Abstract: A multi-bit D/A converter which improves the linearity of an analog output relative to a digital input is provided. A switch control circuit (1) turns on D some of a plurality of switches (S1 to SM) which are arranged in ascending order starting with a switch determined by a start position determination circuit (3) and turns off the remaining switches, the number of switches turned on being dependent on a digital signal (DIG). The start position determination circuit (3) sequentially changes the switches (S1, S3, S5, . . . ) serving as a selection start position to determine the selection start position for each input of the digital signal (DIG) provided in synchronism with a clock signal (CLK).

Abstract: An image recording apparatus has an array light source having a plurality of light-emitting elements arrayed in a predetermined density; a photosensitive member exposed to light beams emitted from the plural light-emitting elements so that images are recorded by fixing a traveling path of the light beams from the plural light-emitting elements to the photosensitive member and by moving the photosensitive member relative to the array light source; a beam-converging unit which intercrosses a bundle of the light beams emitted from the light-emitting elements onto a beam-conversion point; and an focusing unit disposed between the beam-converging unit and the photosensitive member, which images the light beams emitted from the plural of light-emitting elements and intercrossed by the beam-converging unit onto the photosensitive member.

Abstract: An object is to obtain a voltage comparator capable of high-accuracy voltage comparison. An input voltage (VIN) and a reference voltage (VREF) are connected to one electrode of a capacitor (C1) through switches (S1) and (S2), respectively. The other electrode of the capacitor (C1) is connected to the input portion of an inverter (INV1). The output portion of the inverter (INV1) is connected to the input portion of an inverter (INV3) and is also fed back to the input through a switch (S3). An inverter (INV11) is further connected in parallel with the inverter (INV1), wherein the input/output characteristics of the inverters (INV1, INV3 and INV11) are set equal.

Abstract: A multibeam laser recording apparatus is so arranged as to include a scanning line interval detecting mechanism located at a position equivalent to the surface of the image carrier, for detecting scanning line intervals of the plural laser beams scanned on the surface of the image carrier, and a controller for controlling the scanning line intervals of the plural laser beams scanned on the image carrier based upon an output derived from the scanning line interval detecting mechanism in such a manner that the scanning line intervals are kept constant.

Abstract: A majority logic circuit is supplied with output values of adjacent three comparators. The majority logic circuit outputs, as an output signal, the supplied three output values including at least two equal output values. Inverter circuits and AND circuits produce and output a read signal of an encoder which is a logical product between the output signal and an inverted signal of the output signal.

Abstract: In a subranging type A/D converter apparatus, the A/D converter apparatus executes A/D conversion by separating the A/D conversion into an A/D conversion of high-order bits and an A/D conversion of low-order bits in two steps, while feeding back a first control signal for executing the A/D conversion of the low-order bits according to results of the A/D conversion of the high-order bits. A digital logic circuit section executes decision of the A/D conversion to a control terminal of a switch group of a reference voltage generator circuit for generating a plurality of reference voltages via a feedback line provided in a plurality of voltage comparators provided with a plurality of differential amplifiers. Each of the differential amplifiers includes a plurality of transistors each for executing differential amplification. The plurality of differential amplifier transistors are arranged so as to be symmetrical with respect to the feedback line provided in each of the differential amplifiers.

Abstract: An optical scanning device having a scanning speed which can be used in a laser beam printer, a digital copier, a facsimile apparatus or the like, an optical scanning method using the optical scanning device, and an image forming apparatus using the optical scanning device are disclosed. The optical scanning device comprising: a light source for emitting a laser beam having a constant divergent angle; a thin film waveguide; means for coupling the laser beam to said thin film waveguide; and a comb-like electrode for exciting a surface acoustic wave of a high frequency sweep signal so that the laser beam is deflected to be output as parallel rays.

Abstract: A semiconductor laser array emits a plurality of laser beams. A polygon mirror deflects the plurality of laser beams together. A prism type reflector separates the deflected laser beams to different directions that are generally along an arrangement direction of a plurality of photoreceptors. The separated laser beams are input to the respective photoreceptors through mirrors and cylindrical lenses.

Abstract: An image writing apparatus has improved performance of image reproduction based on a multi-beam scanning optical system, in which the number of laser beams n and the spacing of scanning lines p meet the condition: 1/(n.multidot.p).gtoreq.4 line pairs per millimeter. The optical system is further designed such that the number of deflection planes q of the deflector, a natural number m, where the period of repetitive patterns of image in the slow scan direction is equal to p multiplied by m, and the least common multiple E of m and n, or the least common multiple G of m, n and q meet the condition:1/(E.multidot.p).gtoreq.4 or 1/(G.multidot.p).gtoreq.4 line pairs per millimeter.

Abstract: An information recording device having a light source unit including a plurality of laser light sources which are substantially linearly arrayed and independently driven, a deflecting unit for periodically deflecting a plurality of beams of laser light emitted from the light source unit in a direction crossing that of an array of the beams, and an image forming optical system for focusing the plurality of laser beams from the deflecting unit on a photoreceptor. In the information recording device, optical units for reducing divergence of the laser beams are provided in connection with the laser light sources of the light source unit.

Abstract: A light intensity control device includes light intensity balancing means for balancing the light intensities of the laser beams from the light emitting elements of the laser light source, and simultaneous operating means for simultaneously operating the light emitting elements of the laser light source, wherein the sum of the light intensities of the laser beams from the light emitting elements simultaneously operated by the simultaneous operating means is detected by single detecting means at one time, and is controlled according to the detection output from the detecting means. Accordingly, it is possible to reduce the time required to perform the control of light intensities of laser beams from semiconductor laser elements when the number of the laser beams is increased, thereby more greatly exhibiting the effect of high-speed operation obtained by the increase in number of the laser beams.

Abstract: An A/D converter block A/D1 converts an analog input signal Vin to a digital signal and outputs its D/A output. First SH/SUBT7, 8 sample the signal Vin and a voltage VRM at the same timing with said A/D conversion and output the results of subtraction of the respective sampling values and the D/A output during holding, respectively. The both results of subtraction are several tens mV and there is no need of taking account of the linearity of a differential amplifier DIFF11. During the sampling, a circuit SHR1 outputs the differential voltages between each reference tap voltage taken out from specific 2 points of the ladder-type resistor in the A/D converter block A/D1 and the voltage VRM while a differential amplifier DIFF12 applies the reference voltages to the next A/D converter block A/D2. Such operations are performed in each stage. Thus, it becomes possible to make any S/H circuit and amplifier of excellent linearity in the first stage unnecessary to reduce the electric power consumption.

Abstract: An information recording device having a light source unit including a plurality of laser light sources which are substantially linearly arrayed and independently driven, a deflecting unit for periodically deflecting a plurality of beams of laser light emitted from the light source unit in a direction crossing that of an array of the beams, and an image forming optical system for focusing the plurality of laser beams from the deflecting unit on a photoreceptor. In the information recording device, optical units for reducing divergence of the laser beams are provided in connection with the laser light sources of the light source unit.

Abstract: A plasma processing apparatus for performing plasma process on a semiconductor or the like draws an electron beam from an electron source plasma and, after acceleration, introduces the electron beam into a reaction chamber where a requisite gas is supplied for performing plasma process on the semiconductor wafer. At least one pair of magnets are provided in the chamber with an electron beam path created therebetween. The electron beam is formed into a sheet-like configuration through a magnetic field created by the at least one pair of magnets. The at least one pair of magnets are positioned in an opposed relation to allow the semiconductor wafer to be subjected at a uniform rate to plasma process.

Abstract: A color image forming apparatus for forming a color image by transferring images of different colors on a recording medium in a multi-transfer mode. The color image forming apparatus includes a plurality of image forming units for successively forming color images of different colors according to image information, a transfer/transport unit for transporting different color images formed by the image forming units in a state that the color images are successively transferred thereon, a detecting unit for detecting patterns used for detecting an out-of-registration of the color images formed on the transfer/transport unit by the image forming units, and a correcting unit for correcting positions of the color images to be transferred on the transfer/transport unit according to data signal output from the detecting unit.

Abstract: A differential amplifier circuit is obtained in which an operating power source voltage is suppressed to a minimum necessary level. The differential amplifier circuit includes a bias circuit having a differential amplifier with NMOS transistors (11A, 11B, 12A and 12B) and PMOS transistors (13A and 13B). Sources of NMOS transistors (11A)and (11B) are commonly grounded. A bias voltage (VB1) is supplied to gates of the NMOS transistors (11A) and (11B). Drains of the NMOS transistors (11A) and (11B) are connected to sources of NMOS transistors (12A) and (12B), respectively. A gate and a drain of the NMOS transistor (12A) are short-circuited to each other with the drain connected to a drain of a PMOS transistor (13A). A bias voltage (VB4) is applied to a gate of the NMOS transistor (12B). A drain of the NMOS transistor (12B) is connected to a drain of the PMOS transistor (13B) whose gate and drain are shared by each other.

Abstract: The inner surface of an outer cylinder is made an outer cylinder raceway having a simple circular sectional configuration having a radius of curvature. On the outer circumference of an inner cylinder, a plurality of grooves having the radius of curvatures dimensioned equally to the aforesaid radius of curvature are arranged extendedly at the same pitch. The outer circumference of barrel shaped rollers inserted between the grooves and the inner surface of the outer cylinder is dimensioned equally to the aforesaid radius of curvature. The barrel shaped rollers and the inner and outer raceways constitute linear contacts, thus enhancing the ability of the load resistance to make it possible to prevent the peeling off, cracking, and other damages from taking place by the heavy load to be applied.

Abstract: A multi-beam scan optical system for writing image information. The system includes a laser array having a plurality of laser diodes, a collimate lens for collimating a plurality of laser beams output from the laser diodes, and an optical member for focusing the collimated laser beams. An aperture is disposed at a position where optical axes of the plurality of laser beams cross an optical axis of the optical member. The system includes a relationship between a distance r.sub.1 of separation of the laser diodes, a divergence angle .theta., of each of the laser beams, a wavelength .lambda. of each of the laser beams, and an interlace scanning period i, wherein these values satisfy the relation: ##EQU1## where K is a number in a range from 1.0 to 1.8. The value .alpha. depends on the diameter of the aperture as viewed in a subsidiary scan direction and satisfies the relation:d.sub.2 =(4.alpha./.pi.)(.lambda.f.sub.2 /D)where .pi. is a circular constant, f.sub.

Abstract: A color registration error detecting method for repeatedly forming a plurality of registration error detection patterns of different colors on an image carrier, detecting the registration error detection patterns, and detecting a color registration error from detection signals of the patterns. In this method, a sampling length and a sampling frequency for detection of the registration error detection patterns are set so as to satisfy the conditions of (1) the sampling length is to be approximated to a wavelength of a vibrational component be read with a registration error component by registration error detecting means or to an integer multiple of the wavelength; (2) the sampling length is to be set as large as possible; and (3) the sampling frequency and an integer multiple thereof are to be separated as far as possible from a frequency of the vibrational component.

Abstract: A method of measuring physical strength of a subject and an apparatus therefor in which the maximum oxygen uptake based on 75% of the estimated maximum heart rate as a reference is estimated to thereby evaluate physical strength based on the oxygen uptake during exercise. The oxygen uptake is used as an index for evaluating physical strength, and 2@75% HRmax, which is oxygen uptake measured at 75% of estimated maximum heart rate, is used as a reference so that comparison can be made safely with a measured value even for middle and high ages. The apparatus is provided with a load device which can give a ramp load to a subject (e.g.