摘要:
A two-color hologram recording/reproducing apparatus is capable of directing interferable signal light and reference light into a hologram recording medium to record an information signal carried by the signal light. The hologram recording medium is sensitive to a first light at a first wavelength in an ultraviolet or short-wavelength visible light band to develop light induced absorption. The apparatus includes a light source for irradiating the hologram recording medium with the first light, a laser light source for irradiating the hologram recording medium with signal light and reference light at a second wavelength longer than the first wavelength after the first light is irradiated, and a gate light source for directing gate light at a third wavelength into the hologram recording medium. The gate light causes the hologram recording medium to develop a recording sensitivity to activate or inactivate a refractive index grating in accordance with existence or non-existence of a light interference pattern formed by the signal light and the reference light.
摘要:
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.
摘要:
A two-color holographic recording apparatus reduces error signals possibly included in reproduced digital data signals. The two-color holographic recording apparatus has first, second and third light shutters for passing or blocking gate light, signal light and reference light incident on a recording medium respectively, and a controller for controlling the respective states of the first, second and third light shutters.
摘要:
A hologram recording apparatus is capable of directing interferable signal light and reference light into a hologram recording medium to record an information signal carried by the signal light. The hologram recording medium is sensitive to a first light at a first wavelength in an ultraviolet or short-wavelength visible light band to develop light induced absorption. The apparatus includes a light source for irradiating the hologram recording medium with the first light, and a laser light source for irradiating the hologram recording medium with signal light and reference light at a second wavelength longer than the first wavelength after the first light is irradiated.
摘要:
A holographic recording medium exhibiting a high recording sensitivity without execution of reduction treatment. A system records information on the holographic recording medium by using a gating light within a wavelength band causing less optical damage to the holographic recording medium. The holographic recording medium includes a single crystal of lithium niobate (LiNbO3) or lithium tantalate (LiTaO3) containing Mn as a dopant.
摘要:
A stoichiometric single crystal of lithium niobate or lithium tantalate is produced by pulling a single crystal of lithium niobate or lithium tantalate having a molar fraction of Li2O/(Nb2O5+Li2O) or Li2O/ (Ta2O5+Li2O) of at least 0.490 and less than 0.500, from a melt of a composition having a molar excess of Li over a stoichiometric composition of lithium niobate or lithium tantalate. The single crystal has 0.1 to 3 mol % of at least one element selected from the group consisting of Mg, Zn, Sc and In based on a total amount of elements Nb and Li, or a total amount of elements Ta and Li. The single crystal has substantially no absorption in the visible light region.
摘要翻译:铌酸锂或钽酸锂的化学计量单晶通过将具有至少0.490摩尔分数的Li 2 O /(Nb 2 O 5 + Li 2 O)或Li 2 O /(Ta 2 O 5 + Li 2 O)的摩尔分数的铌酸锂或钽酸锂的单晶拉伸并且小于 0.500,来自具有摩尔过量的Li的组合物的熔体,其化学计量组成为铌酸锂或钽酸锂。 基于元素Nb和Li的总量或元素Ta和Li的总量,单晶具有选自Mg,Zn,Sc和In中的至少一种元素的0.1至3mol%。 单晶在可见光区域基本上没有吸收。
摘要:
An optically functional device comprising a ferroelectric single crystal substrate and polarization-inverted structures formed at portions of the substrate at a temperature of not higher than the Curie temperature by an electron beam scanning irradiation method or a voltage application method and designed to control light passed through the polarization-inverted portions, wherein a LiNbO3 crystal having a molar ratio of Li/Nb within a range of from 0.95 to 1.01, is used as the substrate, so that the propagation loss of light passed through the polarization-inverted portions immediately after formation of the polarization-inverted structures, is not more than 2%.
摘要:
A single crystal of lithium niobate or lithium tantalate may be grown from a melt of a composition having a molar excess of Li compared to a melt having the stoichiometric amount of lithium, and having a molar fraction of Li2O/(Nb2O5+Li2O) or Li2O/(Ta2O5+Li2O) within a range of at least 0.490 and less than 0.500. The single crystal also has at least one element selected from the group consisting of Mg, Zn, Sc and In, in an amount of from 0.1 to 3.0 mol % based on the total amount of the elements, Nb and Li, or the total amount of the elements, Ta and Li.
摘要翻译:铌酸锂或钽酸锂的单晶可以从具有摩尔过量的Li的组合物的熔体与具有化学计量的锂的熔体相比生长,并且具有Li 2 O /(Nb 2 O 5 + Li 2 O)或Li 2 O的摩尔分数 /(Ta2O5 + Li2O)在0.490以上且小于0.500的范围内。 单晶还具有选自Mg,Zn,Sc和In中的至少一种元素,相对于元素的总量,Nb和Li为0.1〜3.0摩尔%,或者总量 的元素,Ta和Li。
摘要:
An optically functional device comprising a ferroelectric single crystal substrate and polarization-inverted structures formed at portions of the substrate at a temperature of not higher than the Curie temperature by an electron beam scanning irradiation method or a voltage application method and designed to control light passed through the polarization-inverted portions, wherein a LiTaO3 crystal having a molar ratio of Li/Ta within a range of from 0.95 to 1.02, is used as the substrate, so that the propagation loss of light passed through the polarization-inverted portions immediately after formation of the polarization-inverted structures, is not more than 2%.
摘要:
An optical material includes lithium tantalate, and a molar composition ratio of lithium oxide and tantalum oxide (Li2O/Ta2O5) in the lithium tantalate is in the range of 0.975 to 0.982. Since an optical material having a high refractive index is provided in an optical unit, at the same focal distance, a lens thickness can be significantly reduced. As a result, an optical electronic component and an optical electronic device including the optical material has a reduced size and thickness and is highly functional.
摘要翻译:光学材料包括钽酸锂,并且钽酸锂中的氧化锂和氧化钽(Li 2 O / Ta 2 O 5)的摩尔组成比在0.975至0.982的范围内。 由于在光学单元中设置了具有高折射率的光学材料,所以在相同的焦距下,可以显着地减小透镜厚度。 结果,包括光学材料的光学电子部件和光学电子器件具有减小的尺寸和厚度并且具有高功能性。