Holographic Photopolymer Material for Holographic Recording of Phase Diffraction Structures.
Holographic Photopolymer Material (HPPM) is a multicomponent mixture of organic agents.
This mixture is applied on glass, plastic or film substrates as amorphous layer having 10-100 mm thickness. The photopolymer layer, as a rule, contains a polymer binder, photopolymerizing monomers, and a photoinitiating system. A dye-sensitizer provides sensitivity of the material in the spectral region of the recording laser.
The monomers polymerization occurs as a result of chemical reaction initiated by light. It leads to the local changes in refractive index of irradiated layer points. During hologram recording the light distribution is given as an interference pattern formed by the object and reference beams.
The dye and initial monomer concentrations in the irradiated layer points decrease, while the polymer concentration grows, with the concentration gradient causing the diffusion of monomer mobile molecules. Polymerization reaction passes most effectively owing to the gel-effect, in antinodes of an interference pattern; as a result, the volume phase diffraction grating (hologram) is formed.
HPPM compositions, sensitized by various dyes have been developed for the first time in Novosibirsk Institute of Organic Chemistry SB RAS. These compositions provide sensitivity to red, green and blue ranges of a spectrum. The typical parameters of one of such a HPPM are the following: (HPPM show the following typical parameters:)
- Sensitivity spectral range – 600-680 nm
- Sensitivity (on wavelength 633 nm) – 50 mJ/cm2
- Layer thickness (variable) – 30¸90 mm
- Material resolution – 2000 lines/mm
- Diffraction efficiency (for He-Ne l = 633 nm) – 30¸40%
HPPMs are considered as perspective recording mediums, suitable for various applications:
- in picture holography for 3D portraits, still-life pictures and other compositions;
- in security holography to protect labels, signs, identifiers, badges etc., with unrepeatable 3D images, and secret codes;
- in holographic memory systems as a recording medium (holographic disks, films, volume mediums) with huge capacity, up to 1 Тb/cm3, reading / recording speed up to 1 Gb/s.
- Holographic optical elements and photon crystals are complex periodical micro- and nanodimensional structures. The similar structures make it possible to manipulate by light, which significantly increases the opportunities of light flows management
- in optical communication systems - connectors, switches, diffraction filters of fiber optic communication lines, etc.;
- in optical memory and imagesvisualization systems - light flows management elements of displays, projectors, optical memory devices, etc.;
- also it can be viewed as a step towards the creation of optical computer.
- HPPM for transmitting phase diffraction structures record is an optimum recording medium for teaching experiments at schools, colleges, institutes or universities. This medium allows to use a simple and widespread He-Ne laser. Formation of holograms for small time (minutes) and evident image demonstrations has become possible due to such HPPMs.
During holographic recording in photopolymer the image visualizes at once, the additional past treatment after hologram formation being possible, but optional. The advantage of photopolymer is complete absence of wet past treatment process as compared with silver halide layers.
The original 3D-image formation occurs during the hologram recording in photopolymer, which is impossible during the embossed hologram formation.
Patent RU № 2222038 of 08.01.2002 «Photopolymer composition for hologram recording»
We receive the orders to produce photopolymeric materials for holographic recording of transmitting phase diffraction structures (HPPM633). The material is sensitive to wavelength of He-Ne laser (633 nm). The production of HPPM633 ranges from one unit to the tens experimental samples on a glass substrate (7.6´2.6 см2). Unit price per sample is 500 rubles and higher.
N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry,
Siberian Branch of the Russian Academy of Sciences
9, Acad. Lavrentiev Ave, 630090, Novosibirsk, 90, Russsia
PhD. Vladimir Vladimirovich Shelkovnikov, Head of the Laboratory