Oki Electric Industry Co., Ltd.

Oki Data Corporation

Oki Electric Industrial Co., Ltd.

Shinichi Katakura

Jiro Tanuma

Katsuyuki Ito

Akira Nagumo

Kazuhiko Nagaoka

Nobuo Wakasugi

Hiroshi Kikuchi

Toshikazu Ito

Yoshiharu Momiyama

Norio Nakajima

Takehiko Okubo

Hiroshi Okada

Hisao Ono

Masato Sakai

Takao Uchida

Tadao Shimizu

Kuniharu Hayashi

Toru Ishihara

Koichi Matsuzaki

Noboru Otaki

Masato Nagata

Makoto Yabuki

Koji Ida

Hiroshi Sakaino

Koichi Negishi

Yoshitomo Koga

Toshikaru Ito

A non-impact printer has a print data correction circuit for providing a print data correction processing for video signals transmitted from a printing control unit to produce correction output data or patterns for printing on basic raster lines and other correction output data or patterns for printing on sub-raster lines. Those correction output data or patterns are supplied to the print head in the form of a real printing data signal.

Printer having print data correction circuit

Bit data of a received video signal is partially converted into a first signal representing a data sequence corresponding to the resolution of an LED head. The first signal is transmitted to the LED head in the form of a real printing data signal that is to be printed on a basic raster line in synchronism with a line timing signal. The remaining bit data of the received video signal, which are not converted into the first signal, are converted into a second signal representing another data sequence, and then stored in a line buffer. The second signal stored in the line buffer is transmitted to the LED head in the form of a real printing data signal that is to be printed on an additional raster line in synchronism with an additional line timing signal. The LED head drive energy with which the basic raster lines are printed and another LED head drive energy with which the additional raster lines are printed are set independently of each other. The LED head may be provided with such a resolution function.

Printer having circuit for providing improved printing quality

A non-impact printer include a print head with a plurality of print elements such as light emitting diodes (LEDs). A driver drives the plurality of LEDs in accordance with logical states of corresponding bits of print data. A non-volatile memory stores energy specifying data. The energy specifying data describes an amount of drive energy that should be supplied to each of the plurality of print elements when each of the plurality of LEDs are driven during the printing. A random number generator generates random numbers. An adder adds the random numbers to the values of the energy specifying data to produce the energy specifying data that fluctuates within a predetermined range. Each of the plurality of LEDs is supplied with an amount of drive energy to in accordance with the fluctuating energy specifying data, thereby rendering the variations in print density of an entire image not detectable.

Non-impact printer

A color image recording apparatus operates in a color print mode and in a monochrome printing mode. A set of color print heads are driven in accordance with corresponding color image data. A monochrome print head is driven in accordance with black image data. A controller transmits in parallel or in serial the color image data and the black image data to the corresponding print heads in a color printing mode. The controller transmits the black image data faster in the monochrome printing mode than in the color printing mode, thereby increasing printing speed. The controller may include signal processing circuits such as compressing circuits and expanding circuit for the respective color image data and black image data. In the monochrome printing mode, the controller divides the black image data into a plurality of segments and supplies the segments in parallel to the signal processing circuits. The signal processing circuits process the segments and supply the processed data to the monochrome print head in a predetermined sequence, thereby increasing printing speed.

Printer

A non-impact printer has a print data correction circuit for providing a print data correction processing for video signals transmitted from a printing control unit to produce correction output data or pattern for printing on the basic raster line and other correction output data or patterns for printing on the sub-raster lines. Those correction output data or patterns are supplied to the print head in the form of a real printing data signal.

An LED printer includes a printing control unit and an LED head. When a video signal received at the control unit has a higher resolution than the LED head, the control unit carries out the logical AND between successive bit data of the video signal to convert the video signal to a first signal. Corresponding to a line timing signal, this first signal is transferred as a head data signal to the LED head and is then printed on a basic raster scanning line. Further, the control unit also carries out the exclusive-OR between the successive bit data of the video signal so that the video signal is converted to a second signal and outputted to a line buffer. Corresponding to an additional line timing signal, the second signal is transferred as another head data signal to the LED head and is printed on an additional raster scanning line. The LED head drive energy for performing printing along the basic raster scanning line is set independently.

Printer and process for printing different size dots by setting drive

A print head for non-impact printer is, for example, an LED head which comprises a plurality of light-emitting elements, LED drivers for selectively causing a drive current to flow into the light-emitting elements on the basis of the print data, a non-volatile memory for storing the modification data related to the value of the drive current. The modification data are determined in advance at the manufacturing process on the basis of the measured result when the light-emitting elements were driven by the LED driver so that all the light-emitting elements emit substantially same amount of light at the printing operation.

Non-impact printer and a print head thereof

A toner image fixing device in an electrophotographic image forming apparatus has a heating roller containing a heater and a backup roller, a surface of which is in contact with a surface of the heating roller. A toner image on the paper is fixed by causing the paper to pass through a contacting portion of the heating roller and the backup roller. The toner image fixing device also has a driving device for supplying driving power to the heating roller or the backup roller to rotate both the heating roller and the backup roller, and a controller. The controller controls the driving section in such a way that both the heating roller and the backup roller begin to rotate intermittently immediately after an electric power supply switch of the apparatus is turned on and heat generation from the heater is initiated, and subsequently begin to rotate continuously when the backup roller achieves one revolution by the intermittent rotation. Alternatively, the rotation speed of the heating roller and backup roller is gradually and continuously increased immediately after electric power is initiated and subsequently reach a constant speed.

Toner image fixing device with rotational control of fixing rollers

Data are transmitted from a control device through an interface cable to a set of driver devices in synchronization with an external clock signal, or a complementary pair of external clock signals. The signal line or lines carrying the external clock signal or signals are terminated at both ends by resistors with resistance values matching the characteristic impedance of the interface cable. Each driver device has a comparator that compares the external clock signal with a regulated reference voltage, or compares the two complementary external clock signals with each other, and thereby generates an internal clock signal. The driver devices receive the data in synchronization with these internal clock signals.

High-speed signal transmission circuit with reduced electromagnetic

Bit data of a received video signal is partially converted into a first signal representing a data sequence corresponding to the resolution of an LED head. The remaining bit data of the received video signal, which are not converted into the first signal are converted into a second signal representing another data sequence corresponding to the resolution of an LED head. The LED head includes a resolution conversion circuit which converts the video data into the first signal and the second signal. The signals are stored in a shift register having a plurality of line buffers. The first signal is printed on a basic raster line and the second signal is printed on an additional raster line. An LED head drive energy with which basic raster lines are printed and another LED head drive energy with which additional raster lines are printed are set independently of each other.

A printer receives a bit-mapped image signal representing an arbitrary bit-mapped image, and generates an independent pattern signal having a certain dot density, representing a shade of gray. The printer discriminates between edge dots and interior dots in the bit-mapped image signal, and generates a corresponding discrimination signal. A logic circuit outputs edge dots that are present in the bit-mapped image signal, and interior dots that are present simultaneously in the bit-mapped image signal and pattern signal. The dots output by the logic circuit are printed to produce outlines filled with a shade of gray.

Printer for printing bit-mapped image responsive to bit-mapped image

Bit data of a received video signal is partially converted into a first signal representing a data sequence corresponding to the resolution of an LED head. The first signal is transmitted to the LED head in the form of a real printing data signal that is to be printed on a basic raster line in synchronism with a line timing signal. The remaining bit data of the received video signal, which are not converted into the first signal, are converted into a second signal representing another data sequence, and then stored in a line buffer. The second signal stored in the line buffer is transmitted to the LED head in the form of a real printing data signal that is to be printed on an additional raster line in synchronism with an additional line timing signal. The LED head drive energy with which the basic raster lines are printed and another LED head drive energy with which the additional raster lines are printed are set independently of each other.

Printer which prints with a resolution exceeding led head resolution

A method for printing an image including the step of generating a basic line timing signal and an additional line timing signal providing timings between respective timings of the basic line timing signal, producing a matrix by a video signal of a number of lines corresponding to a ratio of a resolution of the video signal to a resolution of a printing portion, producing one dot of a grayscale data signal having grayscale information of dots of the matrix, and driving a printing head by head drive energy determined according to the grayscale data signal, when an image is printed by using the printing head having a resolution in the raster direction less than the resolution of the video signal for forming the image to be printed. Although a number of dots for forming the image is reduced, amount of information is not reduced since dot information is converted into the grayscale information, so that high-quality printing is possible at a time of printing for grayscale.

Image printing method and non-impact printer wherein a received video

A printer includes a controller for providing a sequence control for the printer in its entirety in response to a control signal and a video signal from another controller. A printer head is adapted for latching and printing a printing data signal transmitted from the controller. Print data arithmetic and logic circuitry provides a logical operation processing for video data signals, counting video clock signals transmitted from the controller, and includes storage for storing the video data signals transmitted from the controller, a selector responsive to reference line timing signals for selectively alternately outputting the video data signals, an additional line signal generator for generating from video signals received from the controller, a video data signal representing an additional line destined for between reference lines during an interval of timing, and logical operation circuitry for performing a logical operation for the video data signals read out from the storage and supplying to the printer head the video data signals subjected to the logical operation in the form of the printing data signal.

Growing community of inventors

Tokyo, Japan

Shinichi Katakura