Applications of a self-developing photopolymer material: holographic interferometry and high-efficiency diffractive optical elements

摘要

Abstract: In this paper the applications of a photopolymerizableholographic recording material are discussed. Theholographic recording characteristics of thephotopolymer include very high diffraction efficiencyin transmission mode and relatively low exposureenergy, typically tens of milliJoules. The recordingmaterial has a resolution of 3000 lines/mm and there isnot distortion of slanted gratings. This allows highinter-beam angles in transmission recording and makesthe material particularly suitable for the holographicrecording of diffractive optical elements. Theimplications of the resolution limit and other materialproperties for DOE fabrication are discussed in somedetail and results for the recording of on- andoff-axis focusing and beam splitting diffractiveoptical elements are presented. One of the mostsignificant advantages of this material is that it isself-developing. As well as making ordinarytransmission holography and DOE recording moreconvenient, this makes the material particularly usefulfor both live fringe and double exposure holographicinterferometry. Live fringes can be viewed as soon asany stress is applied to the object. This material'sunique self-developing properties also mean that thegrowth of the diffraction efficiency of aholographically recorded DOE can be monitored as it isbeing recorded. This type of on-line control isextremely useful in DOE fabrication particularly whencontrolling the ratio of beam splitters. !6