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This hardware was used to project full color digital images by combining images from three different colored images of red, blue, and green. A very clever (and lovely looking) dichroic prism assembly divided light from an arc lamp into three different color channels to illuminate each "silvered" micromirror display. The micromirrors would reflect the light back the way it came based on how the elements in the array are switched on or off to create each color image. The reflected images are visible through an output opening where the projection lens (not present) would be mounted.
 
 One end of the device has something that looks like an eyepiece and could provide a fine view of the micromirrors, if they were present and if the "eyepiece" didn't have a element in it that looked like window version of a disco ball (a refractive beam integrator). An arc lamp was supposed to shine into that "eyepiece" and the shape of the arc spot was to be "smoothed" by the integrator. If this is removed we would be looking into the prism assembly and see three different colored views through the prism faces where the micromirrors went.
 
 After the integrator is a turning mirror at "wrist" of the device. This is a "cold mirror" that only reflect visible light and lets IR pass. This is important because they don't want to cook the micromirror devices with heat, as the visible light alone is enough lost energy.
 
 After the cold mirror is a fast multielement coated condenser assembly that looks like a good photographic lens. It would be a good lens for a small film chip, but here its purpose is something else. This lens is designed to project an image of the integrator into or beyond (to infinity, as a collimator) into the center of the projections lens (not included). The purpose of the condenser lens was also to collimate the light so that the dichroic prism would work correctly as the coatings are angle sensitive.
 
 After the the lens the elbow of the device appears to be a fixed front surface mirror designed to redirect the light from the lens into the prism assembly. The prism assembly is designed to break white light into red, blue, and green channels. The light is reflected off of prism faces that only reflect those colors towards the windows where the "silvered" faces of the micro-mirror spatial light modulators would have displayed their bright faces. The bright image on these faces would be returned along the incoming light path and be recombined where they were separated. Some of the image would reflect back towards the arc lamp, but half of it would exit from the open face of the prism that affords the view of all color channels. If the device were assembled and working the view would be of the brightest and smallest color TV you had ever seen. That would be the image projected by the absent projection lens.
 
 It is clear that this die cast housing was precision machined, all of the parts were very expensive, the lens appears to be best as a collimator, and the prism is a fine piece of work. The prism assembly actually holds the three displays at 45 degree angles to present the "right" image at the output. The facet angles of the prism are complex, and these probably cost hundreds of dollars if purchased new and individually, if you could by it....
 
 Ah, the wonders of surplus. You wonder, "What can I use this for?" There are many interesting answers. One is making your own color separation camera with 3CCDs or film drives. Or perhaps you would like to divide white light into three separate color channels. The collimating lens alone could be worth the price of the assembly. this lens only seems to handle a point of light on axis very very well. Light reflected from the micromirrors also is dumped into the housing and conducted to fins for cooling.

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