Abstract: A data processing device capable of digital processing of analog data and obtaining analog output signals from the result of digital processing, without the use of analog-digital converters or digital-analog converters.

Abstract: Adjustment of a gain and an offset of a data processing apparatus for controlling the operation of a copying machine or the like can be performed all at once without requiring adjustment of individual components making up the apparatus, such as an A/D converter. Changes in the gain and/or offset of the apparatus which occur with time can be compensated for. Data fetch and output can be efficiently performed.

Abstract: An analog-to-digital converter comprises an output generator for forming an output signal in response to application of a start signal; a comparator for comparing an analog signal, to be converted to a digital signal, with the level of the output signal formed by the output generator and for providing an output representing the time period from initiation of formation of the output signal to occurrence of a predetermined relation between the output signal and the analog signal; and a clock signal generator. The converter further comprises a digital computer that includes an output terminal from which the start signal is applied to the output generator and an input terminal for receiving the output from the comparator.

Abstract: An electrostatic recording apparatus including an image former for forming an electrostatic latent image, a device for developing the formed image, and a device for applying a bias voltage to the developer device in accordance with an identification as to whether the original relates to a character image or a half tone image. The bias voltage applying device includes first and second voltage generators for generating different bias voltages, and a selector device for selecting between the first and second generators. The bias voltage applying device is operable, during a developing time, to apply the selected bias voltage to the developer device, and during a non-developing time, to apply thereto a bias voltage different from the bias voltage applied during developing.

Abstract: An image forming device constracted with an image forming device, a memory device to store therein a plurality of programs for stable control of an image quality, and a device for selecting and executing one of the programs stored in the memory device. The image forming device is further provided with a humidity detection device, a temperature control device, and a control device to effect potential control.

Abstract: A power supply device has improved power efficiency and stability for use in a copier or the like. The primary power supply to the device being switched with a constant turned-off period to achieve variable power supply control.

Abstract: There is disclosed an electrophotographic image forming apparatus in which toner loss by deposition to non-image area is prevented by detecting the surface status of photosensitive member and applying thus detected state to the image developing device.

Abstract: There is disclosed an image forming apparatus capable of compensating for fluctuations in the image forming conditions thereby ensuring optimum image formation.The image forming apparatus is provided with a control for modifying outputs from a processor for image formation when the length of pause in the image formation operation of the processor exceeds a predetermined value.

Abstract: An image forming device constructed with an image forming device, a memory device to store therein a plurality of programs for stable control of an image quality, and a device for selecting and executing one of the programs stored in the memory device. The image forming device is further provided with a humidity detection device, a temperature control device, and a control device to effect potential control.

Abstract: An image formation apparatus has detection signal generator for generating an analog detection signal, reference signal generator for generating an analog reference signal of a reference level, A/D converter for converting the analog signal into a digital signal, and controller for causing the detection signal to be input to the A/D converter and putting out a desired control signal and for causing the reference signal to be input to the A/D converter and determining the then magnitude of the digital signal to thereby detect abnormality of the A/D converter.

Abstract: The invention provides an image formation apparatus having a photosensitive drum, primary and secondary chargers which are controlled by first and second high voltage transformers, respectively, a predischarge charger controlled by a predischarge high voltage transformer, a transfer charger controlled by a transfer high voltage transformer, an exposure lamp controlled by a light control circuit, a developing roller which receives a controlled bias voltage from an AC developing bias circuit, a surface potentiometer, and a microprocessor. In preliminary exposure, an original is exposed to light to form an electrostatic latent image on the photosensitive drum. The potential of this latent image is measured by the surface potentiometer so as to detect the potential of the original. Based on the potential of the original and hence a detected density of an image of the original, image formation conditions such as a development bias voltage, corona charge, and an original exposure voltage are corrected.

Abstract: An electrostatic recording apparatus has a sensor for detecting a surface potential of a photosensitive member on which an electrostatic latent image is formed and a controller for controlling a developing bias voltage in accordance with the detected surface potential. The developing bias voltage includes an A.C. component and a D.C. component which are selectively used in accordance with a latent image potential. The frequency of the A.C. developing bias and the magnitude of the D.C. developing bias are variable so that an optimum quality of image is reproduced.

Abstract: An image formation apparatus reproduces both an image of a text and a continuous tone image such as a photograph with excellent gradation. The AC bias voltage to be applied to a developing roller is controlled stepwise or continuously in accordance with the spatial frequency of an original.