Abstract:
Described is an animation wheel for an automated luminaire for quick and direct movement between different individual gobos or for positioning anywhere through a plate which substantially exceed the size of the light beam cross-section.

Description:
RELATED APPLICATION 
     This application is a utility filing claiming priority of provisional application 61/316,322 filed on 22 Mar. 2010. 
    
    
     TECHNICAL FIELD OF THE INVENTION 
     The invention relates to equipment for the selection and movement of images or gobos within an automated luminaire. 
     BACKGROUND OF THE INVENTION 
     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 commonly 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. Typically this position control is 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. The beam pattern is often provided by a stencil or slide called a gobo which may be a steel, aluminum or etched glass pattern. The products manufactured by Robe Show Lighting such as the ColorSpot 700E are typical of the art. 
     Such gobos are typically the size of the luminaire&#39;s optical aperture and systems may be provided to select between different gobos, often mounted on a wheel, or to rotate a gobo once selected. The optical systems of such luminaires may further include gobos, patterns or other optical effects which are larger than the optical aperture and may allow movement across or through the beam to produce effects such as rainfall or fire. Such devices are often termed animation wheels and may be included in addition to gobos so as to further modify the light beam. 
       FIG. 1  illustrates a multiparameter automated luminaire system  10 . These systems commonly include a plurality of multiparameter automated luminaires  12  which typically each contain on-board a light source (not shown), light modulation devices, 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 desks  15 . The luminaire system  10  is typically controlled by an operator through the control desk  15 . 
       FIG. 2  illustrates a prior art automated luminaire  12 . A lamp  21  contains a light source  22  which emits light. The light is reflected and controlled by reflector  20  through an aperture or imaging gate  24  and through an animation wheel  25 . The resultant light beam may be further constrained, shaped, colored and filtered by optical devices  26  which may include dichroic color filters, gobos, rotating gobos, framing shutters, effects glass and other optical devices well known in the art. The final output beam may be transmitted through output lenses  28  and  29  which may form a zoom lens system. 
       FIG. 3  illustrates a prior art gobo wheel  1  containing five gobos  3  and an open aperture. The wheel  1  may be rotated  5  such that any of the gobos  3  may be positioned across the optical aperture of the luminaire  4 . 
       FIG. 4  illustrates a further prior art gobo wheel  6 . In this version the gobos  8  are contained within carriers  2  that may be rotated through gears  8 . The wheel may be rotated such that any of the gobo carriers  2  containing a gobo  8  are positioned across the optical aperture of the luminaire  7  and said selected gobo carrier  2  may then be rotated around the optical axis of the luminaire producing a dynamic effect in the output beam. 
     In both examples to change gobos from a first gobo to a second, non-adjacent, gobo requires that the wheel be rotated through all the gobos in between the first and second gobos. It would be advantageous if a gobo system could change from a first gobo to any second gobo without having to pass through intermediate gobos. 
     In addition it would be advantageous if gobos larger than the optical aperture could be inserted and removed from the optical aperture in any position or orientation. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       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: 
         FIG. 1  illustrates a typical automated lighting system; 
         FIG. 2  illustrates a typical automated luminaire; 
         FIG. 3  illustrates a prior art gobo wheel; 
         FIG. 4  illustrates a prior art rotating gobo wheel; 
         FIG. 5  illustrates an embodiment of an animation wheel; 
         FIG. 6  illustrates an alternative embodiment of an animation wheel; 
         FIG. 7  illustrates positions of the embodiment of  FIG. 6 ; 
         FIG. 8  illustrates a further embodiment of the animation wheel of  FIG. 5 ; 
         FIG. 9  illustrates a further embodiment of the animation wheel of  FIG. 6  and  FIG. 7  invention; and 
         FIG. 10  illustrates a further embodiment of the animation wheel of  FIG. 5  and/or  FIG. 8 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     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. 
     The present invention generally relates to an automated luminaire, specifically to the configuration of an animation wheel within such a luminaire such that selection may be made between any two gobos, adjacent or non-adjacent, without the need to pass through intermediate gobos and such that gobos larger than the optical aperture may be utilized. 
       FIG. 5  illustrates a schematic drawing of an embodiment of the invention. Carrier plate  34  contains a gobo wheel  30  which, in turn, carries gobos  32 . Such gobos  32  may be separate gobos individually and separately replaceable on gobo wheel  30  or may be an integral part of wheel  30 . In the embodiment illustrated, gobo wheel  30  has a central aperture  36  which is the same size or larger than the size of a cross section of the light beam  38  at the location of the animation plate  34  along the luminaire&#39;s optical axis. In its normal, resting position as shown in  FIG. 5  gobo wheel aperture  36  is coaxial with cross-section of the light beam  38 . 
     Carrier plate  34  is connected to mounts  41  that include a threaded hole threaded onto threaded rod  43  that may be rotated by motor  46  forming a screw drive. Rotation of motor  46  produces rotation of threaded rod  46 . Since rotation of the mounts  41  is prevented, rotation of the threaded rod  46  results in linear movement  48  of mounts  41  and thus carrier plate  34 . Motor  46  may be rotated in either direction to give complete and accurate control of the position of carrier plate  34  in one plane of motion. 
     Similarly the assembly of motor  46 , rod  48 , mounts  41  and carrier plate  34  is itself mounted to bar  42 . Bar  42  is, in turn, connected to mounts  47  that include a threaded hole threaded onto threaded rod  45  that may be rotated by motor  40  forming a screw drive. Rotation of motor  40  produces rotation of threaded rod  45 . Since rotation of the mounts  47  are prevented, rotation of the threaded rod  48  results in linear movement  44  of mounts  47  and bar  42  with its connected assembly and thus the carrier plate  34 . Motor  40  may be rotated in either direction to give complete and accurate control of the position of carrier plate  34  in a plane of motion orthogonal to that provided by motor  46 . Motors  40  and  46  may be of a type selected from a list comprising but not limited to, stepper motors, servo motors, and linear actuators. 
     Through this mechanism by coordinated and separate adjustment of motors  40  and  46  carrier plate  34  and attached gobo wheel  30  may be positioned such that any of the gobos  32  are positioned across the optical aperture  38 . It can further be seen that as the movement of carrier plate  34  and attached gobo wheel  30  may be in any direction desired it is possible to move directly from a first position where wheel aperture  36  is coaxial with optical aperture  38  to a second position where any of the gobos  32  are across the optical aperture  38  without the need to pass through any other gobos  32 . 
     Further, to move from a first gobo  32  to a second gobo  32  the operator may choose to either move directly to the second gobo without concern for intervening gobos or may choose to first return to the open wheel aperture  36  before continuing to select a second gobo  32 . Thus the operator has complete control over the route taken from a first gobo to a second gobo. 
     The specific mechanism illustrated herein using two threaded rods and threaded mounts is illustrative only and not a limitation of the invention. Other mechanisms well known in the art to move carrier plate  34  in two orthogonal directions may be used without departing from the spirit of the invention. In alternative embodiments the orientation of the drives may not be orthogonal. What is important is that the drives provides two degrees of freedom of motion to position the carrier plate anywhere within the confines of a constrained two-dimensional plane. 
       FIG. 6  illustrates a schematic drawing of an embodiment of the invention. In this embodiment the movement of carrier plate  34  in two orthogonal directions is as described for  FIG. 5 . However instead of repositioning a gobo wheel with individual discrete gobos  32  gobo wheel  30  contains a single large gobo, pattern or effect  37 . Through this mechanism by coordinated and separate adjustment of motors  40  and  46  carrier plate  34  and attached gobo wheel  30  may be positioned such that any portion of the gobo  37  may be positioned across the optical aperture  38 . Gobo  37  may comprise a single large pattern or optical effect or may contain multiple individual images. 
     A further advantage of the invention is the speed with which any gobo or a portion of a gobo may be selected. As selection can always move directly from a first current position to a second target position no movement is wasted and minimum length moves, and thus minimum time moves, are possible. 
       FIGS. 7   a  and  7   b  further illustrate an embodiment of the invention and show two possible positions for the mechanism. In  FIG. 7   a  motor  46  has positioned carrier plate  34  as far to the left as possible while motor  40  has positioned carrier plate in a mid position vertically. This results in the central right portion of gobo  37  being positioned across optical aperture  38 .  FIG. 7   b  illustrates a second position where both motors  40  and  46  have repositioned carrier plate  34  such that a lower left portion of gobo  37  is positioned across optical aperture  38 . It is clear that through manipulation of motors  40  and  46  any portion of gobo  37  may be positioned across optical aperture  38 . 
       FIG. 8  illustrates a schematic drawing of an embodiment of the invention. The mechanism as illustrated in  FIG. 5  has been augmented with a third motor  50 . Motor  50  is mounted to carrier plate  34  and moved with carrier plate  34 . The rotation of the output shaft of motor  50  is coupled to gobo wheel  30  so as to allow rotation  52  of gobo wheel  30  around the axis of its central aperture  36 . This rotation of gobo wheel  30  can be utilized in a number of ways. Firstly it could be used to simulate a prior art gobo wheel where rotation of the wheel positions all gobos in turn across optical aperture  38 . Alternatively it can be used with a single large gobo as shown in  FIGS. 6 ,  7   a  &amp;  7   b  to move a single large image across the optical aperture to provide movement or effects such as rain or fire. 
     In a yet further embodiment as illustrated in  FIG. 9 , gobo wheel  30  may comprise a single piece of optical filter glass with, for example, lenticular lens pattern or prisms. Rotation of such a wheel by motor  50  will cause a rotation of the optical effect caused by the optical filter glass. 
     In alternative embodiments of systems such as that illustrated in  FIG. 8 , motor  50  drives the rotation of the gobos rather than the wheel  30 . I this way the affects wheel can be positioned to place a gobo  32  in the path cross-section  38  and then the gobo  32  rotates causing the projected image to be rotated. 
     In alternative embodiments the gobo wheel need not be round and may not have a central aperture or any aperture. 
       FIG. 10  illustrates a further embodiment of the invention. The mechanism is similar to that shown and described in  FIG. 5  however gobo wheel  30  contains two concentric rings of gobos  32 . In this embodiment the frame  34  may be moved through rotation of motors  40  and  46  such that any individual gobo  32  is positioned across aperture  38 . Although two rings of gobos are illustrated the invention is not so limited and any number of arrangement of gobos  32  may be positioned on gobo wheel  30  such that individual gobos  32  may be positioned across aperture  38 . Such gobos  32  may be of differing sizes and orientations. 
     While the invention has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this invention, will appreciate that other embodiments may be devised which do not depart from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be limited only by the attached claims. 
     The invention 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 invention as described by the appended claims.