Optical holography in dichromated gelatin

Thesis

Coupled wave theory is used to investigate the properties of high quality holograms recorded in dichromated gelatin. Initially, the properties of planar reflection gratings are studied in order to characterize the behaviour of the recording material in detail. Dichromated gelatin is then used to fabricate more sophisticated holograms for several applications.

Chapter 1 contains an introduction to holography, holographic optical elements and coupled wave theory. Chapter 2 contains a detailed review of dichromated gelatin based on published literature and on experimental observations made during work for this thesis. In Chapter 3 the non-linearity of the recording characteristic and changes in the bulk properties of the material during processing are determined. In Chapter 4 the non-uniformity of planar gratings is investigated by making a detailed comparison with a coupled wave theory in which the grating parameters are functions of depth. The effect of different processing procedures on these non-uniformities is demonstrated. In Chapter 5 the mechanism behind the formation of real-time gratings in dichromated gelatin is determined by applying a dynamic form of coupled wave theory. The source of diffraction is found to be a pure absorption grating. In Chapter 6 the use of dichromated gelatin as a medium for copying holograms and for recording efficient noise gratings is demonstrated. In Chapter 7 a theoretical model of holographic optical elements based on vectorial coupled wave theory is presented and is used to investigate the effects of polarisation. In Chapter 8 an optical method for the measurement of distance is developed using the dispersive properties of an on-axis holographic lens. Conclusions are then presented in Chapter 9.

Authors: Newell, J; Newell, Chris

• Publication date: 1987
• DOI: 10.5287/ora-5zvjnoj4v
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: University of Oxford
• Language: English
• Subjects: Holography