Diffusing plate

Abstract

Abstract PURPOSE: To make it possible to easily produce a diffusing plate such as the focal plane of a camera having desired diffusing characteristics, through the change in the patterning of a mask of a fine structure, which is formed on a soluble substrate, by dissolving the substrate through the mask. CONSTITUTION: A photosensitive film 4 of a photosensitive resin is applied to a substrate 3 of acid-soluble glass, and a pattern 5 printed on glass 6 is brought into contact therewith for an exposing purpose at 7. As a result, the insensitive or photosensitive portion is dissolved and removed to leave a net-shaped photosensitive film 4 having a net width desirably less than 10 microns. After the side of the substrate 3 left unetched is protected by a protecting film 9, the surface of the substrate 3 is etched with a treating liquid such as nitric acid. After the film 4 is then removed, the surface is softly etched to smoothen the rough portions thereby to reduce the drawback that the range finding accuracy is deteriorated and that there is abrupt difference n brightness between the center and the peripheral portion. COPYRIGHT: (C)1979,JPO&Japio

Inventors

• 👤 Toshiaki Takahashi
• 👤 Kazumi Nagao
• 👤 Yoichi Okuno

Bibliographic Details