<title>Experimental study on mechanical, thermomechanical, and optomechanical behaviors of holographic materials</title>

Abstract

This paper discusses material behaviors of holographic materials in terms of mechanical, thermomechanical properties and their effects on optical efficiency. Experiments were carried out to characterize coefficient of thermal expansion, stress strain curves, and dynamic mechanical behaviors of photopolymers. It has been found that in-plane deformation of photopolymer has a minimum effect on the diffraction efficiency while out-of-plane deformation can significantly contribute to the diffraction efficiency of holographic optical elements.

Temperature sensitivity of passive holographic wavelength-division multiplexers–demultiplexers

“…However, the inconsistency of the properties of the polymeric materials makes the estimation difficult. 30 The photopolymer shrinks as much as 5% during the formation of the hologram and tends to stablize after heat treatment. 31 Other studies indicate that the value of the CTE is much larger than that of Mylar.…”

“…31 Other studies indicate that the value of the CTE is much larger than that of Mylar. 30 We extracted the CTE of Mylar from Ref. 30, ␤͑Mylar͒ Ϸ 4.3 ϫ 10 Ϫ5 ͞°C, T ϭ Ϫ50 ϳ 100°C.…”

“…30 We extracted the CTE of Mylar from Ref. 30, ␤͑Mylar͒ Ϸ 4.3 ϫ 10 Ϫ5 ͞°C, T ϭ Ϫ50 ϳ 100°C. Meanwhile, the typical CTE value of polymeric materials is approximately 10 Ϫ4 ͞°C ͑e.g., for polyvinyl chloride, ␤ ϭ 4.7 ϫ 10 Ϫ4 ͞°C͒, 32 which is far too big compared with the BK7-glass substrate we used to hold the hologram.…”