Image mask for microfilm roll handler

Claim 1

An image mask assembly for a microfilm roll handler having reels accepting microfilm wound upon and extending between said reels and under a first stationary glass, the lower surface of which defines a focal plane for the microfilm roll handler, the image mask assembly comprising: a frame supported below and biased toward said first stationary glass; a second stationary glass mounted on and biased by said frame toward said first stationary glass to capture said film between said first and said second stationary glasses; and an insert slideably mounted by said frame and movable with respect to said frame and said second stationary glass, said insert including a bar defining a grasping portion extending beyond said frame, two end members joined one at each end of said bar and extending in one direction from said bar and beneath said second stationary glass, said end members having terminal portions, and a thin ribbon of opaque material secured to said terminal portions and extending generally parallel to said bar defining an opaque area which may be positioned relative to said frame and said first and said second stationary glasses for blocking light through a portion of said film and thereby masking selected portions of an image projected by said film when positioned by movement of said bar.