Abstract: A method of making a micromirror unit is provided. In accordance with the method, a micromirror unit is made from a material substrate having a multi-layer structure composed of silicon layers and at least one intermediate layer. The resulting micromirror unit includes a mirror forming base, a frame and a torsion bar. The method includes the following steps. First, a pre-torsion bar is formed by subjecting one of the silicon layers to etching. The obtained pre-torsion bar is rendered smaller in thickness than the mirror forming base and is held in contact with the intermediate layer. Then, the desired torsion bar is obtained by removing the intermediate layer contacting with the pre-torsion bar.

Abstract: A method of making a micromirror unit is provided. In accordance with the method, a micromirror unit is made from a material substrate having a multi-layer structure composed of silicon layers and at least one intermediate layer. The resulting micromirror unit includes a mirror forming base, a frame and a torsion bar. The method includes the following steps. First, a pre-torsion bar is formed by subjecting one of the silicon layers to etching. The obtained pre-torsion bar is rendered smaller in thickness than the mirror forming base and is held in contact with the intermediate layer. Then, the desired torsion bar is obtained by removing the intermediate layer contacting with the pre-torsion bar.

Abstract: A plurality of micromirror chips are collectively made from a common substrate. Each of the micromirror chips is formed with a micromirror unit including a frame, a mirror-forming portion separate from the frame via spaces, and torsion bars connecting the mirror-forming portion to the frame. The common substrate is subjected to etching to provide the spaces and make division grooves for dividing the common substrate into the individual micromirror chips. The etching for the spaces and the etching for the division grooves are performed in parallel with each other.

Abstract: A micro mirror unit includes a moving part carrying a mirror portion, a frame and torsion bars connecting the moving part to the frame. The moving part, the frame and the torsion bars are formed integral from a material substrate. The frame includes a portion thicker than the moving part.

Abstract: A micro mirror unit includes a micro mirror substrate, a wiring substrate and an electroconductive spacer disposed between these substrates. The micro mirror substrate includes a moving part, a frame and torsion bars connecting the moving part to the frame. The moving part is provided with a mirror-formed portion. The wiring substrate is formed with a wiring pattern. The electroconductive spacer electrically connects the frame to the wiring pattern, while also providing a space between the micro mirror substrate and the wiring substrate.

Abstract: A method of making a micromirror unit is provided. In accordance with the method, a micromirror unit is made from a material substrate having a multi-layer structure composed of silicon layers and at least one intermediate layer. The resulting micromirror unit includes a mirror forming base, a frame and a torsion bar. The method includes the following steps. First, a pre-torsion bar is formed by subjecting one of the silicon layers to etching. The obtained pre-torsion bar is rendered smaller in thickness than the mirror forming base and is held in contact with the intermediate layer. Then, the desired torsion bar is obtained by removing the intermediate layer contacting with the pre-torsion bar.

Abstract: A micromirror unit is provided which includes a frame, a mirror forming base upon which a mirror surface is formed, and a torsion connector which includes a first end connected to the mirror forming base and a second end connected to the frame. The torsion connector defines a rotation axis about which the mirror forming base is rotated relative to the frame. The torsion connector has a width measured in a direction which is parallel to the mirror surface and perpendicular to the rotation axis. The width of the torsion connector is relatively great at the first end. The width becomes gradually smaller from the first end toward the second end.

Abstract: A method is provided for making a micromirror unit which includes a frame, a mirror forming base, and bridges connecting the frame to the mirror forming base. The method includes the following steps. First, a first mask pattern is formed on a substrate for masking portions of the substrate which are processed into the frame and the mirror forming base. Then, a second mask pattern is formed on the substrate for masking portions of the substrate which are processed into the bridges. Then, the substrate is subjected to a first etching process with the first and the second mask patterns present as masking means. Then, the second mask pattern is removed selectively. Then, the substrate is subjected to a second etching process with the first mask pattern present as masking means. Finally, the first mask pattern is removed.

Abstract: A method of making a galvano-mirror is provided. It includes the following steps. First, a first material substrate formed with a plurality of mirror plate regions is prepared. The mirror plate regions correspond in arrangement to the mirror plate of the galvano-mirror. Then, a second material substrate formed with a plurality of driver plate regions is prepared. The driver plate regions correspond in arrangement to the driver plate of the galvano-mirror. Then, the first and the second material substrates are attached to each other so that each of the mirror plate regions faces a relevant one of the driver plate regions. Finally, the attached first and second material substrates are divided into individual gaslvano-mirrors.

Abstract: An optical device includes a plurality of lens plates spaced at specific intervals. At least one of the lens plates is provided with a lens array on at least one of its front and rear faces. The lens array is composed of a plurality of closely arranged lenses of a specific configuration. The lens array has at least one groove having a V-shaped cross-sectional configuration at a joint of adjacent lenses in at least one part of the lens array.

Abstract: An optical device comprising an image formation unit consisting of a plurality of lens substrates each formed on the front and rear faces thereof with lens arrays and a display unit disposed on an object surface with respect to the image formation unit and displaying an image to be projected by the image formation unit, characterized in that the lens array is a cylindrical lens array and the generating line of a cylindrical array formed on the front face and the generating line of a cylindrical array formed on the rear face cross each other. The lens substrate formed on the front and rear faces thereof with cylindrical lens array is used to provide a small lightweight optical device of a full-size or magnified image system.

Abstract: A method of making a galvano-mirror is provided. It includes the following steps. First, a first material substrate formed with a plurality of mirror plate regions is prepared. The mirror plate regions correspond in arrangement to the mirror plate of the galvano-mirror. Then, a second material substrate formed with a plurality of driver plate regions is prepared. The driver plate regions correspond in arrangement to the driver plate of the galvano-mirror. Then, the first and the second material substrates are attached to each other so that each of the mirror plate regions faces a relevant one of the driver plate regions. Finally, the attached first and second material substrates are divided into individual gaslvano-mirrors.

Abstract: An optical device includes a plurality of lens plates spaced at specific intervals. At least one of the lens plates is provided with a lens array on at least one of its front and rear faces. The lens array is composed of a plurality of closely arranged lenses of a specific configuration. The lens array has at least one groove having a V-shaped cross-sectional configuration at a joint of adjacent lenses in at least one part of the lens array.

Abstract: An optical device comprising an image formation unit consisting of a plurality of lens substrates each formed on the front and rear faces thereof with lens arrays and a display unit disposed on an object surface with respect to the image formation unit and displaying an image to be projected by the image formation unit, characterized in that the lens array is a cylindrical lens array and the generating line of a cylindrical array formed on the front face and the generating line of a cylindrical array formed on the rear face cross each other. The lens substrate formed on the front and rear faces thereof with cylindrical lens array is used to provide a small lightweight optical device of a full-size or magnified image system.

Abstract: An image reader apparatus includes an illuminating element to illuminate a document face to be read, an optical element to form an image of the document face illuminated by the illuminating element, an image sensor to photoelectrically convert the image formed by light passing through the optical element, and a running roller rotating in contact with the document face, wherein a horizontal distance between a document contact portion of the running roller where the running roller contacts the document and a center of imaging of the optical element is shorter than or equal to 10 mm.

Abstract: An optical device including an optical imaging system for forming a real image of an object on a light-receiving surface, the optical imaging system including first and second cylindrical lenses and first and second intermediate lenses, each of the intermediate lenses being composed of a plurality of lens elements arrayed in a line, the first and second cylindrical lenses being opposed to each other so that generatrices thereof are parallel to each other, the first and second intermediate lenses being arranged between the first and second cylindrical lenses in a direction of the generatrices so that a light beam emanated from the object is condensed onto the light-receiving surface through the first cylindrical lens, the first intermediate lens, the second intermediate lens and the second cylindrical lens, wherein each of the lens elements is formed of a one-dimensional binary lens having a light-condensing property only in the direction of the generatrices, whereby a real image by the first and second cylind

Abstract: An optical apparatus having a first lens array consisted of a plurality of lens forming reduced image in reversed orientation, a second lens array consisted of a plurality of lens arranged at corresponding positions to the lens of the first lens array and forming erected equal magnification image from the reduced image by expanding the reduced image in the given magnification, and one or more light shielding film arranged between the first lens array and the second lens array and having through openings for passing light discharged from respective lens of the first lens array at positions corresponding to respective lens of the first lens array in opposition to respective lens for passing discharged light from respective lens of the first lens array.

Abstract: An optical apparatus having a first lens array consisted of a plurality of lens forming reduced image in reversed orientation, a second lens array consisted of a plurality of lens arranged at corresponding positions to the lens of the first lens array and forming erected equal magnification image from the reduced image by expanding the reduced image in the given magnification, and one or more light shielding film arranged between the first lens array and the second lens array and having through openings for passing light discharged from respective lens of the first lens array at positions corresponding to respective lens of the first lens array in opposition to respective lens for passing discharged light from respective lens of the first lens array.

Abstract: A method for fabricating an SHG device by forming an inversion region having a first direction of polarization selectively in a ferroelectric substrate that has a second, opposite direction of polarization. A proton exchange process exchanges cations in the ferroelectric substrate with protons, selectively in correspondence to each portion of the substrate in which an inversion region is to be formed. Electrodes are provided on upper and lower major surfaces of the ferroelectric substrate, and the inversion region is selectively grown in a direction perpendicular to the upper major surface of the ferroelectric substrate while applying a d.c. voltage to the electrode on the upper major surface of the ferroelectric substrate thereby to induce an electric field acting in a direction coincident with the direction of said first polarization in said ferroelectric substrate.

Abstract: A waveguide type second-harmonic generation element includes a substrate made of LiTaO.sub.3, approximately parallel domain inversion regions formed on the substrate and extending in a first direction, where the domain inversion regions have a first depth into the substrate, approximately parallel domain non-inversion regions formed on the substrate and extending in the first direction, where the domain inversion region and the domain non-inversion regions alternately occur on the substrate, and an optical waveguide formed on the substrate and traversing the domain inversion regions and the domain non-inversion regions, where the optical waveguide has a second depth and extends in a second direction which is approximately perpendicular to the first direction.