Angle Filter

The GSI Angle Filter transmits light based on angle of incidence (AOI). At normal incidence the filter acts like a neutral linear polarizer. Off-normal,  transmission declines with increasing AOI ending in a rejection band above 60°.  Transmission is color neutral over tilt and azimuth angles.

GSI Angle Filters are free of internal structures, thereby avoiding unwanted straylight and image artefacts. As such, the filter can be used  in both imaging and illumination systems. Applications include ambient rejection, stray-light control, artifact mitigation and privacy filtering.