Method of manufacturing a hologram by means of nonlinear recording materials

Claim 1

A method of holographically recording an image of a coherently illuminated object with a recording medium that is non-linear over exposure ranges exceeding a predetermined value, comprising the steps of exposing an intermediate recording medium to coherent radiation from the object in a substantially linear range of the intermediate recording medium, transferring the intermediate recording on to a final recording medium in a substantially linear range of the final recording medium by projecting a uniform constant intensity beam through said intermediate recording and onto said final recording medium, and subsequest to the transfer, discarding said intermediate recording medium and exposing the final recording medium simultaneously to the coherent radiation from the object which radiation is identical to that used to expose the intermediate recording medium and to a uniform coherent reference beam of radiation only, the exposure time of the step of exposing the final recording medium to the object and reference beams being equal to the exposure time of the intermediate recording multiplied by the constant intensity of the beam used for transferring the intermediate recording and the transfer characteristic Beta of the intermediate recording medium, the relative positions of the object and intermediate recording medium being identical to the relative positions of the object and the final recording medium.

Claim 2

A method of holographically recording an image of a coherently illuminated object with a recording medium that is non-linear over exposure ranges exceeding a predetermined value, comprising the steps of exposing an intermediate recording medium to coherent radiation from the object in a substantially linear range of the intermediate recording medium, transferring the intermediate recording on to a final recording medium in a substantially linear range of the final recording medium by projecting a uniform constant intensity beam through said intermediate recording and onto said final recording medium, and subsequest to the transfer, discarding said intermediate recording medium and exposing the final recording medium simultaneously to the coherent radiation from the object which radiation is identical to that used to expose the intermediate recording medium and to a uniform coherent reference beam of radiation only, the exposure time of the step of exposing the final recording medium to the object and reference beams being equal to the exposure time of the intermediate recording multiplied by the constant intensity of the beam used for transferring the intermediate recording and the transfer characteristic Beta of the intermediate recording medium, the relative positions of the object and intermediate recording medium being identical to the relative positions of the object and the final recording medium.