Patents by Inventor Takao Kuwabara

Takao Kuwabara has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 6566676
    Abstract: In an image detector having alternately-aligned linear electrodes for a stripe electrode and linear sub-electrodes for a sub-electrode, short circuiting between the stripe electrode and the sub-electrode is prevented. An insulator layer having transparency to reading light is used outside a second electrode layer in which elements of the stripe electrode are aligned. Elements of the sub-electrode are placed alternately with the elements of the stripe electrode, outside the insulator layer. Thickness of the insulator layer is set as thin as possible to a degree not to cause short circuit between the elements of the two electrodes.
    Type: Grant
    Filed: September 21, 2000
    Date of Patent: May 20, 2003
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Takao Kuwabara
  • Publication number: 20030043064
    Abstract: In a signal detecting method of repeating the processes of initiating accumulation of charge signals by switching an integrating amplifier to an accumulator mode, retaining a first electric signal outputted from the integrating amplifier immediately after switching to the accumulator mode, finding a difference as a signal component between a second electric signal outputted from the integrating amplifier immediately before switching to a reset mode after completing accumulation of the charge signals and the first electric signal, and converting and outputting the signal component into a digital signal. Here, the signal component concerning a first charge signal is retained by second signal retaining means and then converted into the digital signal. Further, the integrating amplifier is switched to the accumulator mode after completing accumulation concerning the first charge signal but before completing conversion into the digital signal to initiate accumulation concerning a second charge signal.
    Type: Application
    Filed: August 29, 2002
    Publication date: March 6, 2003
    Applicant: FUJI PHOTO FILM CO., LTD
    Inventor: Takao Kuwabara
  • Patent number: 6515286
    Abstract: In a radiation detector: a CsI:Tl (or CsI:Na) scintillator receives a number X of radiation quantums for each pixel, and emits a number L of photons constituting fluorescent light in response to each radiation quantum; photoelectric converters containing Si (or Se) as a main component are arranged corresponding to respective pixels to receive the fluorescent light with an entrance efficiency T, and generate charges when the fluorescent light is detected; and a capacitor is connected to each photoelectric converter, and stores the charges generated by the photoelectric converter. When the radiation detector receives a 10 to 300 mR dose of the radiation, the numbers X and L, the entrance efficiency T, the fill factor F and the photoelectric conversion efficiency &eegr; of each photoelectric converter, and the maximum storable charge amount Q of the capacitor satisfy a relationship X·L·T·F·&eegr;≦Q.
    Type: Grant
    Filed: April 16, 2001
    Date of Patent: February 4, 2003
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Takao Kuwabara
  • Publication number: 20030010942
    Abstract: An image detector for use has a constitution of serial lamination of a first stripe electrode, a first rectifying layer with multiple photodiodes which takes on conductivity upon receiving irradiation of recording light, a second rectifying layer with multiple diodes of a reverse polarity to the first rectifying layer, and a second stripe electrode. Upon recording, a voltage is applied between the first stripe electrode and the second stripe electrode, whereby uniform electric charges are accumulated in the capacitor. Then, the recording light is irradiated from the first stripe electrode side, so that electric charges for a latent image on the capacitor are annihilated in accordance with a dosage of the recording light. Upon retrieval, a given voltage is applied between each of elements on the first stripe electrode and elements on the second stripe electrode, whereby a charged currents flowing into the image detector 10 is detected.
    Type: Application
    Filed: July 9, 2002
    Publication date: January 16, 2003
    Applicant: FUJI PHOTO FILM CO. LTD.
    Inventor: Takao Kuwabara
  • Patent number: 6501089
    Abstract: Disclosed herein is an image detector including a first stripe electrode, a photoconductive layer which exhibits photoconductivity when irradiated with recording light, a rectifying layer 14 having a large number of diodes, and a second stripe electrode, which are stacked in the recited order. The elements of the first stripe electrode and the elements of the second stripe electrode are disposed so that they cross approximately perpendicularly. Voltage is applied from a power source between both elements to store uniform electric charge in a charge storage portion. Then, recording light is irradiated through the side of the first stripe electrode so that the latent image charge stored in the charge storage portion disappears according to the dose of the recording light. During reading, a predetermined voltage is applied between each of the elements of the first stripe electrode and all the elements of the second stripe electrode.
    Type: Grant
    Filed: August 21, 2000
    Date of Patent: December 31, 2002
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Takao Kuwabara
  • Publication number: 20020146314
    Abstract: In a pump turbine which can be operated in a pumping mode or a generating mode by switching the rotating direction of a runner, the discharge passing through the runner is adjusted based on a wicket gate opening; the speed of the runner is sensed; a target speed is temporarily set to a first speed different from a rated speed on generation starting; a response speed of a speed control via discharge adjusting means is controlled to a lower level after the speed reaches the target speed than that before the speed reaches the target speed; and finally, the target speed is slowly led to the rated speed, thus enhancing the stability of the speed when the turbine is started and enlarging a head range in which synchronization is achieved.
    Type: Application
    Filed: March 15, 2002
    Publication date: October 10, 2002
    Inventor: Takao Kuwabara
  • Patent number: 6455832
    Abstract: Histogram preparation means 22 prepares a histogram of the image data D (p, i) of each detecting element which is read out in the dark (bright) state. With respect to the data value Dmax at which the maximum frequency in the histogram, Hmax, is provided, defect discrimination value determination means 23 determines the lower defect discrimination value Dc1 and the upper defect discrimination value Dc2 at which the frequency in the histogram first comes down to or below the specified frequency (0, for example), starting from the maximum frequency Hmax. Discrimination means 24 takes the ranges under the lower defect discrimination value Dc1 and over the upper defect discrimination value Dc2 as the defective ranges, and discriminates all the detecting elements outputting a detection signal in such a defective range as defective elements in the dark (bright) state.
    Type: Grant
    Filed: December 27, 1999
    Date of Patent: September 24, 2002
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Takao Kuwabara
  • Patent number: 6336322
    Abstract: An object of the present invention is to provide a pump turbine capable of improving the stability of the governor by fully lessening the influences by the S-characteristics even when the running point of the pump turbine is in the S-characteristics region.
    Type: Grant
    Filed: November 8, 2000
    Date of Patent: January 8, 2002
    Assignees: Hitachi, Ltd., The Kansai Electric Power Co., Inc.
    Inventors: Takao Kuwabara, Kei Katayama, Hiroto Nakagawa, Haruki Hagiwara
  • Publication number: 20010038076
    Abstract: In a radiation detector: a CsI:Tl (or CsI:Na) scintillator receives a number X of radiation quantums for each pixel, and emits a number L of photons constituting fluorescent light in response to each radiation quantum; photoelectric converters containing Si (or Se) as a main component are arranged corresponding to respective pixels to receive the fluorescent light with an entrance efficiency T, and generate charges when the fluorescent light is detected; and a capacitor is connected to each photoelectric converter, and stores the charges generated by the photoelectric converter. When the radiation detector receives a 10 to 300 mR dose of the radiation, the numbers X and L, the entrance efficiency T, the fill factor F and the photoelectric conversion efficiency &eegr; of each photoelectric converter, and the maximum storable charge amount Q of the capacitor satisfy a relationship X·L·T·F·&eegr;≦Q.
    Type: Application
    Filed: April 16, 2001
    Publication date: November 8, 2001
    Inventor: Takao Kuwabara
  • Patent number: 6250887
    Abstract: A reversible pump-turbine system having a discharge adjustment device such as guide vanes, which make it possible to safely stop a pump turbine at the time of emergency shutdown in a generating mode by performing a close operation using an inlet valve even if abnormality has occurred with the guide vanes, without causing abnormal water hammer. Also, at the time of pump mode emergency shutdown, reverse rotation can be prevented even if abnormality occurs in the guide vanes, and it is possible to achieve a safe stop while reducing the loads/stresses to the reversible pump-turbine.
    Type: Grant
    Filed: January 14, 1999
    Date of Patent: June 26, 2001
    Assignee: Hitachi, Ltd.
    Inventors: Takao Kuwabara, Masataka Harada
  • Patent number: 6210100
    Abstract: An upper reservoir-side conduit or a lower reservoir-side conduit is branched in the vicinity of pump-turbine ends and at least a first pump-turbine out of a plurality of pump-turbines which share the conduit portions located farther than the branch points with the other pump-turbine or pump-turbines is provided with a rotational speed increase detector. When it is detected that the rotational speed of the first pump-turbine has exceeded a second predetermined value higher than a rated speed, a command is issued also to at least one of the other pump-turbines to limit the guide vane closing speed in that pump-turbine to a speed approximately equal to or lower than the speed after the shift to a slow closing of the guide vanes.
    Type: Grant
    Filed: August 31, 1999
    Date of Patent: April 3, 2001
    Assignee: Hitachi, Ltd.
    Inventor: Takao Kuwabara
  • Patent number: 6208410
    Abstract: The present invention provides an image forming apparatus for forming an image on a recording material having light interference in which a latent image is formed when irradiated with light and the latent image is rendered visible when heated, which includes a latent image forming light source for irradiating the recording material with incoherent light to form a latent image. The image forming apparatus gives no interference band.
    Type: Grant
    Filed: August 27, 1998
    Date of Patent: March 27, 2001
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Takao Kuwabara
  • Patent number: 6091436
    Abstract: According to the improved method of correcting uneven densities in a thermal recording apparatus, on the basis of a preliminarily computed mathematical function that represents the relationship between the image data and the frictional force between the thermal recording material and the thermal head, a total sum of functional values corresponding to the image data of individual pixels in a present line, as well as a total sum of functional values corresponding to the image data of individual pixels in a preceding line are taken and the image data are corrected in accordance with the difference between the two total sums. This method can prevent effectively the occurrence of uneven densities due to the variation of recording density to provide for precise image recording.
    Type: Grant
    Filed: July 8, 1997
    Date of Patent: July 18, 2000
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Takao Kuwabara
  • Patent number: 6042331
    Abstract: An upper reservoir-side conduit or a lower reservoir-side conduit is branched in the vicinity of pump-turbine ends and at least a first pump-turbine out of a plurality of pump-turbines which share the conduit portions located farther than the branch points with the other pump-turbine or pump-turbines is provided with a rotational speed increase detector. When it is detected that the rotational speed of the first pump-turbine has exceeded a second predetermined value higher than a rated speed, a command is issued also to at least one of the other pump-turbines to limit the guide vane closing speed in that pump-turbine to a speed approximately equal to or lower than the speed after the shift to a slow closing of the guide vanes.
    Type: Grant
    Filed: February 27, 1998
    Date of Patent: March 28, 2000
    Assignee: Hitachi, Ltd.
    Inventor: Takao Kuwabara
  • Patent number: 6018355
    Abstract: The improved thermal recording apparatus for forming an image in accordance with image data on a thermal recording material using a thermal head comprises a correction data storage unit for holding shading correction data for the image data and at least one of weighting functions for performing weighting on a coefficient of shading correction of the image data, and an image processing unit that weights the shading correction data on the basis of at least one of the weighting functions, that calculates the coefficient of the shading correction and which then performs at least the shading correction on the image data. The correction data storage unit holds at least one of the respective weighting functions of shading correction coefficient associated with a recording density of the image data, a temperature of the thermal head, a recording speed of the image, temperature and humidity of the thermal recording material and a gradient of the thermal recording material.
    Type: Grant
    Filed: February 28, 1997
    Date of Patent: January 25, 2000
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Takao Kuwabara
  • Patent number: 5973713
    Abstract: The improved thermal recording apparatus using a thermal head comprises an image processing unit which receives image data from an image supply source and which performs sharpness compensation and other image processing jobs on the received image data to construct data for the image to be recorded thermally and thermistor for measuring a temperature of the thermal head, wherein the image processing unit changes the coefficient of sharpness compensation in accordance with the temperature of the thermal head. The thermal recording apparatus can sufficiently reduce the drop in image sharpness due to an increased temperature of the thermal head and, optionally, the drop in image sharpness due either to an increased recording speed or to a reduced gamma value of the thermal material or to both factors to ensure the consistent production of unblurred, high-quality images.
    Type: Grant
    Filed: February 10, 1997
    Date of Patent: October 26, 1999
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Takao Kuwabara
  • Patent number: 5886724
    Abstract: In the improved thermal recording method in which image data supplied from an image data supply source are subjected to specified image processing jobs and in which a thermal head is driven in accordance with the processed image data so as to perform thermal recording, image processing jobs are performed in a specified order such that sharpness correction and tone correction are followed by shading correction and correction of resistance values which, in turn are followed by compensation for temperature elevation, provided that calculation treatment of respective values of the image data for the compensation for temperature elevation is performed either prior to or after either one of the corrections that are performed subsequent to the tone correction. It is preferred that black ratio correction and/or load variation correction are also performed after the shading correction and the correction of resistance values, and prior to the compensation for temperature elevation.
    Type: Grant
    Filed: April 1, 1997
    Date of Patent: March 23, 1999
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takao Kuwabara, Tetsuya Kojima, Toshitaka Agano
  • Patent number: 5668589
    Abstract: A thermal recording device scans a laser beam over a thermosensitive recording medium which comprises a support coated with a coloring agent, a color developer, and a light absorbing dye and produces a color having a density commensurate with the lever of a thermal energy applied thereto, thereby to record an image thereon. The thermal recording device has a laser beam applying mechanism for emitting and applying a laser beam modulated by an image to be recorded to the thermosensitive recording medium, a temperature or humidity detecting mechanism for detecting a temperature or humidity with respect to the thermosensitive recording medium, and a controller for correcting the intensity of the laser beam emitted by the laser beam applying mechanism based on the humidity detected by the humidity detecting mechanism.
    Type: Grant
    Filed: March 31, 1994
    Date of Patent: September 16, 1997
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Takao Kuwabara, Yoshihisa Usami, Toshitaka Agano
  • Patent number: 5561358
    Abstract: A variable speed pumping up generator includes a first speed control unit for outputting a rotating speed command signal for controlling a pump turbine in accordance with a power output command and outputting an excitation control signal to an AC excitation unit of the generator, and a second speed control unit for controlling, in a generation mode, an amount of AC excitation from an AC excitation unit when a rotating speed of a rotary shaft departs from a lower limit setting or an upper limit setting. The setting is set in accordance with the rotating speed generated during a normal operation.
    Type: Grant
    Filed: December 20, 1994
    Date of Patent: October 1, 1996
    Assignees: Hitachi, Ltd., The Kansai Electric Power Co., Inc.
    Inventors: Takao Kuwabara, Masataka Harada, Yasuteru Oono, Hiroto Nakagawa
  • Patent number: 5456115
    Abstract: A method of detecting a counterflow in a pump comprises providing with detecting means for detecting variations in the discharge pressure of the pump and signal analyzing means for analyzing oscillation components contained in an output signal from the pressure detecting means, and detecting the pump's operating point to have entered a counterflow characteristic operation region when a waveform of the detection signal generated in association with the variations in the discharge pressure of the pump exhibits a predetermined spectrum distribution. Further, when it is detected that the operating point enters a counterflow characteristic operation region, the escape from that region is performed by temporally throttling the guide vane and temporally increasing the rotating speed.
    Type: Grant
    Filed: August 4, 1993
    Date of Patent: October 10, 1995
    Assignees: Hitachi, Ltd., The Kansai Electric Power Co., Inc.
    Inventors: Takao Kuwabara, Ezo Kita, Isao Yokoyama, Hiroto Nakagawa, Yasuteru Oono