Sony Corporation

Sony Group Corporation

Toyokazu Takahashi

Satoshi Hineno

Kiyoshi Toyota

Hiroyuki Sakakibara

Motoo Aiba

Kenichi Ogawa

Kouhei Anju

Shinya Ootani

Liquid crystal is prevented from leaking out into a terminal hole in a liquid crystal injection process, and the productivity of a liquid crystal light control device is improved. A liquid crystal light control device according to the present technology includes a plurality of liquid crystal layers, terminals provided for respective electrodes disposed to face each other across the liquid crystal layers, and terminal holes formed above the terminals, and an injection mark of a liquid crystal for the liquid crystal layer is formed on a back face side which is a face on a side opposite to a face that has been opened by the terminal hole.

Liquid crystal light control device, and method of manufacturing liquid crystal light control device

Provided is an objective lens for which expressions 0.83&#x3c;(p/p)&#x3c;1.17 and 0.83&#x3c;(p/p)&#x3c;1.17 or expressions 0.80&#x3c;(p/p)&#x3c;1.20 and 0.86&#x3c;(p/p)&#x3c;1.14 are satisfied, where pis the ratio of fifth-order spherical aberration to third-order spherical aberration, the spherical aberrations being caused by a difference in the thickness of a cover layer of an optical recording medium, pis the ratio of fifth-order spherical aberration to third-order spherical aberration, the spherical aberrations being caused by a change in the temperature of an environment of the objective lens, and pis the ratio of fifth-order spherical aberration to third-order spherical aberration, the spherical aberrations being caused by a change in incident magnification.

Objective lens, optical pickup apparatus using the same, optical recording/reproduction apparatus using the same, and method of correcting aberration using the same

An optical pickup device includes: a light source that emits a light beam; a divergence-angle converting lens that converts an angle of divergence of the light beam emitted from the light source and emits the light beam; and an object lens displaceable in a tracking direction that receives incidence of the light beam, the angle of divergence of which is converted by the divergence-angle converting lens, and converges and emits the light beam, wherein spherical aberration equivalent to an amount that can offset astigmatism caused when the object lens is displaced is given to the divergence-angle converting leans, and spherical aberration that can offset the spherical aberration given to the divergence-angle converting leans is given to the object lens and comatic aberration that can offset comatic aberration caused by the spherical aberration given to the divergence-angle converting lens when the object lens is displaced is given to the object lens.

Optical pickup device and optical disk apparatus using the same

The present invention is relative to an objective lens () for an optical pickup, having a numerical aperture not less than 0.8, and adapted for correcting the chromatic aberration at an image point on an optical axis for light with a wavelength within several nm about a reference wavelength which is not larger than 420 nm. This objective lens is made up by a first lens set GR, having a compound surface Sof a refractive surface Sand a diffractive surface S, and a second lens set GR, having a positive refractive power, looking from the light source side. The compound surface of the first lens set is formed by adding the diffractive surface having the positive refractive power to the refractive surface which is an aspherical surface having the negative refractive power. The lens forming the second lens set is a single lens including at least one aspherical lens. This objective lens is small-sized, permits effective correction of chromatic aberration and enables the laser light to be converged to close to the diffraction threshold.

Optical pickup-use object lens, optical pickup and optical disk unit

An objective lens unit for an optical pickup used for recording and/or reproducing information signals from an optical disc. The objective lens unit includes a resin layer ( ) having, sequentially from an object side, a first surface S as an aspherical surface and a second surface S as an aspherical surface, at least one of the first surface and the second surface including a diffractive surface, and a lens of glass ( ) having the second surface S as an aspherical surface and a third surface S as an aspherical surface. The lens unit is corrected for the chromatic aberration on an image surface on the optical axis with respect to the light of a reference wavelength not larger than 420 nm within several nm of the reference wavelength, with the numerical aperture of the lens unit being not less than 0.8. This objective lens unit is able to converge the laser light close to the limit of diffraction on the image surface.

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Tokyo, Japan

Toyokazu Takahashi