Photorefractive material
AssigneesDirector General of National Institute for Research in Inorganic Materials, Pioneer Corporation
InventorsKenji Kitamura, Yasunori Furukawa, Shunji Takekawa, Myeongkyu Lee, Hideki Hatano, Satoru Tanaka, Takashi Yamaji
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Abstract
A photorefractive material provides a high photosensitivity without reduction. The material comprises a single crystal of terbium (Tb)-doped niobate or tantalate. The single crystal is a single crystal of lithium niobate (LiNbO3) whose molar fraction of [Li2O]/([Li2O]+[Nb2O5]) lies in a range of 0.482 to 0.505, or a single crystal of lithium tantalate (LiTaO3) whose molar fraction of [Li2O]/([Li2O]+[Ta2O5]) lies in a range of 0.482 to 0.505. The amount of terbium added in the photorefractive material ranges from 10 weight ppm to 1000 weight ppm.
Claims8
A process of recording data on a two-color holographic recording medium comprising the steps of:
- irradiating the recording medium with gate light having a first wavelength;
- and
- irradiating the recording medium with reference and signal light having a second wavelength to record a hologram;
- wherein the recording medium comprises a single crystal of terbium-doped lithium niobate,
- wherein said crystal exhibits a stoichiometric composition,
- wherein said crystal has not undergone reduction,
- wherein said lithium niobate crystal has a molar fraction of [Li2O]/([Li2O]+[Nb2O5]), and
- wherein said molar fraction ranges from about 0.490 to about 0.505.
A process of recording data on a two-color holographic recording medium comprising the steps of:
- irradiating the recording medium with gate light having a first wavelength;
- and
- irradiating the recording medium with reference and signal light having a second wavelength to record a hologram,
- wherein the recording medium comprises a single crystal of terbium-doped lithium tantalate,
- wherein said crystal exhibits a stoichiometric composition,
- wherein said crystal has not undergone reduction,
- wherein said lithium tantalate crystal has a molar fraction of [Li2O]/([Li2O]+[Ta2O5]), and
- wherein said molar fraction ranges from about 0.490 to about 0.505.
Dependencies are inferred from the claim text.