<title>Holographic recording properties in thick films of ULSH-500 photopolymer</title>

Holographic data storage technology

“…Both of these distort the reconstructed holograms and thus cause errors in decoding the digital data. For some photopolymers, significant advances have been made toward eliminating these undesired properties; for example, shrinkage has been reduced to less than 0.1% while sufficient useful dynamic range for recording of data has been retained [44]. There are additional problems in increasing the thickness of these materials to the millimeter scale that is desirable for holography, and even then the Bragg angle selectivity is not sufficient to allow enough holograms to be written in a common volume to achieve high data density.…”

<title>Physical properties of volume holographic recording utilizing photo-initiated polymerization for nonvolatile digital data storage</title>

“…Throughout our experimental investigation, we consistently utilized same standard pretreated samples of Polaroid ULSH-500B, with nominal thickness of L = 200pm, to minimize the material variations in the experimental analysis [11]. The present analysis extends the initial results in optically pre-exposed samples [7], including standard thermally annealed samples.…”

Influence of photoinitiator concentration and polymerizing light intensity on conversion of acrylic manomers

“…Photopolymers are attractive because they are inexpensive, highly flexible, easily processable and have tunable properties; equally, several advantages over inorganic photorefractive crystals such as photosensitivity and dynamic range have been demonstrated [1][2][3][4][5][6]. During holographic recording, the polymerization of monomers in the corresponding matrix proceeds predominantly in the high intensity regions which results in monomer gradient between high and low intensity regions [7].…”

“…Most holographic photopolymer systems are based on one of two mechanisms of polymerization -either cationic ring opening polymerization (CROP) or free-radical polymerization [1][2][3][4][5][6]. This article considers free-radical polymerization systems.…”

“…During the last decade significant progress has been made in development of photopolymerizable compositions for holographic data storage [1][2][3][4][5]. Photopolymers are attractive because they are inexpensive, highly flexible, easily processable and have tunable properties; equally, several advantages over inorganic photorefractive crystals such as photosensitivity and dynamic range have been demonstrated [1][2][3][4][5][6].…”