Blocking zero-order light in phase shift hologram generation

摘要

A method of forming an image comprising providing a device 20 for imparting respective phase-shifts to different regions of an incident wavefront. The phase shifts give rise to an image in a replay field, 170 and causing zero-order light to be focused into a region between the replay field 170 and the device. Light from laser 12 is focused by lens 130 upon a reflecting device, such as a mirror 140. Reflected light is directed via lens 160 to spatial light modulator (SLM) 20. Image information is therefore provided light at an imaging plane 170, whilst zero-order light is returned to the reflecting device to reduce unwanted noise in the replay field.