Minolta Camera Kabushiki Kaisha

Minolta Camera Kabushiki

Masaaki Nishiyama

Shigeo Ogino

Takashi Kadono

Atsuyuki Tanaka

Kazuyuki Fukui

Takanobu Yamada

Shozo Kaieda

There is disclosed an image forming apparatus for generating a printing signal having a pulse width according to image density data corresponding to an image to be formed and forming dot images on a paper, each dot image having a size corresponding to the pulse width. An integrating circuit integrates the image density data for a predetermined integration period and outputting integrated image density data, and a comparator compares the integrated image density data with a predetermined threshold data and generating a printing signal having a pulse width corresponding to the comparison result thereof.

Image forming apparatus comprising integrating means for integrating

An apparatus such as a digital printer for forming a image with use of electrophotographic process with a reversal development system, the density is controlled automatically by varying the sensitizing electric potential V.sub.O of the photoconductor and the bias electric voltage V.sub.B of the development unit according to the detected density of the standard toner pattern, while gradation correction fog elimination and/or color balance can be performed at the same time automatically or manually by adjusting V.sub.O and V.sub.B.

Apparatus for forming an image with use of electrophotographic process

An image forming apparatus such as a digital color copy machine is disclosed. The image forming apparatus provides an image reader, an amplifier for amplifying image signals read by the image reader, a laser driver for driving a laser diode to form an image on a recording medium and a switching circuit for switching the amplification gain according to the kind of image to be formed.

Image forming apparatus and method therefor

There is disclosed an image forming apparatus having a function for correcting the gradation characteristic of an image formed so as to be linear to the gradation degree. The image forming apparatus has a correction circuit for correcting inputted graduatin data to gradation data having a number of gradation degrees larger than that of the inputted gradation data to represent gradation data of a document image more precisely, for example in a range of low gradation. There is also disclosed a test mode for detecting an actual .gamma.-characteristic of the image forming apparatus by measuring toner densities of test images formed on a recording medium beforehand.

Image forming apparatus

There is disclosed an image forming apparatus comprising a semiconductor laser diode for emitting a laser light onto a photoconductor so as to form an electrostatic latent image thereon. The electrostatic latent image is developed using toner so as to form a visible toner image on the photoconductor, and there is set a predetermined bias voltage to be supplied to the laser diode. The set bias voltage is applied to the laser diode, and also a driving voltage is applied thereto responsive to image data. When no image data are inputted, the predetermined bias voltage is applied to the laser diode, and a density of a toner image formed on the photoconductor is detected. A controller sets a bias voltage to be applied to the laser diode responsive to the detected density of the toner image.

Image forming apparatus comprising means for setting a proper bias

A data processor for generating character images in a bit map memory according to character code data obtained from an external host computer. The data processor transforms the orthogonal positional data of the character code data into linear addresses for use in a linear address space where the linear address space has an origin corresponding to the origin of said orthogonal coordinate.

Data processor for generating character image

Clocking circuitry for a character generator wherein a control microprocessor controls character generated by hardwired logic through an interface microprocessor, the clocking circuitry including an oscillator which supplies an output to a divider which supplies a reduced frequency signal to the control microprocessor. The output of the oscillator is also supplied to the output of a timing controller. The timing controller further receives a print signal from the interface microprocessor and supplies a plurality of timing signals to the hard wired logic character generator.

Character generator with clocking circuitry

A character image generating circuit includes a text buffer for storing character code data corresponding to one page, a first memory for storing character image data corresponding to a section of one page, and a second memory for storing compressed character image data corresponding to one page. A depiction control unit coupled with a font memory is provided for converting the character code data, a section at a time from the text buffer, to character image data which is temporarily stored in the first memory. The depiction control unit also compresses the character image data obtained from the first memory to produce compressed character image data which is stored in the second memory. The second memory further receives compressed character image data of other sections. A reconstruction circuit is provided for reconstructing the compressed character image data of one page from the second memory back to the original character image data.

Character image generating circuit

A signal processing device comprises buffer memory means for outputting a coded signal in parallel by a signal of predetermined bits, shifting means for shifting the coded signal so that the head bit of the coded signal become the head of the outputted signal, decoding memory means for decoding the coded signal to a run length signal having information of the run length of the coded signal, and outputting a shifting signal designating a bit number of the coded signal corresponding to the number to be shifted, into said shifting means. Accordingly, said signal processing device enables to decode a coded signal at a higher speed than a conventional image signal processing device and to output an image signal into an electrophotographic printer or a CRT display, synchronizing with a processing speed of the electrophotographic printer or a sub scanning speed of the CRT display.

Image signal processing device

A character generator, comprising: a font memory for storing dot patterns of fonts; a first-in first-out memory for loading dot pattern data in unit of one byte successively, which generates a load request signal when the memory has empty spaces; an input control unit for accessing a dot pattern of a font to be printed and for transmitting a dot array data of one byte to the first-in first-out memory when the load request signal is received; and an output control unit for sending an output request signal to the first-in first-out memory to receive dot array data from the first-in first-out memory, and for transmitting the dot array data to a dot-image printer synchronously with a load request signal from the dot-image printer.

Dot image character generator employing a font memory

A character signal generator which is capable of processing a large amount of data at a high speed without increase of the load of software and also capable of effectively using the storing region of text buffer by employing the circuit structure that the character codes to be output are continuously written on the text buffer and the row end code is written at the end of each row, thereby when this code is detected, the counting operation of address counter is suspended.

Character signal generator

Disclosed herein is a character generating device of a raster scan system which comprises a region data storage means for storing display region data predetermined with respect to each of the character codes and a region counter which is set by the display region data. The region data storage means and the region counter are correlated with each other, whereby the dot output is counted by the region counter for generating a signal to output the next character when the count value reaches a set region datum value.

Growing community of inventors

Toyohashi, Japan

Masaaki Nishiyama