Abstract: A color-converted image forming apparatus is disclosed which permits formation of a color conversion matrix for each of the input images and allows consequent production of an output image which has undergone desired conversion by a relatively simple operation. This apparatus stores image data introduced via an interface 11 in an image memory 13 and, at the same time, analyzes picture elements of an introduced image with a counter 12 to extract a plurality of characteristic magnitudes, and stores the results of the analysis in a characteristic magnitude memory 21. The extracted plurality of characteristic magnitudes are read out together with preset characteristic magnitudes of conversion into a coefficient arithmetic device 22, in which a coefficient for conversion is calculated from the data. The row of coefficients of conversion thus obtained by the calculation are stored in a coefficient row memory 23.

Abstract: A toner mark which is to be sensed by a toner concentration sensor in an electrophotographic printing apparatus includes a rectangular dot pattern where a plurality of toner dot patterns are spaced in a staggered configuration. Each of the toner dot patterns is formed in line which is angled with respect to a width direction of the toner mark. Further, any line along a width direction of the toner mark crosses at least one toner dot pattern.

Abstract: An image reading apparatus which reads document surfaces of open book-like documents placed on a document platen in a face upward condition and detects height of the document to control an image reading operation. An image reader reads the document platen on which the document is placed and outputs image data. A height detector detects height distribution of the document, and a discrimination device determines whether or not abnormalities occur in the height distribution of the document. A memory stores the height distribution of the document, and a update device updates the height distribution of the document stored in the memory when the abnormalities do not occur in the height distribution of the document. A correcting device corrects distortion of the image data caused by the height of the document in accordance with the height distribution of the document stored in the memory.

Abstract: A method for manufacturing a double-sided-multi-layered optical disc. An intermediate substrate having pits on both the major surfaces is previously prepared as well as first and second substrates. The method rotates the first substrate, the intermediate substrate and the second substrate with respect to the common center thereof so as to form unhardened radiation setting resin layers between adjacent substrates so that thicknesses of the unhardened resin layers are adjusted to predetermined values, and then the method irradiates a radiation onto the unhardened resin layer so as to harden the unhardened resin layers to solid resin layers.

Abstract: An optical recording medium of a multi-layer type comprises; a single or plural spacer layers each carrying pits and/or grooves; a single or plural reflective layers layered on the spacer layers; and a silane coupling treatment layer formed between the reflective layer and the spacer layer adjacent to each other.

Abstract: An optical disk allows recording of information at high density and accurate reproduction of such high-density recorded information. The optical disk according to the invention has a shutter layer, formed directly or through an intermediate layer on a substrate, for tightening a light beam to be irradiated to read or write information, the shutter layer containing semiconductor fine particles.

Abstract: An optical disc has a recording film with information recorded thereon, and a photochromic material film provided adjacent the recording film. The photochromic material film is made of a photochromic material. The photochromic material has a first state irradiated with reading light having a first wavelength. In the first state, the transmittance of the material is increased so as to enable reading of the recorded information. The photochromic material further has a second state irradiated with auxiliary light having a second wavelength, where the transmittance becomes low so as to disable the reading of the recorded information.

Abstract: Signal sources are arranged in a matrix form and provide preset analog values. Switching means are connected between signal sources and an analog output terminal having connection paths to the respective signal sources. Latch circuits are respectively provided for switch control circuits for controlling the switching means. Each of the latch circuits latches a control signal from a corresponding one of the switch control circuits and outputs the control signal in response to a preset synchronizing signal to a corresponding one of the switching means. The switching means are simultaneously controlled by output signals of decoders so that a desired analog output is permitted to be derived from the output terminal. The period of the clock signal can be shorten and a switching operation causing variation exceeding a desired variation occurring when the digital signal is changed can be prevented.

Abstract: An optical information record carrier (optical disk, conventionally) has multiple reflective surfaces, each carrying separate information and each readable by an optical beam directed from the same side of the record carrier. The top most reflective surface reflects light of a first waveband and passes light of a second waveband. The next top most reflective layer reflects light within at least part of the second waveband. The record carrier is formed by producing a first reflective layer having a first pit pattern in the surface of a transparent substrate, pressing said first substrate/layer combination to a transparent stamper having a second pit pattern, with a radiation hardening liquid resin therebetween, irradiating the resin by applying radiation to said resin through said stamper, peeling off said stamper, applying a second reflective layer to said hardened resin surface opposite the surface in contact with said first reflective layer, and applying a protective layer to said second reflective layer.

Abstract: An optical information record carrier (optical disk, conventionally) has multiple reflective surfaces, each carrying separate information and each readable by an optical beam directed from the same side of the record carrier. The top most reflective surface reflects light of a first waveband and passes light of a second waveband. The next top most reflective layer reflects light within at least part of the second waveband. The record carrier is formed by producing a first reflective layer having a first pit pattern in the surface of a transparent substrate, pressing said first subtrate/layer combination to a transparent stamper having a second pit pattern, with a radiation hardening liquid resin therebetween, irradiating the resin by applying radiation to said resin through said stamper, peeling off said stamper, applying a second reflective layer to said hardened resin surface opposite the surface in contact with said first reflective layer, and applying a protective layer to said second reflective layer.

Abstract: A color image processing apparatus for converting original image data in the input system into required copy image data based on a lookup table. The apparatus has a memory for storing corrective functions used for the formation of the lookup table, a command generator for generating a command signal for starting the formation of the lookup table and a table forming system for calling the corrective functions from the memory each time the command signal is generated from the command generator and for forming the lookup table based on the corrective functions. For faithful reproduction of the color image of an original image on a copy image, white points and the achromatic axes of the original image conform with those of the copy image and, at the same time, the ranges of color reproduction of the original image conform with the copy image.

Abstract: A plurality of segment groups constituting a D/A converter, and decoders for decoding digital signals and selecting segments constituting the segment groups are arranged on a semiconductor chip. The segments constituting the plurality of segment groups are mingled and two-dimensionally arranged. The positions of the centers of gravity of the respective segment groups are substantially matched with the center of the arranged segments.

Abstract: This invention discloses an analog-to-digital converter. Current supply paths are branched at the current supply terminals from the other current paths so as to be connected exclusively to the analog voltage comparator. And a circuit block of the analog voltage comparator is positioned closer to the current supply terminals than the other circuit block of DA converter, sequential comparison register, etc.

Abstract: To compensate for an offset of an A/D converter, a predetermined reference signal is supplied to the A/D converter. Based on the output signal of the A/D converter, the amount of the offset for this converter is acquired. A multiplexer outputs a compensation signal which serves to cancel out the acquired offset amount, the output of this multiplexer is subjected to analog addition to the analog input signal, and the offset of this A/D converter is compensated for at the input stage.

Abstract: A signal interference prevention wiring is disposed between two wirings which are arranged in parallel for transmitting a signal, and the signal interference prevention wiring is held at a constant potential.

Abstract: A method for reproduction of a multi-tone color image by combination of chromatic inks of cyan, magenta and yellow together with an achromatic ink of black. In the region of lower tone levels than a prescribed value, the image is formed by the complete under color removal, namely, by the sole use of the achromatic ink. In the region of higher tone levels than the prescribed value, the reproduction of the image is attained by performing the under color removal at a ratio of decrease relative to the rise of the tone levels, namely by causing the chromatic inks to overlap the achromatic ink.

Abstract: A successive approximation type A/D converter of the present invention has a capacitor having a predetermined capacitance value and arranged between an input terminal of a voltage comparator and a fixed potential terminal having a predetermined potential. According to the successive approximation type A/D converter of the present invention, the capacitor arranged between the input terminal of the voltage comparator and the fixed potential terminal having the predetermined potential prevents a potential at the input node of the voltage comparator from being greatly changed to exceed a power source voltage range due the influences of a local D/A converter when the sample mode is switched to the approximation mode. Therefore, the leakage of charges stored in the input side of the voltage comparator can be prevented. Accordingly, even if the amplitude of an analog input voltage is equal to the amplitude of the power source voltage, high-precision A/D conversion can still be performed.

Abstract: A level shift circuit is made up of a capacitor, a MOS inverter, and a bias circuit for applying a bias voltage to an input node of the MOS inverter. A first electrode of the capacitor is connected to an output stage of an ECL circuit, while a second electrode to the input node of the MOS inverter. The output node of the MOS inverter is coupled with an input stage of a CMOS circuit. An output signal of the ECL circuit is capacitively coupled with the input node of the MOS inverter so that it is superposed onto a bias voltage being supplied from the bias circuit. A level of this signal is shifted to a CMOS logic level by the MOS inverter, and then applied to the input stage of the CMOS circuit.

Abstract: An A/D converter of this invention includes a first A/D converter for A/D-converting the input signal and determining upper bits of the n-bit binary code, first and second sample-hold circuits, which are alternately switched each time the first A/D converter samples the analog input signal, for sampling and holding the analog input signal, in synchronism with a sampling timing of the first A/D converter, and a second A/D converter. The second A/D converter is constituted by a reference voltage generator for generating reference voltages, based on contents of the binary code obtained by the first A/D converter, a voltage comparator for comparing the reference voltage with a voltage value of the analog input signal held in one of the first and second sample-hold circuits, which sample and hold the analog input signal corresponding to the binary code, and an encoder for encoding a comparison result output from the voltage comparator and determining lower bits of the n bits.

Abstract: A digital-to-analog converter includes a group of resistors serially connected between a power source potential supply terminal and a reference potential supply terminal. First group switches are connected between a first circuit point and given serial connection nodes of the resistor group, and between the first circuit point and the reference potential supply terminal. Each of these switches is controlled so as to be selectively turned on according to the result obtained from decoding upper bits of a digital signal. Further, second group switches are connected between a second circuit point and other serial connection nodes of the resistor group, and between the second circuit point and the reference potential supply terminal. Each of these switches is controlled so as to be selectively turned on according to the result obtained from decoding lower bits of the digital signal.