Patent application number | Description | Published |
20080252787 | ANALOG PROCESSING CIRCUIT, ANALOG INTEGRATED CIRCUIT DEVICE, IMAGE READING DEVICE, AND IMAGE FORMING APPARATUS - A first clamping unit clamps a base voltage of an input image signal to a predetermined reference voltage. A sampling-and-holding unit samples and holds the image signal after clamping or a reference signal that becomes the base voltage of the image signal. An amplifying unit amplifies the image signal sampled and held by the sampling-and-holding unit. An analog-to-digital converting unit converts the image signal after amplification into a digital image signal. A second clamping unit clamps the reference signal to a predetermined voltage. | 10-16-2008 |
20100027061 | IMAGE READING DEVICE AND IMAGE FORMING APPARATUS - An image reading device includes a charge-coupled device that generates and outputs an image signal, a timing generator that outputs a frequency-modulated clock, a modulation signal detector that detects a modulation signal being a signal corresponding to a change in frequency of the clock, an amplitude controller that controls an amplitude of the modulation signal, and a signal combining unit that superimposes the modulation signal after the amplitude is controlled on the image signal. | 02-04-2010 |
20110063488 | SENSOR DRIVING CIRCUIT, DRIVER DEVICE, IMAGE READING APPARATUS, AND IMAGE FORMING APPARATUS - There is provided a sensor driving circuit that includes: an image sensor that converts light reflected from an original to be read into electric signals; a driver circuit that drives the image sensor; and a timing generator circuit that outputs timing signals for use in control of the image sensor. The driver circuit includes a first inverting buffer circuit and a second inverting buffer circuit that are equivalent to each other and arranged in series connection of two stages with the first inverting buffer circuit at the first stage of the two stages. The timing signal output from the timing generator circuit has the same polarity as the polarity of an input signal fed to the image sensor. | 03-17-2011 |
20120008173 | ANALOG SIGNAL BUFFER AND IMAGE READING DEVICE USING THE ANALOG SIGNAL BUFFER - The analog signal buffer is connected with a photoelectric converter to convert an optical image to an analog signal and an analog signal processing circuit to convert the analog signal to a digital signal, and transmits the analog signal to the analog signal processing circuit. The analog signal buffer includes a first buffer having a NPN transistor; and a second buffer having a PNP transistor. The first buffer includes a circuit to block a reverse current caused in the analog signal buffer by dropping of a voltage output from the photoelectric converter. | 01-12-2012 |
20120092732 | SIGNAL BUFFER CIRCUIT, SENSOR CONTROL BOARD, IMAGE SCANNER, AND IMAGE FORMING APPARATUS - A signal buffer circuit includes a buffer to conduct a buffering operation for transmitting a signal to a subsequent unit; a resistor connected between an input side and an output side of the buffer; and a variable impedance device connected in series to the output side of the buffer. The variable impedance device is at low impedance when the buffer is conducting the buffering operation and at high impedance when the buffer is not conducting the buffering operation. | 04-19-2012 |
20120224205 | SIGNAL PROCESSING CIRCUIT, IMAGE SCANNER, AND IMAGE FORMING APPARATUS - A signal processing circuit includes a generator, a transmission unit, a control unit, and a mode selector. The generator generates a process-required signal. The transmission unit transmits the process-required signal to a unit disposed after the transmission unit. The control unit supplies respective control signal to the generator and transmission unit. The control unit includes a reference clock generator constantly operated for generating a reference clock signal when the signal processing circuit is operated. The mode selector selects and shifts an operating mode of the signal processing circuit between a first mode and a second mode. In the first mode, the generator and transmission unit are supplied with respective normal control signal from the control unit for a normal operation. In the second mode, the generator is supplied with a control signal different from the normal control signal, and the transmission unit is supplied with the same normal control signal. | 09-06-2012 |
20130063792 | METHOD AND DEVICE FOR DRIVING LIGHT SOURCE, IMAGE READER, AND IMAGE FORMING APPARATUS - A light-source driving device includes a driving unit configured to drive a light source unit that emits light onto an object; and a driving control unit configured to control the driving unit to drive the light source unit in a first driving mode and a second driving mode. A light emission time of the light source unit is controlled in the first driving mode. An instantaneous value of a quantity of light of the light source unit being controlled in the second driving mode. | 03-14-2013 |
20140029065 | IMAGE SCANNING DEVICE AND IMAGE FORMING APPARATUS - According to an embodiment, an image scanning device includes: a light source unit that emits light onto an original to be scanned; a photoelectric conversion unit that converts light from the original to an electric signal; a converting unit that converts the electric signal from the photoelectric conversion unit into digital image data; and a black correcting unit that performs black correction by correcting pixel-by-pixel black levels of pixels contained in pre-scanning digital image data obtained before the original is scanned based on a ratio of a dark-current black level of a pixel contained in ongoing-scanning digital image data obtained during scanning of the original to a dark-current black level of the pixel contained in the pre-scanning digital image data, and subtracting the corrected pixel-by-pixel black levels from the ongoing-scanning digital image data. | 01-30-2014 |
20140204427 | PHOTOELECTRIC CONVERSION ELEMENT, IMAGE READING DEVICE, AND IMAGE FORMING APPARATUS - A photoelectric conversion element includes: a plurality of AD conversion units that convert respective analog signals representing amounts of charge stored in a plurality of light receiving elements into digital signals in parallel; and a parallel-serial conversion unit that performs parallel-serial conversion on the digital signals into which the analog signals have been converted in parallel by the AD conversion units. | 07-24-2014 |
20140204432 | IMAGE READING APPARATUS, IMAGE FORMING APPARATUS, AND IMAGE READING METHOD - An image reading apparatus includes: light-receiving elements arranged in a main-scanning direction to perform photoelectric conversion pixel by pixel; AD converter units that convert each piece of analog data photoelectric-converted by the light-receiving elements into parallel pieces of digital data; a storage unit that stores therein each of the digital data converted by the AD converter units; a converter unit that reads the digital data stored in the storage unit and converts the read digital data into serial data in the main-scanning direction; a readout control unit that changeably controls a readout start pixel and a readout end pixel of the serial data in the main-scanning direction; and a period change unit that changes a period in which the converter unit converts digital data into serial data in the main-scanning direction based on the readout start pixel and the readout end pixel. | 07-24-2014 |
20140211273 | SOLID-STATE IMAGE SENSING DEVICE, IMAGE READING APPARATUS, AND IMAGE FORMING APPARATUS - A solid-state image sensing device includes: a photoelectric conversion unit that converts light into electrical signals for respective pixels and outputs the electrical signals; a signal separation unit that separates an offset signal, which is generated due to dark current, from each of the electrical signals outputted by the photoelectric conversion unit and outputs image signals which are electrical signals converted from light for the respective pixels; and a signal adding unit that adds the image signals, which is outputted from the signal separation unit, for each group of a plurality of pixels. | 07-31-2014 |
20140368893 | PHOTOELECTRIC CONVERSION ELEMENT, IMAGE READING DEVICE, IMAGE FORMING APPARATUS, AND IMAGE READING METHOD - A photoelectric conversion element includes: a plurality of light receiving elements that are arranged in a main-scanning direction, are arranged in a sub-scanning direction according to colors of light to be received, and accumulates electric charge due to light exposure; and a plurality of AD conversion units that convert analog signals that indicate quantities of electric charge accumulated in the light receiving elements into digital signals are provide for each of groups each consisting of a predetermined number of pixels corresponding to the light receiving elements arranged in the sub-scanning direction. The AD conversion units convert the analog signals into the digital signals in an order in which the light receiving elements in the group are exposed to light. The light receiving elements constitute a correction unit that performs correction so as to reduce a difference relating to the timings in the sub-scanning direction. | 12-18-2014 |