Ocular protective apparatus

Abstract

A laser shield (FIG. 3) for providing ocular protection against laser hazards, while still providing high photopic or scotopic transmittance and good color discrimination is disclosed. This laser shield comprises a holographic optical notch filter mirror (102) having an optical surface such that the angle (104) made by an incoming laser beam (114), which is aimed by the pupil of the user, with respect to the normal of the optical surface is less than the corresponding angle (108) made by the same incoming laser beam (114) with respect to the physical surface of the substrate. This decrease in the effective angle of incidence reduces the spectral shift of the notch (which defines the frequency that is reflected), thereby providing increased protection for the same range of angles of incidence. The holographic mirror optical surface formed can be the analog of a conventional spherical, hyperbolic, parabolic, elliptical or other aspheric mirror.

Dependencies are inferred from the claim text.