Device for the suppression of the beam of an order zero emerging in the application of a hologram polarized

摘要

The birefringent plate (5) is lit by both a zero order beam (3) emitted from a hologram illuminated in polarised light, and by a diffracted beam (4) emerging from the hologram. The plate is constructed so that one of the beams emerges from it with its plane of polarisation rotated by (90) degrees and the other emerges with hardly any rotation. Both emerging beams illuminate a polariser (9). The polariser has its plane of maximum transmittance parallel to the plane of polarisation of the diffracted beam emerging from the plate.