a gobo or pattern wheel; 
           [0035]      FIG. 24  illustrates an embodiment of the light integrator fitted with a static gobo or pattern wheel and a rotating gobo or pattern wheel; 
           [0036]      FIG. 25  illustrates an example of a full static gobo wheel; 
           [0037]      FIG. 26  illustrates an example of a full rotating gobo wheel; 
           [0038]      FIG. 27  illustrates an alternative example of a full static gobo wheel; 
           [0039]      FIG. 28  illustrates an example of a partial static gobo wheel; 
           [0040]      FIG. 29  illustrates an embodiment of an array of light integrators of the invention, each fitted with a partial gobo wheel; 
           [0041]      FIG. 30  illustrates an alternative embodiment of the light integrator fitted with a static gobo or pattern wheel and a rotating gobo or pattern wheel; and; 
           [0042]      FIG. 31  illustrates an alternative embodiment of the light integrator fitted with a static gobo or pattern wheel and a rotating gobo or pattern wheel. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0043]    Preferred embodiments of the present invention are illustrated in the FIGUREs, like numerals being used to refer to like and corresponding parts of the various drawings. 
         [0044]    The present invention generally relates to a method for controlling the light output from an array of LEDs when used in a light beam producing luminaire, specifically to a method relating to improving the homogenization and collimation of the LEDs and for controlling the beam angle of the array. 
         [0045]      FIG. 5  illustrates an embodiment of the optical system of the invention. LED  60 , which may include a primary optic, is mounted on substrate  62 . LED  60  may contain a single color die or may contain multiple dies, each of which may be of differing colors. The light output from the dies in LED  60  enters collimating and mixing optic  80  at light entry port  82 . Collimating and mixing optic  80  may be a solid optic using total internal reflection (TIR) to direct the light or may be a hollow reflective surface. Collimating and mixing optic  80  may have four sides  86 , each of which may be curved with cornered sides  92 . The end view of collimating and mixing optic  80  in  FIG. 6  combined with side illustration of the collimating and mixing optic  80  in  FIG. 5  illustrate details an embodiment of the shape. The combination square sided shape with curved sides provides excellent mixing of the light from the dies  64  in LED  60 . A further feature of collimating and mixing optic  64  is that it directs the reflected light to an external focal point which is comparatively close to its output port  84  of the collimating and mixing optic  80 . 
         [0046]    In the embodiments illustrated in  FIG. 6  the configuration of the plurality of LED dies  64  in LED  60  is square and aligned with the sides  86  of the collimator  80 . In other embodiments the alignment of the dies with the collimator sides may not be aligned, for example as illustrated in  FIG. 10 . In alternative embodiments of those illustrated in  FIG. 6  and  FIG. 10  the collimator may have a plurality of slides of three four or more sides. In further embodiments the arraignment of the dies in the LED array may be configured in different shapes and paired with collimators with matching or divergent shapes. 
         [0047]    In different embodiments degree of curvature of the sides  86  may vary—flatter for some configurations and more curved for other configurations. Additionally, the sharpness of the corners  92  between the sides may vary among different collimators—sharper for some configurations and rounder for others. The selection of the number of sides and the curvature of the sides and curvature of the corners is/are tradeoffs between the degree of mixing desired and acceptable light loss for a particular configuration or application. 
         [0048]    In the embodiment shown in  FIG. 5 , the reflected light exits collimating and mixing optic  64  at port  84  and enters light integrator optic  102  at its entry port  106 . Light integrator  102  is a device utilizing internal reflection so as to collect, homogenize and constrain and conduct the light from collimating and mixing optic  80 . Light integrator  102  may be a hollow tube with a reflective inner surface such that light impinging into the entry port may be reflected multiple times along the tube before leaving at the exit port  108 . Light integrator  102  may be a square tube, a hexagonal tube, a heptagonal tube, an octagonal tube, a circular tube, or a tube of any other cross section. In a further embodiment light integrator  102  may be a solid rod constructed of glass, transparent plastic or other optically transparent material where the reflection of the incident light beam within the rod is due to total internal reflection (TIR) from the interface between the material of the rod and the surrounding air. The integrating rod may a square rod, a hexagonal rod, a heptagonal rod, an octagonal rod, a circular rod, or a rod of any other cross section. Integrator embodiments with a polygonal cross section have reflective sides  110  and corners  112  between the reflective sides as seen in  FIG. 5  which includes a side cross sectional view of the integrator  102  and more easily seen in  FIG. 7  a front exit port view of the integrator  102 . 
         [0049]    In a yet further embodiment the light integrator  102  may have a straight sided square cross section at the entrance port and a straight sided polygonal cross section with more than four sides at the exit port. The exit port may be pentagonal, hexagonal, heptagonal, octagonal, or have any other integral number of sides. 
         [0050]    A feature of a light integrator  102  which comprises a hollow or tube or solid rod where the sides of the rod or tube are essentially parallel and the entrance aperture  106  and exit aperture  108  are of the same size is that the divergence angle of light exiting the integrator  102  at exit port  108  will be the same as the divergence angle for light entering the integrator  102  at entry port  106 . Thus a parallel sided integrator  102  has no effect on the beam divergence and will transfer the position of the focal point of collimating and mixing optic  80  at its exit aperture  84  to the integrator&#39;s  102  exit aperture  108 . The light exiting integrator  102  will be well homogenized with all the colors of LED  60  mixed together into a single colored light beam and may be used as our output, or may be further modified by downstream optical systems. 
         [0051]    Integrator  102  may advantageously have an aspect ratio where its length is much greater than its diameter. The greater the ratio between length and diameter, the better the resultant mixing and homogenization will be. Integrator  66  may be enclosed in a tube or sleeve  104  which provides mechanical protection against damage, scratches, and dust. 
         [0052]      FIG. 8  illustrates a further embodiment of the invention. Elements LED  60 , substrate  62 , collimating and mixing optic  80 , integrator  102 , are as described above for  FIG. 5 ,  FIG. 6  and  FIG. 7 . In this embodiment the homogenized and focused light exiting from integrator  66  is directed through lens system  120  and  122 . Lenses  120  and  122  may be independently movable  124  and  126  along the optical axis so as to provide beam angle control over the light beam. Because the focal point of collimating and mixing optic  80  is short, a small motion of lenses  120  and  122  may cause a large change in beam angle. In one embodiment movements  124   126  of 10 mm in the position of lenses  120  and/or  122  may cause a change in beam angle from 5° to 50°. Thus providing an improved variable beam angle or zoom to an automated LED luminaire. 
         [0053]    In further embodiments, lenses  120  and  122  may form an achromatic optical system such that it provides the same degree of beam angle change to long wavelength red light as it does to short wavelength blue light and thus avoids chromatic aberration. This ensures that the beams from the different colors of LED dies  64  in LED  60  are all the same size resulting in a uniformly colored combined beam. In yet further embodiments any number of lenses may be used as the lens system. In all cases, lenses may contain one or more optical elements. Lenses  120  and  122  are illustrated herein as bi-convex lenses however the invention is not so limited and lenses  120  and  122  may be any shaped optical element as well known in the art. 
         [0054]      FIG. 9  illustrates an embodiment of the optical system of the invention. LED  60 , which may include a primary optic, is mounted on substrate  62 . LED  60  may contain a single color die  64  or may contain multiple dies  64 , each of which may be of differing colors. The light output from the dies  64  in LED  60  enters light integrator optic  102  at entry port  106 . Light integrator  102  may be of the same construction and configuration as in the embodiment illustrated in  FIG. 5 . Light integrator  102  is a device utilizing internal reflection so as to collect, homogenize and constrain and conduct the light to the entry port  82  of collimating and mixing optic  80 . Light integrator  102  may be a hollow tube with a reflective inner surface such that light impinging into the entry port  106  may be reflected multiple times along the tube before leaving at the exit port  108 . Light integrator  102  may be a square tube, a hexagonal tube, a heptagonal tube, an octagonal tube, a circular tube, or a tube of any other cross section. In a further embodiment light integrator  102  may be a solid rod constructed of glass, transparent plastic or other optically transparent material where the reflection of the incident light beam within the rod is due to total internal reflection (TIR) from the interface between the material of the rod and the surrounding air. The integrating rod may a square rod, a hexagonal rod, a heptagonal rod, an octagonal rod, a circular rod, or a rod of any other cross section. 
         [0055]    A feature of a light integrator  102  which comprises a hollow or tube or solid rod where the sides of the rod or tube are essentially parallel and the entrance aperture  106  and exit aperture  108  are of the same size is that the divergence angle of light exiting the integrator  102  exit port  108  will be the same as the divergence angle for light entering the integrator  102  at entry port  106  from LED  60 . Thus a parallel sided integrator  102  has no effect on the beam divergence and will transfer the light from LED  60  to its exit aperture  108 . The light exiting integrator  102  will be well homogenized with all the colors of LED  60  mixed together into a single colored light beam. 
         [0056]    Integrator  102  may advantageously have an aspect ratio where its length is much greater than its diameter. The greater the ratio between length and diameter, the better the resultant mixing and homogenization will be. Integrator  102  may be enclosed in a tube or sleeve  104  which provides mechanical protection against damage, scratches, and dust. 
         [0057]    Light exiting integrator  102  at exit port  108  enters collimating and mixing optic  80  at its entry port  82 . Collimating and mixing optic  80  may be of the same construction and configuration as the collimating and mixing optic in embodiment illustrated in  FIG. 5 . Collimating and mixing optic  80  may be a solid optic using total internal reflection (TIR) to direct the light or may be a hollow reflective surface. Collimating and mixing optic  80  may have four sides, each of which may be curved. The side view of collimating and mixing optic  80  included in  FIG. 9  and the end view of collimating and mixing optic  80  in  FIG. 10  illustrate the detail of this shape. The combination square sided shape with curved sides provides further mixing of the light from the dies in LED  60  as homogenized by integrator  102 . A further feature of collimating and mixing optic  80  is that it directs the reflected light to an external focal point which is comparatively close to its output face. 
         [0058]    In the embodiment shown in  FIG. 9  the reflected light exits collimating and mixing optic  80  at exit port  84  and may be used as our output, or may be further modified by downstream optical systems. 
         [0059]      FIG. 8  illustrates a further embodiment of the invention. Elements LED  60 , substrate  62 , collimating and mixing optic  80 , integrator  102 , can be as described above. In this embodiment the homogenized and focused light exiting from collimating and mixing optic  64  is directed through lens system  120  and  122 . Lenses  120  and  122  may be independently movable along the optical axis so as to provide beam angle control over the exiting light beam. Because the focal point of collimating and mixing optic  80  is short, a small motion of lenses  120  and  122  may cause a large change in beam angle. In one embodiment a movement of 10 mm in the position of lenses  120  and/or  122  may cause a change in beam angle from 5° to 50°. Thus providing an improved variable beam angle or zoom to an automated LED luminaire. 
         [0060]    In further embodiments, lenses  120  and  122  may form an achromatic optical system such that it provides the same degree of beam angle change to long wavelength red light as it does to short wavelength blue light and thus avoids chromatic aberration. This ensures that the beams from the different colors of LED dies in LED  60  are all the same size resulting in a uniformly colored combined beam. In yet further embodiments any number of lenses may be used as the lens system. In all cases, lenses may contain one or more optical elements. Lenses  120  and  122  are illustrated herein as bi-convex lenses however the invention is not so limited and lenses  120  and  122  may be any shaped optical element as well known in the art and may include any number of lenses including a single lens. This applies to any of the embodiments discussed above 
         [0061]      FIG. 13  and  FIG. 14  illustrate further alternative embodiments of LED luminaires. In both of these embodiments the light integrator  102 , whether solid or hollow, has sides  110  which are tapered so that entrance aperture  106  is smaller than the exit aperture  108 . The advantage of this structure is that the divergence angle of light exiting the integrator  102  at exit port  108  will be smaller than the divergence angle for light entering the integrator  102  at entry port  106 . The combination of a smaller divergence angle from a larger aperture serves to conserve the etendue of the system. Thus a tapered integrator  102  may provide similar functionality to a condensing optical system. Therefore some embodiments may not include optical elements  120   122  as discussed above while other embodiments may include such elements as discussed above with regard to embodiments with non-tapered integrators. 
         [0062]      FIG. 15  illustrates a further alternative embodiment of LED luminaires. In this embodiment the light integrator  102 , whether solid or hollow, and with any number of sides, or with a square entry port  106  and a polygonal exit port  108  has sides  110  which are tapered so that entrance aperture  106  is smaller than the exit aperture  108 . The advantage of this structure is that the divergence angle of light exiting the integrator  102  at exit port  108  will be smaller than the divergence angle for light entering the integrator  102  at entry port  106 . The combination of a smaller divergence angle from a larger aperture serves to conserve the etendue of the system. Thus a tapered integrator  102  may provide similar functionality to a condensing optical system. Therefore some embodiments may not include optical elements  120   122  as discussed above while other embodiments may include such elements as discussed above with regard to embodiments with non-tapered integrators. Additionally this embodiment may alternately utilize lenses  130  and  132  as optical elements providing condensing, beam angle control, and focusing functionality as described above as a replacement for the collimating and mixing optic used in earlier embodiments. Lenses  130  and  132  may be meniscus lenses, plano convex lenses, bi-convex lenses, or other lenses as well known in the art. In the embodiment illustrated lens  130  is a plano-convex lens, and lens  132  is a meniscus lens. 
         [0063]      FIG. 15  also shows optional spill reducing elements  131  and  133 . Spill reducing elements  131  and  133  may comprise hollow opaque thin walled tubes which are attached to, and move with, optical elements  130  and  132  respectively. These tubes reduce light spill from the exit port  108  which may impinge on adjacent light integrators and their associated optical systems. Spill reducing element  131  may be of a smaller diameter than spill reducing element  133  such that optical element  130  and its attached spill reducing element  131  may move within spill reducing element  133  such that optical elements  130  and  132  may move to be adjacent. An external further additional spill reducing element  135  may also be added to and may move with lens  132 . Lenses  130  may be moved as shown by arrow  134 , and lens  132  may be moved as shown by arrow  136 . Such movement allows changing the focal length, and thus the beam angle of the output light beam. Lenses  130  and  132  may move together as a pair with a single actuator, or, in a further embodiment, may move independently each with its own actuator. 
         [0064]      FIG. 16  shows an alternative embodiment of the layout of the front optical elements of the system. In, for example  FIG. 15 , there is a front optical element  132  which forms the final output lens of the system.  FIG. 16  shows a front view of four of the systems  204  shown in  FIG. 15  mounted in a square array. In this embodiment the four optical elements  162 ,  164 ,  166 , and  168  in  FIG. 16  each represent an identical example of element  132  in  FIG. 15 . Optical element  162  is constructed as part of a larger, quadrant shaped, structure  172 . Structure  172  incorporating optical element  162  may be molded from a single piece of glass or optical plastic. Similarly optical element  164  is incorporated as part of quadrant  174 , optical element  166  is incorporated as part of quadrant  176 , and optical element  168  is incorporated as part of quadrant  178 . The incorporation of the optical elements in to quadrants provides two desirable results. Firstly, four modules may be placed in a square array while representing an unbroken and clean appearance from the front with the four quadrants joining to provide a complete circle. Secondly, any remaining spill light from the optical modules will disperse and dissipate within the areas of the quadrants outside the optical elements, providing an attractive light glow between the optical elements. 
         [0065]      FIG. 17  shows a further alternative embodiment of the layout of the front optical elements of the system. In, for example  FIG. 15 , there is a front optical element  132  which forms the final output lens of the system.  FIG. 16  shows a front view of four of the systems  204  shown in  FIG. 15  mounted in a square array. In this embodiment the four optical elements  182 ,  184 ,  186 , and  188  in  FIG. 17  each represent an identical example of element  132  in  FIG. 15  molded into a quadrant shape. The configuration of the optical elements as quadrants provides two desirable results. Firstly, four modules may be placed in a square array while representing an unbroken and clean appearance from the front with the four quadrants joining to provide a complete circle. Secondly, any remaining spill light from the optical modules will disperse and dissipate within the areas of the quadrants outside the optical elements, providing an attractive light glow between the optical elements. 
         [0066]      FIG. 18  illustrates an embodiment of the light integrator  104   a  of the invention. In this embodiment entrance port  106   a  is square in cross-section and exit port  108   a  is hexagonal in cross-section. 
         [0067]      FIG. 19  illustrates an alternative embodiment of the light integrator  104   b  of the invention. In this embodiment entrance port  106   b  is square in cross-section and exit port  108   b  is octagonal in cross-section. 
         [0068]    In the alternative embodiments illustrated in  FIGS. 20, 21, 22, and 23  the optical system is further fitted with a gobo wheel system  150 . A gobo wheel contains patterns or images that will controllably mask the light exiting through port  84 . These images will then be projected by downstream optical elements to create a pattern projecting light beam. The lens system after the gobo wheel may be a zoom lens system  120  and  122  such as shown in  FIG. 20  or any other projecting lens system as well known in the art. Gobo wheel  154  may be rotated through motor  152  and shaft  153  in order to select different gobo patterns in front of exit aperture  84 . Gobo wheel system  150  may incorporate a static gobo wheel, a rotating gobo wheel, or both. The static gobo wheel or rotating gobo wheel may each be a full wheel, or a partial wheel. 
         [0069]      FIG. 24  illustrates both a full static gobo wheel and a full rotating gobo wheel as fitted to an embodiment of the invention. Gobo wheel  163  may be rotated through motor  164  in order to select different gobo patterns in front of exit aperture  108 . In yet further embodiments individual gobo patterns may be further rotated about their axes by supplementary motors in order to provide a moving rotating image. Such rotating gobo wheels are well known in the art. Rotating gobo wheel,  165 , is an example of such an embodiment. Rotating gobo wheel  165  may be rotated through motor  166  in order to select different gobo patterns  168  in front of exit aperture  108 . Gobo patterns  168  may then be rotated about the optical axis of the system through motor  167 . 
         [0070]      FIG. 25  shows gobo wheel  163  in more detail in a further embodiment of the invention. Gobo wheel  163  contains a plurality of patterns including, for example,  172 ,  173 ,  174 ,  176 , and  178  that may be moved across and in front of the exit port of the light integrator by rotation about motor  164 .  FIG. 26  shows rotating gobo wheel  165  in more detail in a further embodiment of the invention. Gobo wheel  165  contains a plurality of patterns including, for example,  182  that may be moved across and in front of the exit port of the light integrator by rotation about motor  166 . These gobo patterns may then be rotated about the optical axis of the system through motor  167 .  FIG. 27  shows gobo wheel  150  in more detail in a further embodiment of the invention. Gobo wheel  150  contains a plurality of patterns including, for example,  172 ,  173 ,  174 ,  176 , and  178  that may be moved across and in front of the exit port of the light integrator by rotation about motor  164 . 
         [0071]    In further embodiments the gobo wheel may not be a complete circular disc as shown in  FIG. 27 , but may be a portion of a disc, or a flag so as to save space and provide a more limited number of gobo options.  FIG. 28  illustrates an embodiment of a partial gobo wheel where gobo wheel  154  is a quadrant of a circle containing three gobos,  182 ,  184 , and  186 . Such an arrangement with a partial wheel facilitates embodiments such as that illustrated in  FIG. 29  where multiple light integrators are utilized in a single luminaire. Each of those light integrators may be fitted with an independent gobo system  150 , all or any of which may be individually or cooperatively controlled. Utilizing partial wheels  154  may allow a tighter packing density for the light integrators and optical systems without interference between the adjacent wheels. In the example illustrated nine light integrators and associated gobo systems  150  are utilized in a circular arrangement. However, the invention is not so limited and any number of light integrators in any arrangement may be utilized without departing from the spirit of the invention. Additionally, it is not necessary that every light integrator is fitted with a gobo system; embodiments may be constructed where a proportion of the light integrators is fitted with gobo systems, and a proportion is not. 
         [0072]      FIG. 30  illustrates both a full static gobo wheel and a full rotating gobo wheel as fitted as gobo system  150  to an alternative embodiment of the invention. Gobo wheel  163  may be rotated through motor  164  in order to select different gobo patterns in front of exit aperture  84 . In yet further embodiments individual gobo patterns may be further rotated about their axes by supplementary motors in order to provide a moving rotating image. Such rotating gobo wheels are well known in the art. Rotating gobo wheel,  165 , is an example of such an embodiment. Rotating gobo wheel  165  may be rotated through motor  166  in order to select different gobo patterns  168  in front of exit aperture  108 . Gobo patterns  168  may then be rotated about the optical axis of the system through motor  167 . 
         [0073]      FIG. 31  illustrates both a full static gobo wheel and a full rotating gobo wheel as fitted as gobo system  150  to a preferred embodiment of the invention. Gobo wheel  163  may be rotated through motor  164  in order to select different gobo patterns in front of exit aperture  108 . In yet further embodiments individual gobo patterns may be further rotated about their axes by supplementary motors in order to provide a moving rotating image. Such rotating gobo wheels are well known in the art. Rotating gobo wheel,  165 , is an example of such an embodiment. Rotating gobo wheel  165  may be rotated through motor  166  in order to select different gobo patterns  168  in front of exit aperture  108 . Gobo patterns  168  may then be rotated about the optical axis of the system through motor  167 . 
         [0074]    In all embodiments both the static and rotating gobo patterns may be of any shape and may include colored images or transparencies. Additionally effects such as prisms, lenticular lenses, or break up glasses may be used without departing from the spirit of the invention. Fort example, the use of a lenticular lens may provide an elliptical beam from each light integrator and rotating that lenticular lens may rotate the elliptical beam about its optical axis. Cooperatively or independently rotating such lenticular lenses on a luminaire with multiple light integrators such as that illustrated in  FIG. 29 , may provide new dynamic lighting effects for the operator. 
         [0075]    While the disclosure has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments may be devised which do not depart from the scope of the disclosure as disclosed herein. The disclosure has been described in detail, it should be understood that various changes, substitutions and alterations can be made hereto without departing from the spirit and scope of the disclosure.