Document Type

Conference Paper

Rights

Available under a Creative Commons Attribution Non-Commercial Share Alike 4.0 International Licence

Disciplines

1.3 PHYSICAL SCIENCES, Optics, 3.2 CLINICAL MEDICINE, Ophthalmology

Publication Details

Event: SPIE Photonics Europe, 2020, Online Only

Abstract

Optical diffusers have uses in laser applications and machine vision. Typical fabrication at a commercial level requires master production and the stamping/copying of individual elements at scale. This expensive, indirect process inhibits custom diffusers at reasonable cost. Previously the authors published a novel, direct, single beam method of recording customizable and controllable volume holographic diffusers by manipulating laser speckle and recording the pattern in photopolymer. This method allows for beam-shaping to produce diffusion patterns of various sizes and shapes. In this work, the direct method of recording controllable holographic diffusers is refined to improve diffuser performance (i.e., a decrease in zero order strength) for a simple diffuser. This is achieved through optimising the recording conditions (exposure energy, power and layer thickness) for a given photopolymer formulation. Significant improvement in the diffuser efficiency is observed through the optimisation process for a particular speckle size, resulting in a five-fold decrease in the remaining zero order. Kogelnik Coupled Wave Theory (KCWT) is explored as a first step towards developing an appropriate model for the behaviour of holographic elements recorded with interference patterns formed through stochastic processes, such as speckle patterns.

DOI

https://doi.org/10.1117/12.2555774

Funder

Enterprise Ireland


Share

COinS