Patents Examined by Mark J. Reinhart
  • Patent number: 5737007
    Abstract: In a laser scanner device in which a laser beam emitted from a laser diode is reflected in a main scan direction over a predetermined angle by a polygon mirror which rotates at a high speed, the laser beam is reflected from a flat mirror and received by a horizontal synchronizing detection sensor before the laser beam enters a scanning region in which a main scanning operation of the laser beam is performed to form an electrostatic image on a photosensitive drum. In response to the detection of the laser beam, the detection sensor produces a horizontal synchronizing signal which is used as a reference phase to determine a start phase of the main scanning operation.
    Type: Grant
    Filed: May 2, 1995
    Date of Patent: April 7, 1998
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Hiroyuki Kashima, Tsuyoshi Ohashi
  • Patent number: 5736999
    Abstract: A laser processing method irradiates an excimer laser beam at a surface of an object composed of a polymer material that absorbs the excimer laser beam. The polymeric object is substantially free of lubricants that reflect wavelengths within the range of operation of the excimer laser beam. The invention also relates to a nozzle plate of an ink jet device, which does not contain such lubricants, produced with an excimer laser beam.
    Type: Grant
    Filed: July 25, 1995
    Date of Patent: April 7, 1998
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventor: Hikoharu Aoki
  • Patent number: 5734392
    Abstract: The heater chip (1) of an ink jet printer (10) has two substrate-heater resistors (3a and 3b) powered by the same power supply (24) as are the nozzle heaters (5) on the chip. Printhead (12) carries chip (1) and moves across paper (16) alternately left-to-right followed by right-to-left. Operation is during the margin periods when the nozzle heaters are not in operation. The power supply is thereby efficiently utilized.
    Type: Grant
    Filed: September 14, 1995
    Date of Patent: March 31, 1998
    Assignee: Lexmark International, Inc.
    Inventor: Robert Wilson Cornell
  • Patent number: 5734412
    Abstract: A scan type laser marking device which scans the surface of an object conveyed in a predetermined area and applies a laser beam to the surface of the object to form a mark on the surface of the object, comprising an area storing section for storing the area; a start point coordinate storing section for storing coordinates of an irradiation start point in the area, the irradiation start point being located upstream relating to the direction of conveyance of the object; an end point coordinate storing section for storing coordinates of an irradiation end point in the area, the irradiation being located downstream relating to the direction of conveyance of the object; a mark reference point section for storing the coordinates of a reference point on the mark; and speed setting means for setting scanning speeds so that a marking operation is started when the mark reference point reaches the irradiation start point, and is ended when the mark reference point reaches the irradiation end point.
    Type: Grant
    Filed: December 5, 1994
    Date of Patent: March 31, 1998
    Assignee: Keyence Corporation
    Inventors: Hiroyasu Hasebe, Makoto Sakai, Katsuhiko Yasui
  • Patent number: 5729276
    Abstract: Higher quality printing is difficult in implementation in spatial light modulator printers. The two major problems are accomplishing gray scale within the line time constraints, and eliminating staircasing artifacts within the images printed (81). It can be improved by using an alternate way of resetting cells on the spatial light modulator when data is being loaded onto the cells, timing delay (86), horizontal offset (84), and differently sized pixels (80, 82).
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: March 17, 1998
    Assignee: Texas Instruments Incorporated
    Inventor: William E. Nelson
  • Patent number: 5729277
    Abstract: A system and method of correcting aberrations in an output image of an image transfer apparatus, the aberrations being due to variations in a velocity of a scanning surface in the image transfer apparatus. Specifically, laser printer banding effects are reduced by modifying the gray scale dithering concentration based on a sensed variation of drum rotation velocity. A closed loop feedback system monitors errors in the drum motion and compensates the modulation of the laser to help cancel out the perceivable amount of banding effect in the printed image.
    Type: Grant
    Filed: July 19, 1995
    Date of Patent: March 17, 1998
    Assignee: Hewlett-Packard Company
    Inventor: Robert D. Morrison
  • Patent number: 5726700
    Abstract: A thermal recording device records information on a heat-sensitive recording material which develops color in a density according to heat energy supplied thereto. The thermal recording device pre-heats the heat-sensitive recording material with heat energy less than energy necessary to develop color in the heat-sensitive recording material and scans the recording material with a laser beam modulated according to the information to be recorded. A region from the upper surface of the heat-sensitive recording material to a space above the upper surface of the heat-sensitive recording material through which the laser beam impinges upon the heat-sensitive recording material is isolated from the surrounding space at least at its sides and top by side isolating members and a top isolating member, and at least the top isolating member is transparent so that the laser beam impinges upon the heat-sensitive recording material through the top isolating member.
    Type: Grant
    Filed: April 1, 1996
    Date of Patent: March 10, 1998
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Shinji Imai
  • Patent number: 5724088
    Abstract: A control system for the laser diode of a raster output scanner, such as used in a laser printer, uses reflex exposure control and a high-speed drive circuit. With the creation of each pixel on the photoreceptor, a sensor receiving some of the light flux from the diode accumulates charge on a capacitor, and when the charge on the capacitor exceeds a predetermined amount, a reflex circuit acts to shut the laser diode off. The laser diode is modulated via a high-speed trigger circuit wherein the diode is maintained just below its lasing voltage.
    Type: Grant
    Filed: March 27, 1996
    Date of Patent: March 3, 1998
    Assignee: Xerox Corporation
    Inventor: Frank C. Genovese
  • Patent number: 5724087
    Abstract: An exposure method which has a step of offsetting a first scanning line bend by scanning means with a second scanning line bend by an image forming lens, and/or a step of correcting angles of optical axis of a plurality of light beams in accordance with the amount of a deviation in a subscanning direction due to a difference of the angles of incidence, so that a distance between scanning lines on a photosensitive body due to the plurality of light beams is corrected.An image forming apparatus which has an image forming lens for producing a second scanning line bend is so as to offset a first scanning line bend by scanning means, and/or correcting means for correcting angles of optical axis of a plurality of light beams in accordance with the amount of a deviation in a subscanning direction due to a difference of the angles of incidence, so that a distance between scanning lines on a photosensitive body due to the plurality of light beams is corrected.
    Type: Grant
    Filed: June 27, 1995
    Date of Patent: March 3, 1998
    Assignee: Fujitsu Limited
    Inventors: Takao Sugano, Masayuki Iwasa, Kazuki Ogawa
  • Patent number: 5724089
    Abstract: 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.
    Type: Grant
    Filed: February 21, 1995
    Date of Patent: March 3, 1998
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Akira Nagumo, Norio Nakajima, Shinichi Katakura
  • Patent number: 5724152
    Abstract: To properly cut light except for visible light and improve read precision, there is provided an image reading apparatus having a plurality of photoelectric conversion elements. The image reading apparatus includes an image information detecting unit in which the photoelectric conversion elements are arranged on a single chip, a first light-shielding unit, arranged near the photoelectric conversion elements, for transmitting specific visible light, and a second light-shielding unit, arranged near the photoelectric conversion elements at a position different from that of the first light-shielding unit, for partially shielding light except for the visible light.
    Type: Grant
    Filed: December 28, 1993
    Date of Patent: March 3, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshio Hayashi, Hiroshi Tanioka, Shinobu Arimoto, Kazuo Yoshinaga, Takehiko Nakai, Tsutomu Utagawa, Tetsuya Nagase, Nobuatsu Sasanuma
  • Patent number: 5724090
    Abstract: An image forming method and apparatus which forms an image by using PWM to properly reproduce tones at a low density in the image formation, and attain a high-quality image without reducing the resolution in the dot formation corresponding to a high density value. A color laser beam printer using the PWM to which the present invention is applied forms a latent image onto a photosensitive drum by the laser beam irradiated from a semiconductor laser. The waveform of a chopped wave signal used in the PWM is set to be unique with respect to each color component, and be asymmetrical to the center of each pixel represented by the image signal in synchronization with the waveform of the chopped signal. Accordingly, the interval of dots formed to correspond to each color component is relatively wide when the density value is small, while the interval is relatively narrow when the density value is large.
    Type: Grant
    Filed: November 22, 1996
    Date of Patent: March 3, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Mamoru Tanaka, Nobuyuki Ito
  • Patent number: 5721578
    Abstract: A gradation control method in a color thermal transfer printer is adapted to express one pixel by a dot matrix with two rows and two coles, control a density value of one dot with a time for energizing a heating element of a thermal head, and carry out mask patterning for plotting only one of four dots when the gradation of each color for one pixel is not more than a prescribed value while plotting only two of the four dots when the gradation is in excess of the prescribed value. At this time, employed is a mask pattern of necessarily plotting cyan and magenta on dots which are different from each other. A picture quality improving method in a staggered printing system is adapted to plot a noted dot when at least one of such conditions that density data of the noted dot is in excess of a prescribed density value and that density data of any of four dots most approximate to the noted dot is not more than a prescribed low density value is satisfied, even if the noted dot corresponds to that to be masked.
    Type: Grant
    Filed: December 27, 1994
    Date of Patent: February 24, 1998
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yoshiyuki Nakai, Yasushi Adachi, Tatsuya Tanaka, Toshio Takehara, Tsuyoshi Takeno
  • Patent number: 5721580
    Abstract: Disclosed is a laser diode driving apparatus in a optical information recording and reproducing apparatus by which the bottom power of a laser beam for the information recording and reproducing may be maintained stably at a target value. A bottom power corrected value is obtained by multiplying the peak power of a laser beam for the information recording by a predetermined coefficient. Then, the bottom power corrected value is added with a target bottom power to set the summed value as a corrected target bottom power. The bottom level of an optical power detection signal is subtracted from the corrected target bottom power to provide the remaining value as an error signal. The bottom power of the laser beam is adjusted on the basis of the error signal.
    Type: Grant
    Filed: December 27, 1995
    Date of Patent: February 24, 1998
    Assignee: Pioneer Electronic Corporation
    Inventors: Kiyoshi Tateishi, Junichi Furukawa
  • Patent number: 5721579
    Abstract: In an image forming apparatus in which scanning of a laser beam modulated by an image signal is performed, and a laser is forced to be turned on in a non-image period in line scanning of the laser beam, an interrupt request is issued to a microcomputer in response to a forced turn-on signal. In a routine that is called in response to the interrupt request, the level of the forced turn-on signal is checked. If no forced turn-on signal is generated, then acquisition of a detected laser beam intensity signal is inhibited. This ensures that the acquisition of the laser beam intensity signal is performed only when the laser is in a normal turn-on state. If a forced turn-on signal is generated, the laser beam intensity signal is acquired, and the laser beam intensity is adjusted according to the acquired value of the laser beam intensity signal.
    Type: Grant
    Filed: December 19, 1994
    Date of Patent: February 24, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yoshimi Ogasawara, Eihiro Sakaki
  • Patent number: 5719617
    Abstract: An illumination device for illuminating a surface to be illuminated, includes a light source and an irradiation optical system for mixedly projecting light beams from the light source to the surface, wherein the irradiation optical system has a first focal point with respect to a first plane, which is disposed at a position out of the surface.
    Type: Grant
    Filed: February 16, 1995
    Date of Patent: February 17, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuhiro Takahashi, Takahisa Shiozawa
  • Patent number: 5717450
    Abstract: A fibre laser (2) is used in data-recordal, such as dye diffusion thermal transfer printing. The fibre laser output (3) is modulated and scanned across a recording medium (4) of adjacent dye donor and receiver ribbons by a modulator (20) and galvanometer (16), so that an image is produced line-by-line in the medium (4) as it passes between spools (19). The fibre laser (2) may comprise a single-mode, neodymium-doped lasing core (5), a multimode pump core (6), an outer cladding (7), and a dichroic mirror (8) at each end, and may be pumped by beams (10) from laser diodes (9) coupled to the pump core (6) by optical fibres (11) and a lens (14). Instead of using a galvanometer (16), the output end of the fibre laser (2) may be moved itself across the recording medium (4), and/or a plurality of the fibre lasers (2) may be bundled together in a one or two dimensional array.
    Type: Grant
    Filed: April 21, 1995
    Date of Patent: February 10, 1998
    Assignee: Imperial Chemical Industries PLC
    Inventors: Kenneth West Hutt, Laurence John Robinson
  • Patent number: 5717451
    Abstract: A multihead type image recording apparatus is provided. This recording apparatus includes a single position detector and a position correcting circuit. The position detector detects positional components of an array of laser diodes of each of recording heads in an X-direction parallel to a traveling direction of the recording heads on a recording medium and a Y-direction perpendicular to the X-direction to determine an inclination of the laser diode array. The position correcting circuit adjusts the inclination of the laser diode array of each of the recording heads to a given common angle to compensate for a positional error in the X-direction of the laser diode array, and also controls timing of activation of the laser diodes to compensate for a positional error in the Y-direction of the laser diode array.
    Type: Grant
    Filed: September 8, 1995
    Date of Patent: February 10, 1998
    Assignee: Matsushita Graphic Communication Systems, Inc.
    Inventors: Tatsuya Katano, Shigeru Iemura
  • Patent number: 5706046
    Abstract: An image forming apparatus including a bit map data generating section for generating binary dot data for each color from image data, an image memory for storing the dot data, an edge dot discriminating section for discriminating edge dots positioned in an edge section, such as a curved-line section, a slanted-line section of characters, graphics, photo images, etc. in dot data for black stored in the image memory, and a dot modulating circuit for modulating the dot data so that the edge dots and printing dots other than black ones become smaller than black printing dots other than the edge dots. With this arrangement, since linear tone can be obtained even in a section with a deep color, excellent tone can be obtained in multi-color printing such as full-color printing. Therefore, reproducibility of tone of binarized image data can be improved, and jaggedness in an edge section can be improved so as to have a smooth line.
    Type: Grant
    Filed: March 21, 1995
    Date of Patent: January 6, 1998
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Koji Eki, Akihiro Nishi
  • Patent number: 5703631
    Abstract: Method of forming an orifice array for an ink jet printhead. Excimer laser radiation is used to ablate an orifice array in a cover plate having a removable backing, a front side layer formed from either an ablatable inactive material such as polyimide, a non-wettable material doped to absorb excimer radiation, or an ablatable inactive material such as polyimide with a very thin surface layer of a non-wettable material, and an intermediate layer formed from an adhesive material. First, a series of generally square indentations approximately 80 .mu.m on each side and which extends through the removable backing and the intermediate layer and partially through the front side layer to exposing an interior surface of the front side are formed at spaced locations along the back side surface of the cover plate. Next, a corresponding series of generally circular apertures approximately 40 .mu.
    Type: Grant
    Filed: May 5, 1992
    Date of Patent: December 30, 1997
    Assignee: Compaq Computer Corporation
    Inventors: Donald J. Hayes, W. Royall Cox