Curved viewing glass for observing objects under water - has uniform curving from optical centre, where curvature is zero, to edges of glass, has one or more centres of curvature

摘要

The curve in the glass (1) reduces uniformly towards the edges (3) from the optical centre (2). Where there is only one optical centre where the curvature is nil. Where there are two optical centres, the curvature along the connection line between the two centres is nil. The distance between the two optical centres will correspond to the distance between the eyes of a human. USE/ADVANTAGE - For divers masks, helmets, glasses, underwater laboratories, underwater vehicles etc. Provides a large field of vision, does not allow for any non permissible viewing mistakes and possesses very little picture distortion.