Abstract: A compact internal focus objective lens system utilized in an astronomical telescope, tenestrical telescope, photo lens or the like has a superior ability to compose images when focusing on close or near objects. The lens system includes, in order from the object side, a first lens group G1 with a positive refractory power and a second lens group G2 with a negative refractory power. The first lens group G1 includes a composite lens L1 with a negative lens L11 and a positive lens L12 and a single lens L2 with a positive refractory power. The second lens group G2 has a composite lens L3 that has an overall negative refractory power. The second lens group G2 is moved along the optical axis for focusing. The objective lens satisfies the following conditions, thus permitting the compact internal focus objective lens system to clearly compose images, when focusing on close or near objects:0.3<f1/F<0.6-0.5<f2/F<-0.20.15<r4/F<0.35-1.5<(r6+r8)/(r6-r8)<1.50.15<r2/F<0.440<.nu.

Abstract: A wide-angle zoom lens system includes a first lens group having a positive refractive power and a second lens group having a negative refractive power and spaced from the first lens group at a first distance, the first distance being variable during zooming. The first lens group includes a first lens having a positive refractive power and a convex surface toward an object, a second lens having a negative refractive power and concave surfaces, a third lens having a positive refractive power and convex surfaces, a fourth lens having a negative refractive power and convex surfaces, a fifth lens having a negative refractive power and a concave surface toward the object, and a sixth lens having a positive refractive power and one of convex and meniscus surfaces. The second lens group includes a seventh lens having a positive refractive power and a concave surface toward the object and at least one element of a negative refractive power lens. The zoom lens system having the following characteristics:0.5<f.sub.

Abstract: An exposure apparatus for transferring a pattern formed on a mask to a photosensitive substrate is provided with an illumination optical system for illuminating a local area on the mask with a light beam, a projection optical system for projecting the pattern of the mask to the photosensitive substrate and a relative scanning device for relatively scanning the mask and the photosensitive substrate in a perpendicular direction to the optical axis of the projection optical system so as to transfer the pattern of the mask to the photosensitive substrate.

Abstract: A compact objective lens with a diaphragm arranged behind the lens system suitable for use in very compact photographic cameras. The objective lens comprises a plurality of components arranged in a triplet or a triplet type configuration and is capable of covering at least a 55 degree field of view.

Abstract: In a self-supporting beam-splitter (1), in particular for use in an FTIR-spectrometer for the far-infrared region, with an optical thickness on the order of the interesting wavelength region, the foil beam-splitter (1) consists of an undoped semi-conducter material or carbon which is transparent in the far-infrared, and is preferentially made from thin silicon sheets or diamond foil in the thickness region between 2 .mu.m and 125 .mu.m. In this fashion, an extremely high efficiency for the beam-splitter is achieved, whereby little or no resonant absorption takes place due to the beam-splitter in the interesting wavelength region.

Abstract: An image reading device (image scanner) includes a resolution changing device that changes a resolution of the image signals output by a photoelectric sensor device by changing a primary scanning direction aperture size, a secondary scanning direction aperture size, or both, of the photoelectric sensor device. In order to change a resolution in the secondary scanning direction, the secondary scanning direction aperture size is changed, for example, by a control device that controls a drive velocity of a drive device that drives the photoelectric sensor device in the secondary scanning direction relative to an original document. Alternatively, the control device can control a duration of an integral time of the photoelectric sensor device during which the photoelectric sensor elements of the photoelectric sensor device collect light from the original document in order to vary the secondary scanning direction aperture size.

Abstract: A planar parallel plate direct vision prism including two glasses for dispersing light as a function of color is disclosed. Also disclosed is an optical system which includes a first optical assembly having two planar parallel plate direct vision prisms for dispersing light as a function of color. The degree and orientation of the light dispersed is controlled by rotating the two prisms of the first assembly in relation to each other and together in unison. A fiber optic bundle transmits the dispersed light and a second optical assembly having two planar parallel plate direct vision prisms recombines the dispersed light emerging from the fiber optic bundle. The degree and orientation of the light recombined is controlled by rotating the prisms of the second optical assembly in relation to each other and together in unison.

Abstract: A removable coupler including first and second ends, the first end connected to an electrical connector and the second end attached to an optical connector. The optical connector includes a housing containing electronics therein to convert electrical signals to signals which are transmitted optically. The housing may also or alternatively include electronics therein to convert signals received optically to electrical signals.

Abstract: A varifocal lens whose variable focal length can be controlled by, for example, an electric signal, and suitable for use in bar code readers, etc. A varifocal lens comprises a first pressure chamber defined between a glass substrate and a transparent elastic film. The transparent elastic film is faced to the surface of the planar glass substrate having parallel surfaces with a spacer incorporated therebetween to provide the first pressure chamber. A pump is provided adjacent to the first pressure chamber via a communicating path for charging an operating liquid to the first pressure chamber from a second pressure chamber of the pump by electrically deforming the transparent elastic film to form a lens having a variable focal length. The transparent elastic film has a film thickness distribution as such to provide a spherical plane in the central portion thereof and a third order curved surface in the periphery thereof.

Abstract: A compact objective lens system with a diaphragm arranged in front of or preferably behind the lens system and suitable for use in compact photographic cameras. The objective lens comprises a plurality of components arranged in a triplet-type configuration that are capable of covering at least a 55 degree field of view and utilizes the locations of aperture stop, the lens bendings, and the size of lens elements, clear apertures of the lens element surfaces to enhance the lens system performance and to eliminate stray light problems.

Abstract: A variable power optical system for a copying machine includes a first lens group having a negative power, a second lens group having a positive power, and a third lens group having a negative power. All three lens groups are moved to vary distances D.sub.1 and D.sub.2 between the first and second lens groups and between the second and third lens groups, to thereby vary the magnification in a range from an actual size to an enlargement range, while maintaining a constant distance between an object and an object image. In the range from the actual size to the enlargement range, the optical system satisfies the relationship defined by 0.60<.vertline.(D.sub.m1 -D.sub.e1)/(D.sub.m2 -D.sub.e2).vertline.<0.85, wherein "D.sub.mi " designates a value of D.sub.i (i=1,2) at a maximum magnification, and "D.sub.ei " designates a value of D.sub.i (i=1,2) at an actual size, respectively.

Abstract: A focus detection apparatus adapted to reform images of light fluxes that pass through differing regions of a photographic lens into a pair of images on light receiving element arrays by using, for each pair of images, a field mask, a field lens, a pair of re-imaging lenses and an aperture mask having a pair of aperture openings provided in the vicinity of the pair of re-imaging lenses. The focus detection apparatus has multiple focus detection blocks that detect the focus condition of the photographic lens from positions relative to the pairs of images. The focus detection apparatus is further adapted to detect the focus condition of multiple areas on a focal plane. The focus detection apparatus includes a deflection mirror positioned between the field lens and the pair of re-imaging lenses. The deflection mirror causes the light fluxes to be deflected at nearly right angles for focus detection.

Abstract: A photo interrupter includes a lead frame having a light-emitting element and a light-receiving element provided thereon and having a lead pattern for connecting input/output terminals of both the light-emitting element and said light-receiving element to the outside at a converged connector-jointing portion. Both the light-emitting element and the light-receiving element are provided on the common lead frame which is connected directly to a connector for connecting to the outside. A casing for holding the light-sensing parts is composed of a thermoplastic resin and provided with melt pins joining the connector and the lead frame to the casing.

Abstract: A method and apparatus for detecting the skew angle of a document image. Skew angle determination is performed by the steps of determining a set of sampling points from an input document image and processing X and Y coordinates of the sampling points in order to calculate a regression coefficient of the sampling points. The skew angle of the document is determined using the regression coefficient. To evaluate a calculated skew angle which corresponds to the regression coefficient, a correlation coefficient is calculated and evaluated. As coordinates of sampling points are obtained for a plurality of sets of data corresponding to different ruled lines or lines of characters, a histogram may be used to determine the most probable skew angle.

Abstract: A zoom lens system includes at least three lens groups including a positive first lens group, a positive second lens group, and a negative third lens group, in this order from an object side. The first, second and third lens groups are all moved toward the object side during zooming from a wide angle extremity to a telephoto extremity so that a distance between the first and second lens groups increases and a distance between the second and third lens groups decreases. The zoom lens system satisfies the formulae:0.7<f.sub.L /f.sub.1 <1.4;and2.0<m.sub.3L <2.8,wherein "f.sub.L " designates the focal length of a whole lens system at the telephoto extremity, "f.sub.1 " designates the focal length of the first lens group, and "m.sub.3L " designates the lateral magnification of the third lens group at the telephoto extremity.

Abstract: An optical element driving mechanism is disclosed wherein an electromagnetic motor positions an optical element such that a laser beam passing through the optical element is focused onto an optical disk media. The optical element can be translated in two axes by energizing coils suspended within stationary magnetic fields produced by permanent magnets. The magnitude and direction of displacement is controlled by the current passing through the coils. A two axis electro-optical position sensing apparatus for determining the position of the optical element is embedded within the driving mechanism. The position sensing apparatus detects the relative position of the optical element in two axes by imaging a light emitting diode onto a four element photodetector.

Abstract: An optocoupler package (40) has two pre-molded thermoplastic halves (42, 54); one containing the emitter (16) and the other containing the detector (18). The detector half (54) has a well (56) where the detector (54) is located. The well (56) is filled with silicon die coat gel (24). The emitter half (42) has a similar well (48) containing the emitter. Surrounding the well (48) of the emitter half is a protruding wall (50) with relief vents (52). The wall (50) is configured to fit into the perimeter of the well (56) of the detector package half (54). When the package (40) is assembled, the protruding wall (50) of the emitter half (42) is inserted into the well (56) of the detector package half (54), thereby displacing the gel (24) so as to completely fill the internal chamber (66) and spill into the relief vents (52).

Abstract: A scanning probe microscope having a probe for scanning a sample, a piezoelectric unit finely movable in the X, Y and Z directions, and a probe control unit for controlling a fine movement amount of the piezoelectric unit in the Z direction in accordance with a detected interaction between the sample and the probe. A driving unit applies a continuously changing voltage to the piezoelectric unit to drive the piezoelectric unit in one of an X and Y direction to scan along a scan line, a displacement detection unit detects the displacement of the piezoelectric unit along the scan line, and a matching detection unit outputs a coincidence detection signal when the detected displacement of the piezoelectric unit along the scan line coincides with target displacement values corresponding to desired measurement points.

Abstract: The pulsed optical rotary encoder digitally samples the operation of the optical rotary encoder to obtain the same information that is obtained by the use of the continuously active light-emitting devices but in a much more energy-efficient manner. In particular, the light-emitting devices are pulsed into operation for a short duration and at a frequent rate. The signals produced by the light detectors associated with the light-emitting devices are sampled at a predetermined time after firing the light-emitting devices to obtain the data necessary to determine the rotation of the coding disk.

Abstract: The light information device of the invention includes a semiconductor having a photoconductive effect or a photovoltaic effect. In the light information device, a photoconductivity and a dark conductivity of the semiconductor are varied by an aging process using an external stimulus, and the photoconductivity and the dark conductivity after the aging process have values which are equal to or lower than 20% of respective initial values thereof before the aging process.