摘要:
The refractive index of a light transmission layer of an optical disk is set within the range of 1.45 to 1.75, the numerical aperture of a lens emitting laser light which is incident onto the light transmission layer is set to 0.65, and the wavelength range of the laser light is set within the range of 395 to 415 nm. Further, in order that aberrations fall within the range of certain acceptable values, the thickness t of the light transmission layer is set within the range of f(n)−t1≦t≦f(n)+t2, employing constants t1, t2 determined based on an acceptable value of aberration and function f(n) of the refractive index n.
摘要翻译:光盘的透光层的折射率设定在1.45〜1.75的范围内,入射到透光层上的发射激光的透镜的数值孔径设定为0.65, 激光设定在395〜415nm的范围内。 此外,为了使像差落在某些可接受值的范围内,光传输层的厚度t设定在f(n)-t1 <= t <= f(n)+ t2的范围内,采用常数t1 t2基于像差的可接受值和折射率n的函数f(n)确定。
摘要:
The refractive index of a light transmission layer of an optical disk is set within the range of 1.45 to 1.75, the numerical aperture of a lens emitting laser light which is incident onto the light transmission layer is set to 0.65, and the wavelength range of the laser light is set within the range of 395 to 415 nm. Further, in order that aberrations fall within the range of certain acceptable values, the thickness t of the light transmission layer is set within the range of f(n)−t1≦t≦f(n)+t2, employing constants t1, t2 determined based on an acceptable value of aberration and function f(n) of the refractive index n.
摘要:
An optical disc apparatus of the invention in its broader aspects, by locating, at a position displaced a predetermined distance from the focal point of a condenser lens, a light-receiving surface of a photodetector for receiving a laser beam reflected from first and second recording layers of an optical disc, is configured, when playing back a signal from a certain recording layer, to decrease the difference in a crosstalk caused by a light reflected from other recording layers.
摘要:
An optical disc apparatus of the present invention in its broader aspects is configured to have a predetermined range of A/M2, which is determined by an area A of a light-receiving surface of a photodetector to receive a reflected laser beam reflected on first and second recording layers of an optical disc, and a lateral magnification M (ratio of a condenser lens focal length fc to an objective lens focal length fo) of a light-receiving system to pass a reflected laser beam.
摘要翻译:本发明的光盘装置在其更广泛的方面被配置为具有由接收光电检测器的光接收表面的面积A确定的A / M 2的预定范围 在光盘的第一和第二记录层上反射的反射激光束,以及光接收系统的横向放大率M(聚光透镜焦距fc与物镜焦距fo的比率),以使反射激光束 。
摘要:
The present invention relates to an optical head unit and an optical disk unit using the optical head unit. The head unit includes a wavefront transforming optical element control unit to controls a wavefront transforming optical element so as not to transform wavefront of a light beam focused on a recording layer by a focusing unit due to the thickness error of a light transmission layer positioned between the recording layer and the focusing unit based on an electrical signal outputted from a first light detector, and an output control unit that controls light amount of a light beam radiated by a light emitting unit based on the magnitude of the electrical signal outputted from the light detector.
摘要:
The present invention relates to an optical head device and an optical disk unit using the same. The optical head device includes a relay lens control unit to control at least one of lenses of a relay lens unit based on an output signal outputted from a first optical detector and a power control circuit to control an intensity of a light beam emits from a light source.
摘要:
The present invention relates to an optical head device and an optical disk unit using the same. The optical head device includes a relay lens control unit to control at least one of lenses of a relay lens unit based on an output signal outputted from a first optical detector and a power control circuit to control an intensity of a light beam emits from a light source.
摘要:
There are comprised a laser light source for outputting a light beam, an optical disk having a recording/reproducing surface and a transparent substrate on the surface, an objective lens for gathering the light beam on the optical disk, a relay lens system comprising one or more lenses inserted between the laser light source and the objective lens, means for moving one or more lenses in the relay lens system toward its optical axis so as to correct sphere aberration in accordance with a thickness of the transparent substrate of the optical disk, and means for sustaining a diameter of an incident light on the objective lens when one or more lenses among the relay lenses move.
摘要:
The present invention relates to an optical head device and an optical disk unit using the same. The optical head device includes a relay lens control unit to control at least one of lenses of a relay lens unit based on an output signal outputted from a first optical detector and a power control circuit to control an intensity of a light beam emits from a light source.
摘要:
There is disclosed an optical disk constituted by covering an information recording layer formed on a substrate with a cover layer having a light transmission property, in which ranges of a thickness t and a refractive index n of the cover layer are defined. That is, a function f(n) which is not a constant regarding the refractive index n of the cover layer, and constants t1, t2 determined based on an allowable value of an aberration in the cover layer are used to set the ranges of the thickness t of the cover layer to a range of f(n)−t1≦t≦f(n)+t2.
摘要翻译:公开了一种光盘,其通过覆盖形成在具有透光性的覆盖层的基板上形成的信息记录层,其中限定了覆盖层的厚度t和折射率n的范围。 也就是说,使用关于覆盖层的折射率n不是常数的函数f(n),并且使用基于覆盖层中的像差的允许值确定的常数t 1,t 2来设定范围 覆盖层的厚度t到f(n)-t 1 <= t <= f(n)+ t 2的范围。