Permanent color transparencies on single substrates and methods for

Abstract

Color transparencies having more than one imaged dichroic filter, and an imaged neutral density filter, layered on one side of a single glass substrate, and processes for making the same, are disclosed. In one embodiment, the color transparency is produced by a deposition process including the steps of coating a glass substrate with a photoresist and developing an image thereupon, depositing alternating layers of high and low refractive index dielectrics to form a dichroic layer of a primary subtractive color, stripping the photoresist from the glass, preparing at least one additional imaged dichroic filter on the first, and preparing a neutral density filter on the substrate on the side having the layered dichroic filters. A red antihalation coating may be applied to the lower surface of the glass substrate prior to exposing the photoresist to prevent undesirable exposure of additional portions of the photoresist layer. In an alternative embodiment, an etching process is utilized whereby stop-etch layers are deposited between each layer of the color transparency. The stop-etch layers prevent image distortion and uneven coloring during the etching process such that a high resolution color transparency is produced.