Abstract:
A compact projector system utilizing a rear projection console with at least one projector and a set of mirrors with each mirror being positionally placed with respect to the rear of the display screen and operating together by bouncing an image carrying light beam which originates from a projector from one mirror to the next within the console and across itself before the image-carrying light impinges upon the rear of the display screen to produce a relatively large, contiguous image thereupon with the at least one projector and set of mirrors being confined in a relatively small console area.

Description:
FIELD OF THE INVENTION 
     The present invention pertains to projection systems, and more specifically, to a rear projection console with at least one image-carrying light beam that reflects upon a unique layout of mirrors before impinging upon the rear of the display screen to produce a relatively large, contiguous image thereupon. 
     BACKGROUND OF THE INVENTION 
     The use of mirrors to change the direction of a light beam carrying an image is a common practice in rear projection devices. Typically, a light source will bounce from one mirror to another and so on until the light reaches the rear side of a display screen contained within a cabinet, where the image contained within the light will be projected thereon. Traditionally however, these types of mirrors have been fixed, preventing a user from adjusting the image projected to a desired place on the rear projection screen. Typically, the image that is projected is of a single size, even though it may be desirous to enlarge or shrink the image size. Also, in very large applications where an image or images are projected onto a plurality of screens, a seam can appear where image boundaries meet, thereby producing a non-contiguous image. 
     One of the more difficult design problems in rear projection imagers is the placement of mirrors to optimize limited console space. Many different configurations have been disclosed that reflect images in different ways inside of cabinets, with the initial beam of light being bounced off of at least one mirror in various dispositions. The present invention address the difficulty of limited cabinet space by teaching the projection of an image onto one mirror situated at an oblique angle to the screen, from there onto another mirror positioned at an acute angle with the screen, and finally on through itself to the projection screen. This particular arrangement of mirrors which causes the light to pass through itself without significant degradation of image quality, uses the limited console space in an efficient manner to reduce the actual space required to project an image onto a rear projection screen. 
     Traditionally in rear projection systems, the mirrors used to reflect a light with an image contained therein have been securably mounted within the rear projection cabinet. By rigidly securing the mirrors within the cabinet, a user is unable to position the image on the screen as desired through mirror manipulation. While this is perhaps a minor inconvenience in a home viewing environment, in applications such as the present invention where multiple projectors can be linked to produce a contiguous image, the inability to shift image position upon the rear projection screen using mirror manipulation is a problem. The present invention facilitates the need for image stability by making the image projector and the mirrors fixedly mounted within the console, yet facilitates the need for image adjustment by allowing alignment adjustment to occur at the second mirror. 
     In the present invention, the second mirror can also be replaced by either a convex or concave mirror to magnify or reduce the image size as it appears on the display screen. While the use of irregularly shaped mirrors to distort light waves is not new, their use in that manner in combination with a light beam crossing over itself is. In practical application, the irregularly shaped mirrors will allow a sized image on the projection screen otherwise not possible with the limited volume of the console. 
     In one embodiment of the invention the imager, the mirrors and the display screen rigidly mounted to minimize relative movements between the units thereby minimizing the likelihood of relative movements between the units. In another embodiment the units while rigidly mounted can be made postionable to enable an operator to fine tune the position of the images on the display screen. 
     Therefore, it is a purpose of this invention to create a compact projection system with an imager that projects an imager-carrying light through a configuration of mirrors and through itself before impinging on the rear of a display screen. 
     It is a further purpose of this invention to create a projection system that operates in a confined area, or an area of limited space. 
     It is a further purpose of this invention to create a projection system that can interlock with at least one other projection system of like construct to produce a seamless, contiguous image on a display screen. 
     It is still another purpose of this invention to create a projection system with mirrors that can be irregularly shaped to produce a magnified or reduced image upon a display screen. 
     DESCRIPTION OF THE PRIOR ART 
     U.S. Pat. No. 3,947,104 shows a compact imaging apparatus which projects an image upwards using a series of two fixed mirrors. 
     U.S. Pat. No. 4,875,064 shows a projecting apparatus that enlarges and displays an image on a liquid crystal display panel onto a screen provided in the projector apparatus. 
     U.S. Pat. No. 5,278,595 shows a liquid crystal television system that utilizes two fixed mirrors. 
     U.S. Pat. No. 5,521,659 shows a rear projection display apparatus designed to reduce parallax viewing error so that a user may interact with the display screen using a device such as a light pen. 
     SUMMARY OF THE INVENTION 
     The present invention comprises a rear projection console with at least one projector and a set of mirrors operating together to form an image-carrying light beam to travel within the console and across itself before the image-carrying light impinges upon the rear of the display screen to produce a relatively large, contiguous image with the at least one projector and set of mirrors being confined in a relatively small console area. The invention utilizes a unique layout of mirrors, projectors and light paths to create a single, contiguous image on a display screen. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a top view of the projector system illustrating the light beam crossing over itself in an initial position. 
     FIG. 2 is a top view of the projector system of FIG. 1 with the second mirror having been adjusted slightly so as to cause the image to shift from the initial position to a second position on the display screen. 
     FIG. 3 is a top view of the projector system with the second mirror being in a convex shape. 
     FIG. 4 is a top view of the projector system with the second mirror being in a concave shape. 
     FIG. 5 is a top view of the projector system showing two imagers projecting yet producing a singular, contiguous image on the display screen. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     In FIG. 1, reference numeral  10  generally shows the projector system of the current invention. A viewing screen  16  has a viewing axis indicated by the line “V” running perpendicularly therethrough. A first mirror  12  is positioned laterally and at an oblique angle to viewing screen  16  and at an acute angle with respect to viewing axis “V”. A second mirror  14  is positioned at an acute angle Ø 1  with respect to viewing screen  16  and at an acute angle Ø 2  with respect to first mirror  12 . A light emitter  11 , usually an imager, is positioned in an area that will not conflict or interfere with any light that is emitted. The imager  11  projects a light beam at first mirror  12 . A first peripheral ray  13   a  contacts the mirror at first edge  12   a,  a center ray  13   b  contacts the mirror at the center point  12   b,  and a second peripheral ray  13   c  contacts the mirror at second edge  12   c.  First mirror  12  reflects the beam away from the screen  16  and towards the second mirror  14 . The first peripheral ray  13   a  contacts the second mirror at a first edge  14   a,  the center ray  13   b  contacts the second mirror at the center point  14   b,  and the second peripheral ray  13   c  contacts the second mirror at the second edge  14   c.  Second mirror  14  reflects the beam towards the screen  16 . The first peripheral ray  13   a  contacts the view screen at a first edge  16   a,  the center ray  13   b  contacts the view screen  16  at a center point  16   b,  and the second peripheral ray  13   c  contacts the screen  16  at a second edge  16   c.  The rays from the imager  11  have thus passed through themselves before appearing on the screen  16  and traveling to a viewer&#39;s eye. The outward direction of the rays is generally shown by reference numeral  18 . It is apparent to one examining the flow of the light within the console that the image contained within the light beam will effectively be reversed when the light completes its path from imager to screen. However, as the imager envisioned in this application is digital in nature, it is a simple procedure to reverse the image that is to be projected before it leaves the imager thus insuring that the correct image appears on the screen in its proper orientation and form. 
     An important part of proper image formation is the placement of the first mirror  12  and the second mirror  14  within the console. FIG. 1 illustrates a standard or default condition wherein the rays projected reach the screen  16  and travel outward therefrom. FIG. 2 illustrates the same projector system  10  of FIG. 1, but the second mirror  14  has been displaced a distance “X” into a new position as indicated by numeral  14 ′. As described earlier, the rays travel from the imager  11  which projects a light beam at first mirror  12 . A first peripheral ray  13   a  contacts the mirror at first edge  12   a,  a center ray  13   b  contacts the mirror at the center point  12   b,  and a second peripheral ray  13   c  contacts the mirror at second edge  12   c.  First mirror  12  reflects the beam away from the screen  16  and towards the second mirror  14 ′ which has been moved a distance X from its previous position at  14 . The first peripheral ray  13   a  contacts the repositioned second mirror at a first edge  14   a,  the center ray  13   b  contacts the repositioned second mirror at the center point  14   b,  and the second peripheral ray  13   c  contacts the repositioned second mirror at the second edge  14   c.  The repositioned second mirror  14  reflects the beam towards the screen  16  at a different angle than the one described in FIG. 1, and therefore causes the image-carrying light beam to strike the screen  16  at a different location. The first peripheral ray  13   a  contacts the screen  16  at a first edge  16   a′,  the center ray  13   b  contacts the screen  16  at the center point  16   b′,  and the second peripheral ray  13   c  contacts the screen  16  at the second edge  16   c′.  Thus, collection of rays  18  has been displaced a distance “Y” along the screen surface  16  due to the adjustment of second mirror  14  a distance X to position  14 ′. It is in this manner that an image could be shifted to appear at a desired spot on a screen surface. In applications where there can be more than one imager producing a single, contiguous image on a screen, the ability to move the projected images to form a complete single image is strongly beneficial. 
     FIG. 3 shows the projector system of FIG. 1 in use with the second mirror  14  replaced by a convex mirror  25 . The image-carrying rays bounce off of the first mirror and then strike the convex mirror  25 . A first peripheral ray  13   a  contacts the convex mirror at first edge  25   a,  a center ray  13   b  contacts the convex mirror at the center point  25   b,  and a second peripheral ray  13   c  contacts the convex mirror at second edge  25   c.  At this point in the path from the imager to the screen, the image-carrying light, and more specifically, the beams contained therein, spread out traveling the distance from the convex mirror  25  to the screen  22 . The rays spread out a width  18 ′ to cover a large screen  22 . It is envisioned that the convex mirror  25  could still be adjusted to allow image  18 ′ movement along screen  22 . 
     FIG. 4 shows the projector system of FIG. 1 in use with the second mirror replaced by a concave mirror  30 . The light emitter  11  projects a light beam at the first mirror  12 . As described in the description of FIG. 1, a first peripheral ray  13   a  contacts the mirror at first edge  12   a,  a center ray  13   b  contacts the mirror at the center point  12   b,  and a second peripheral ray  13   c  contacts the mirror at second edge  12   c.  First mirror  12  reflects the beam away from the screen  16  and towards a concave mirror  30 . The first peripheral ray  13   a  contacts the concave mirror at a first edge  30   a,  the center ray  13   b  contacts the concave mirror at the center point  30   b,  and the second peripheral ray  13   c  contacts the concave mirror at the second edge  30   c.  The concave mirror  14  reduces the size of and reflects the beam towards the screen. The first peripheral ray  13   a  contacts the view screen at a first edge  21   a,  the center ray  13   b  contacts the view screen  21  at a center point  21   b,  and the second peripheral ray  13   c  contacts the screen  21  at a second edge  21   c.  The rays from the imager  11  have thus passed through themselves before appearing on the screen  21  and traveling to a viewer&#39;s eye. In this way, it can be perceived that the image projected by the imager can be made smaller than would normally be the case if using a flat mirror. It can also be perceived that the resulting image characterized by reference numeral  18 ″ could fit on a smaller screen or on just a portion of a large screen, and that it could also be adjusted to appear on a certain portion of the screen if the concave mirror were adjusted. The image  18 ″ could also be merged with at least one other image to form a single, contiguous image, on a display screen. 
     FIG. 5 shows two display systems of the present invention in a console  100 . Imager  51  display screen  16  and mirrors  52  and  54  are fixedly mounted within one side of console  100  and display imager  11  and mirrors  12  and  14  are fixedly mounted within the opposite side of console  100  to minimize relative movement between the components. While only two display systems are described herein, it is imagined that a plurality of display systems could be linked together within a console. Projector  11  operates to bounce first peripheral ray  13   a,  center ray  13   b,  and second peripheral ray  13   c  off of the first mirror  12 , the second mirror  14 , and onto a portion of the back of screen  16 . Projector  51  operates in a similar fashion, bouncing an image shown loosely as a first peripheral ray  53   a,  a center ray  53   b,  and a second peripheral ray  53   c  off of a first mirror  52 , a second mirror  54 , and onto a portion of the display screen  16 . Both display systems are completely contained within the console  100 . The mirrors and projectors are positioned to project images on to the single screen  16 , and by fine tuning of the second mirrors  14  and  54 , the images projected by projectors  11  and  51  can be brought together to form a single, contiguous image on view screen  16 . 
     It can be seen with the current invention that it produces an image upon a screen using a unique arrangement of mirrors that cause the image-carrying light to travel through itself before reaching the screen, thus reducing the amount of space needed for image projection. It can also be seen that the display system can be linked with similar or like units within a console to create a single, contiguous image upon a display screen. It can also be seen that the image produced by the imager can be enlarged or reduced by the utilization of convex or concave mirrors as part of the display system.