Abstract:
An optical pickup apparatus used in an optical data recording/reproducing apparatus for reading/reproducing data on an optical recording medium, including a light source, a diffracting device configured to transmit a light beam and to diffract a light beam reflected from the optical recording medium, an optical device having a reflecting portion and a transmitting portion configured to reflect one part of the light beam emitted from the light source and to transmit another part of the light beam to the optical recording medium and from the optical recording medium, and a photodetecting device to detect the light beam from the optical recording medium for signal light detection, and the light beam reflected by the reflecting portion of the optical device for monitor light detection of the light source.
Abstract:
An optical head which records data onto an optical data recording medium and reproduces the data therefrom includes a laser light source, a collimator lens, an objective lens, a light splitting device arranged between the laser light source and the objective lens, for splitting the emitted light from the laser light and a reflected light from the optical data recording medium. A diffraction grating is provided to which only the reflected light split at the light splitting device is incident to, and which leads the reflected light split at the optical element onto a photo-detector. Thereby, an optical head of high effectiveness in utilization of light and low cost can be obtained.
Abstract:
An optical pickup apparatus used in an optical data recording/reproducing apparatus for reading/reproducing data on an optical recording medium, including a light source, a diffracting device configured to transmit a light beam and to diffract a light beam reflected from the optical recording medium, an optical device having a reflecting portion and a transmitting portion configured to reflect one part of the light beam emitted from the light source and to transmit another part of the light beam to the optical recording medium and from the optical recording medium, and a photodetecting device to detect the light beam from the optical recording medium for signal light detection, and the light beam reflected by the reflecting portion of the optical device for monitor light detection of the light source.
Abstract:
An optical pickup apparatus used in an optical data recording/reproducing apparatus for reading/reproducing data on an optical recording medium, including a light source, a diffracting device configured to transmit a light beam and to diffract a light beam reflected from the optical recording medium, an optical device having a reflecting portion and a transmitting portion configured to reflect one part of the light beam emitted from the light source and to transmit another part of the light beam to the optical recording medium and from the optical recording medium, and a photodetecting device to detect the light beam from the optical recording medium for signal light detection, and the light beam reflected by the reflecting portion of the optical device for monitor light detection of the light source.
Abstract:
An object detection apparatus includes an incident optical system, which includes light source units and a combining unit combining light beams emitted from the light source units; a deflection unit including rotating reflection parts that deflect the light beams to scan and be irradiated on a predetermined range of an object; an imaging unit forming an image based on the light from the predetermined range of the object; and an optical detection unit detecting the object based on the light received via the imaging unit. Further the combining unit combines the light beams such that each of the combined light beams passes a single light path when projected onto a predetermined plane, and each of the light paths exists outside a region of the deflection unit when projected onto the first plane.
Abstract:
A wavelength conversion element includes a substrate made of LiTaO.sub.3 of non-linear medium, a three-dimensional waveguide formed in the substrate and a second harmonic generation portion for defining a change in refractive index in the waveguide with a period .LAMBDA. and generating a second harmonic of a fundamental wave introduced into the wave guide, where .LAMBDA.=2 m.pi./{.beta.(2.omega.)-2.beta.(.omega.)}, m is a natural number, .omega. is a frequency of fundamental harmonic, .beta.(.omega.) is a propagation constant of the fundamental wave, and .beta.(2.omega.) is a propagation constant of second harmonic.
Abstract translation:波长转换元件包括由非线性介质的LiTaO 3构成的衬底,形成在衬底中的三维波导和用于限定波长中的折射率随时间LAMBDA产生二次谐波的二次谐波产生部分 引入波导的基波,其中LAMBDA = 2m pi / {β(2ω)-2β(ω)},m是自然数,ω是基波的频率,β(ω)是 基波的传播常数,β(2ω)是二次谐波的传播常数。
Abstract:
An optical shutter device comprises an electro-optic layer of a material that shows the electro-optic Kerr effect, an array of shutter regions defined on the electro-optic layer for controlling a passage of an optical beam through the layer, a plurality of electrodes provided on the electro-optic layer in correspondence to the shutter regions for applying a predetermined electric field upon energization, a driver circuit connected to each pair of the electrodes for energizing the same independently from each other, a biasing circuit connected to the plurality of electrodes for applying a predetermined d.c. bias voltage thereto, a switching circuit for inverting the polarity of the d.c. bias voltage, a first polarizing device provided above the electro-optic layer for causing a rotation of the polarizing plane of the optical beam in a first angular direction, and a second polarizing device provided below the electro-optic layer for causing a rotation of the polarizing plane of the optical beam in a second, opposite angular direction.
Abstract:
In a laser printer or the like, for the purpose of increasing a recording speed, the number of revolutions of a laser beam deflector is not increased but a plurality of scanning lines are simultaneously scanned. To this end, a plurality of laser beams with an angle of incidence slightly varied are simultaneously incident upon one and the same laser beam deflector. In the event that places for installation of a plurality of light sources are hindered each other by other light sources, light sources different in polarization surface from each other are used, and when beams are combined by means of a polarization beam combiner, a combined beam which is different in angle of emergence through a fine angle each other can be obtained without loss of light.
Abstract:
P-polarized light beam passing through an fθ lens passes through a polarization beam splitter, is converted into S-polarized light beam by a quarter-wave plate and a reflecting mirror, re-enters the polarization beam splitter, and is reflected at the polarization beam splitter in the −Z direction. An optical path of a light beam between a polygon mirror and the fθ lens, between the fθ lens and the polarization beam splitter, between the polarization beam splitter and the quarter-wave plate, between the quarter-wave plate and a reflecting mirror, between the reflecting mirror and the quarter-wave plate, and between the quarter-wave plate and the polarization beam splitter are in the same plane.
Abstract:
A velocity detecting device includes an image-pattern acquiring unit that includes a laser light source and an area sensor that acquires a one-dimensional or a two-dimensional image. The image-pattern acquiring unit includes a lens between a moving member and the area sensor, irradiates a beam emitted from the laser light source to the moving member to make a scattering light of the moving member scattered from the moving member on the area sensor by using the lens, and acquires an image pattern at a predetermined time interval in association with movement of the moving member. A velocity calculating unit calculates the velocity of the moving member by computing the image pattern acquired by the image-pattern acquiring unit. The lens is a reduced optical system that projects a reduced object onto the area sensor.