Provided is a photopolymer composition that may exhibit low volume shrinkage during holographic recording and may prevent a photosensitive dye from remaining unbleached after holographic recording.

The present disclosure provides a mobile terminal comprising: a main body of the terminal; a holography module attached to the main body of the terminal and positioned so as to output a holographic image into a preset space; and a first camera module arranged in the direction of the preset space so as to film the holographic image. Also, the present invention provides a system for controlling holography comprising the mobile terminal and a target apparatus. The target apparatus is configured so as to film the holographic image by communicating with the mobile terminal or to analyze the holographic image and generate an operational command corresponding thereto.

We describe a LCOS (liquid crystal on silicon) telecommunications light beam routing device, the device comprising: an optical input; a plurality of optical outputs; a LCOS spatial light modulator (SLM) in an optical path between said input and said output, for displaying a kinoform; a data processor, coupled to said SLM, configured to provide kinoform data for displaying said kinoform on said SLM; wherein said kinoform data defines a kinoform which routes a beam from said optical input to a selected said optical output; wherein said data processor is configured to input routing data defining said selected optical output and to calculate said kinoform data for routing said beam responsive to said routing data; and wherein said data processor is configured to calculate said kinoform data by: determining an initial phase pattern for said kinoform; calculating a replay field of said phase pattern; modifying an amplitude component of said replay field to represent a target replay field for said beam routing, retaining a phase component of said replay field to provide an updated replay field; performing a space-frequency transform on said updated replay field to determine an updated phase pattern for said kinoform; and repeating said calculating and updating of said replay field and said performing of said space-frequency transform until said kinoform for display is determined; and outputting said kinoform data for display on said LCOS SLM.

The invention relates to techniques for producing a holographic optical element, HOE, by replication of a master HOE. More particularly, the invention relates to techniques for flexibly adjusting the diffraction efficiency of the HOE. An adjustable settable optical element (54) can be used to change the intensity and/or polarisation of light during an illumination process.