Abstract: An improved laser scanner has a scanning lens composed of a single lens element and at least one surface of that lens element is of such a geometry that the curvature in a direction normal to the scanning direction varies gradually in the scanning direction in accordance with the specific deflecting face of an optical deflector. This laser scanner experiences less curvature of the image plane and achieves high resolution.

Abstract: A laser printer can record high definition and high quality images without requiring any increase of electrical and mechanical design precision for increasing a scanning line density thereof. The laser beam is deflected in a primary scanning direction and a subsidiary scanning direction. With such scanning, an artificial scanning line along an edge of a recording image can be established for accurately recording an oblique line, a curved line, a barbel portion of a character, a half-tone image or so forth.

Abstract: An optical information processing apparatus comprising a diffraction grating for producing a zero-order beam which is a beam emitted by a light source and allowed to pass therethrough and two plus and minus first-order sub-beams respectively having positive and negative astigmatisms, radiated in directions at slight angles different from the main beam, wherein said two sub-beams are focused at opposite positions across said main beam, wherein focusing control is performed by a focusing error signal detected from a difference of signal amplitudes obtained from the respective reflected light quantities of said two sub-beams and wherein tracking control is performed by an off-track signal obtained from a signal according to a reflected light quantity of said main beam.

Abstract: An information indicator suitable for information processors such as personal computers, word processors and the like includes a light source, a scattering plate which scatters light from the light source, an indicator plate irradiated with scattered light from the scattering plate, and a prism plate operatively arranged with respect to the scattering plate and the indicator plate and having a prism-like protuberance structure formed at a side thereof. The prism plate is so disposed that the prism-like protuberance structure faces the scattering plate, and the angle 2.theta. constituting the prism-like protuberance structure is defined by the formula, 2.theta.>2/3.times.(.pi./2+2.times.arcsin (n'/n)), in this inequality, n is the refractive index of said prism plate medium, and n' is the refractive index of a material in which the prism plate is arranged.

Abstract: A liquid crystal light valve includes a semiconductor substrate having a region for a plurality of switching elements formed in a matrix form. A first metal layer is formed on the surface of the semiconductor substrate through an insulating layer and divided into a plurality of parts by first slits. A second metal layer is formed on the first metal layer through another insulating layer and divided into a plurality of parts by second slits. A third metal layer is formed on the second metal layer through still another insulating layer and divided into a plurality of parts by third slits. An opposite substrate has an opposite electrode on a surface thereof, disposed so as to be opposite to said third metal layer through an interval on the opposite electrode side. Liquid crystal fills the interval between said opposite electrode and the third metal layer.

Abstract: A light scanning device has a light deflector for deflecting a light beam in a scanning mode which is outputted by a light source, and a scanning lens for compensating or reducing an amount of shift in scanning position which is due to the error of the light deflector. The device also forms an image of the light beam thus deflected. At least one surface of the scanning lens is non-arcuate when a section is taken with a plane which is perpendicular to the surface scanned with the light beam and which contains the normal of the section taken with the surface. Owing to this construction, the light scanning device is suitable for a high precision laser printer.

Abstract: An information recording medium includes an information recording layer on which at least information is to be recorded by irradiating light, and a light transmission restricting layer which has a plurality of nonlinear transmission characteristics or nonlinear reflection characteristics for the intensity of the light irradiated and which has an optical material for restricting the transmission or reflection of the light according to the respective characteristics when the light is irradiated onto the information recording layer. An information recording and reproducing unit uses the information recording medium and includes an information recording position setting unit for deciding a position at which information is to be recorded on the information recording medium by detecting a direction of an easy magnetization axis.

Abstract: The present invention provides a hybrid lens having an axially asymmetrical non-spherical shape, good mass productivity, and excellent shape precision surface precision as well as environment resistant property, and a method for fabricating same, as well as a method and a device for a laser printer using that hybrid lens. In particular, there are disclosed a method, by which, when an axially asymmetrical non-spherical convex lens is formed by the replica method, the shape thereof is transcribed with a high precision, as well as a method and a device for fabricating an axially asymmetrical non-spherical concave lens (female die) serving as an original for the transcription. In a device for fabricating a female die by direct grinding, the positions of a rotation axis of an object to be worked and a rotation axis of a grinding wheel are controlled and it has further a function of correcting mounting errors, when the object to be worked and the grinding wheel are mounted.

Abstract: A recording/reproducing optical head capable of causing a light spot on a photodetector for detecting a focusing error signal to stand still without being affected by variations in wavelength of light used, capable of adjusting a tracking error signal independently of the focusing error signal, and capable of utilizing light having an order of diffraction of -1 for the purpose of detecting a signal, in which a cylindrical lens for generating astigmatism and a diffraction grating made up of two regions different in the direction of diffraction or the angle of diffraction from each other are interposed between a beam splitter and a photodetector, a light beam diffracted from the diffraction grating and including the diffracted light of the zero-th order (that is, light which has passed through the diffraction grating without being deflected) is received by the photodetector, the diffracted light of the zero-th order is used for detecting a focusing error signal according to the astigmatism method, and diffracte

Abstract: An optical beam scanning apparatus comprises means of modulating the optical power of a laser beam produced by a laser beam source, means of shaping the laser beam profile, and means of deflecting and focusing the shaped laser beam on a scanning plane. The optical power of the laser beam is varied in synchronism with the variation of the optical power distribution so that the peak level of optical power of the laser beam is kept constant. The optical power of the laser beam on the photosensitive drum is kept constant irrespective of the beam diameter, and printed dots of intended diameters can be produced, whereby fine multi-tone images can be printed stably.

Abstract: An optical system of an optical neural network model for parallel data processing is disclosed. Taking advantage of the fact that an auto-correlation matrix is symmetric with respect to a main diagonal and the weights for modulating the values of diagonals of the auto-correlation matrix are equal to each other, the configuration of an optical modulation unit is simplified by a one-dimensional modulation array on the one hand, and both positive and negative weights are capable of being computed at the same time on the other hand. In particular, the optical system makes up a second-order neural network exhibiting invariant characteristics against the translation and scale.

Abstract: Disclosed herein is a compact, adjustment-free, unitary optical head wherein diffraction grating made of a birefrigence material and having convexities and concavities of grating grooves so set that the difference of their optical path lengths is some multiples and a half of the wavelength for an ordinary beam and an extraordinary beam, a diffraction grating providing astigmatisms to .+-.1 order beams, a quarter wavelength plate, and other optical components, are interposed between a semiconductor laser and a focussing lens and are stored inside an optical head body filled with a dry nitrogen gas. A focus error detection signal is obtained from the difference of the degrees of modulation of the .+-.1 order reflected beams by pre-wobbled pits, and adjustment of the optical beam can be carried out by driving the body by a two-directional head actuator.

Abstract: A light scanning device has a light deflector for deflecting in a scanning mode a light beam outputted by a light source; and an optical system for image-forming on a scanning medium the light beam deflected by the light deflecting means, with a convergent or divergent light beam in an optical path between the light source and the scanning medium. A plane-parallel plate is moved into and out of the optical path of the convergent or divergent light beam, so as to change a beam spot diameter on the scanning medium.

Abstract: An information recording medium for suppressing the interferences of bits before and after reproduction and improving the optical resolution with saturable absorber 102 disposed adjacent or in an information recording medium layer 103. The recorded information is detected only from a region having a predetermined optical intensity or more of the focused spot so that minute information bits smaller than the optical resolution can be reproduced to improve the recording density of an optical disk drive drastically.

Abstract: In a variable density scanning apparatus, a variable focal distance device is provided in a scanning optical system. This variable focal distance device is formed of a light waveguide having a plurality of electrodes provided of which the lengths along the direction of incident laser beam are decreased or increased with the increase of the distance from the central electrode. The voltage to be applied between the electrodes is controlled in accordance with a desired dot pattern so as to change the refractive index of the light waveguide through which the laser beam is passed, thereby effectively changing the focal distance so that the diameter of the scanning laser beam spot can be changed in one dimension.

Abstract: A laser scanner which includes a rotary polyhedral mirror for scanning a light beam from a laser light source, and an F.theta. lens system which includes first and second lenses through which the light beam is radiated onto a scanning plane. The first lens of the F.theta. lens system is provided on the rotary polyhedral mirror side and is constructed with a joined lens, to increase the degree of design of the first lens. This design freedom for the F.theta. lens system improves the F.theta. characteristic (i.e., characteristic of displacement on a scanning plane), the field curvature characteristic (i.e., characteristic of image defocusing on the scanning plane) and similar problems.

Abstract: In a laser beam scanning apparatus, first and second laser beam emitters emit a laser beam polarized in a specific direction and a laser beam polarized in the direction orthogonal with this specific direction. A prism passes a laser beam emitted from the first laser beam emitter but reflects a laser beam emitted from the second laser beam emitter, and amalgamates two laser beams emitted from the first and second laser beam emitters in almost the same direction. A rotating polygonal mirror and a scanning lens simultaneously scan on a scanned plane two laser beams amalgamated by the prism. A 1/4 wavelength plate is inserted between the rotating polygonal mirror and the prism to change the laser beam from the prism from a linearly polarized state to a circularly polarized state. By the above arrangement, a difference of reflection factors between two laser beams incident to the rotating polygonal mirror can be eliminated so that two uniform laser beams can be scanned at the same time.

Abstract: An optical system of an optical neural network model for parallel data processing is disclosed. Taking advantage of the fact that an auto-correlation matrix is symmetric with respect to a main diagonal and the weights for modulating the values of diagonals of the auto-correlation matrix are equal to each other, the configuration of an optical modulation unit is simplified by a one-dimensional modulation array on the one hand, and both positive and negative weights are capable of being computed at the same time on the other hand. In particular, the optical system makes up a second-order neural network exhibiting invariant characteristics against the translation and scale.

Abstract: In a variable density scanning apparatus, a variable focal distance device is provided in a scanning optical system. This variable focal distance device is formed of a light waveguide having a plurality of electrodes, of which the lengths along the direction of an incident laser beam are decreased or increased with the increase of the distance from the central electrode. The voltage to be applied between the electrodes is controlled in accordance with a desired dot pattern so as to change the refractive index of the light waveguide through which the laser beam is passed, thereby effectively changing the focal distance so that the diameter of the scanning laser beam spot can be changed in one dimension.

Abstract: A beam position control apparatus in which a light beam is led into a light detector from a light generating source through a movable reflector and positioning of the light beam is performed by a servo control circuit for feeding a signal from the light detector back to the movable reflector, comprises: an oscillator for oscillating in response to an initializing signal and moving the movable reflector to move the beam onto the light detector; and a control switch for separating the oscillator and the movable reflector from each other in response to the signal from the light detector, the oscillator and the control switch being arranged in the servo control circuit.