Space-invariant holographic optical interconnects in dichromated gelatin

The authors discuss recent results obtained whilst copying a binary phase Dammann grating onto dichromated gelatin (DCG). The recording set-up was designed so that the grating and its focussing lens were combined to form a single HOE. They therefore were able to construct a compact, space-invariant array generator. In addition higher, unwanted diffraction orders were filtered out. Thus, on replay, only required N×N array of diffraction orders were reconstructed without the need of an extra lens. They fully describe the recording scheme used in the copying process and outline the results obtained. Effects of phase distortion on reconstruction fidelity are discussed. Furthermore the trade off between efficiency and uniformity and the role which K ratio plays in this is mentioned