Patents by Inventor Tokuichi Tsunekawa

Tokuichi Tsunekawa 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: 4455071
    Abstract: A light measuring instrument for a single lens reflex camera, whose light measurement distribution can be changed easily, includes two light sensing elements with different light measuring ranges, whereby the desired light measuring distribution can be obtained by changing the outputs of the two light sensing elements.
    Type: Grant
    Filed: January 15, 1982
    Date of Patent: June 19, 1984
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masatake Kato, Tokuichi Tsunekawa
  • Patent number: 4429967
    Abstract: In the distance measuring system disclosed, light reflected from an object is converted into an electrical signal and processed to detect the distance to the object. Before the distance detecting operation, a signal level detecting operation is carried out in the distance measuring range and the gain of the signal processing or the amount of light for illuminating the object is automatically set for the distance detecting operation.
    Type: Grant
    Filed: June 23, 1982
    Date of Patent: February 7, 1984
    Assignee: Canon Kabushiki Kaisha
    Inventors: Ryuji Tokuda, Masahiko Ogawa, Tokuichi Tsunekawa, Shuichi Tamura
  • Patent number: 4425031
    Abstract: The active automatic focusing apparatus disclosed scans the object to be photographed with light from a light projector and includes a sensor sensing reflected light, a peak detector for detecting the peak value of the signal sensed by the sensor, a control producing a stop signal suitable for stopping focusing movement of the objective lens in accordance with the output of the peak detector, and a stop device for stopping the movement of the objective lens on the basis of the output of the control. A comparator compares the level of the detected signal with that of a preset noise signal so as to produce a first control signal when the level of the detected signal is higher than that of the noise signal. A given distance detector produces a second control signal when the objective lens is moved to a predetermined position corresponding to a distance at which a peak of the detected signal can be detected by the peak detector.
    Type: Grant
    Filed: May 21, 1981
    Date of Patent: January 10, 1984
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shuichi Tamura, Masahiko Ogawa, Tokuichi Tsunekawa, Ryuji Tokuda
  • Patent number: 4422741
    Abstract: A distance detecting device in which, with respect to an object whose distance is to be detected, the images of a first and a second field following different lines of sight and containing the object and different in range are scanned while, at the same time, continuous M quantized image element data regarding the first field image and continuous N (N>M) quantized image element data regarding the second field image are obtained and the M image element data regarding the first field image are stored in a first circulation type shift register while the first M image element data of the N image element data regarding the second field image are stored in a second circulation type shift register and the remaining N-M image element data are stored in a third shift register, and the comparison between the stored data of the first and second shift registers during one circulation of said stored data and the relative shift of n bits each of the stored data of the second and third shift registers with respect to the
    Type: Grant
    Filed: January 29, 1982
    Date of Patent: December 27, 1983
    Assignee: Canon Kabushiki Kaisha
    Inventors: Makoto Masunaga, Takao Kinoshita, Toshio Sakane, Tokuichi Tsunekawa, Kazuya Hosoe, Takashi Amikura, Isao Harigaya
  • Patent number: 4410261
    Abstract: This invention presents a range finding device when 1st and 2nd detection images of an object are scanned by signal storing type image sensing means to obtain image scan signals, which are quantized by quantization means to produce quantized image data for said 1st and 2nd detection images. On the basis of the thus obtained quantized image data, the location within the 2nd detection images of one set of M successive elements of the 2nd detection image which is most similar to M successive elements of the 1st detection image is detected, and with the aid of the data of this location, the distance between the device and the object is determined. According to this improved device, sequence control means, which controls a series of operations for range finding, will firstly cancel the signals stored in said image sensing means as unnecessary signals, when said series of operations is initiated, and then enables proper storing of image signals in the image sensing means so as to properly control the device.
    Type: Grant
    Filed: March 2, 1981
    Date of Patent: October 18, 1983
    Assignee: Canon Kabushiki Kaisha
    Inventors: Makoto Masunaga, Kazuya Hosoe, Tokuichi Tsunekawa, Yukichi Niwa, Mitsutoshi Ohwada, Noriyuki Asano
  • Patent number: 4391500
    Abstract: A single lens reflex camera having at least first and second light measuring circuits of different light measuring distribution for producing outputs representative of logarithmically compressed information which is a function of the brightness of a scene to be photographed, and a computer for computing the outputs of the first and second measuring circuits. A measuring sensitivity pattern selector is provided outside the camera housing. Upon adjustment of the mixture ratio of the light values, the computer is caused to produce a first output, and the outputs of the first and second light measuring circuits are computed by the aforesaid computer based on a predetermined relationship to produce a second output. When the difference between the first and second computer output falls within a certain range of values, exposure is controlled by the first computer output, and when the output falls out of the certain range of values by the second computer output.
    Type: Grant
    Filed: November 20, 1981
    Date of Patent: July 5, 1983
    Assignee: Canon Kabushiki Kaisha
    Inventor: Tokuichi Tsunekawa
  • Patent number: 4368978
    Abstract: This specification discloses an image scanning system in which an object image formed by an optical system is electrically scanned by utilization of a photosensor array device and the image scanning output then obtained is quantized to thereby provide quantized image data. According to the improvement of the present invention, there are obtained two different quantized image data, namely, first quatized image data quantized by a voltage level determined on the basis of the image scanning output from the sensor device and second quantized image data quantized by a predetermined fixed voltage level.
    Type: Grant
    Filed: July 8, 1980
    Date of Patent: January 18, 1983
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tokuichi Tsunekawa, Makoto Masunaga, Kazuya Hosoe, Yukichi Niwa, Mitsutoshi Owada, Noriyuki Asano
  • Patent number: 4366501
    Abstract: An image recording system in which an object image is caused to be formed on a solid state image transducer such as CCD each time a release is actuated, and the image signal stored on said image transducer is recorded as a video signal, thus a single frame image is recorded for each release. By controlling the storing operation of the image signal and the like, the exposure level for the image signal is adjusted to make it possible always to record and reproduce the image with regard to an optimum exposure state.
    Type: Grant
    Filed: April 18, 1979
    Date of Patent: December 28, 1982
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tokuichi Tsunekawa, Nobuaki Date, Hiroshi Aizawa, Kazuya Hosoe, Kazunori Urushibara
  • Patent number: 4346970
    Abstract: Disclosed is a TTL (Through-The-Lens) type focus detecting device for use in an interchangeable lens-equipped camera, in which a plurality of lenslets are positioned at or near the prescribed focal plane of the objective lens, each of the lenslets is associated with two or more pairs of photosensitive elements. Upon attachment of an objective lens to the camera body, one of the pairs of photosensitive elements for each lenslet is automatically selected to operate on the basis of the dimensions of the used objective lens. The outputs of the selected pairs of photosensitive elements for all the lenslets are processed to detect whether or not a positional difference between two images of an object formed with light beams from the objective lens at respective virtual exit pupils lying in almost symmetry with respect to the optical axis thereof is present, whereby the detection of whether or not the objective lens is in-focus is indicated.
    Type: Grant
    Filed: August 19, 1980
    Date of Patent: August 31, 1982
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takashi Kawabata, Tokuichi Tsunekawa, Kazuya Hosoe, Takao Kinoshita, Shinji Sakai, Tatsuya Taguchi
  • Patent number: 4335942
    Abstract: A camera provided with automatic focus detector is disclosed. The automatic focus detector drives a photographing lens toward the in-focus position by lens driving means in accordance with focus detection signal repeatedly put out from focus detecting means. The present invention is directed to improvement in focusing operation of such camera. Said lens driving means is allowed to drive the photographing lens toward the in-focus position only when the focus detection information signal continues to be constant longer than a predetermined time length. At the same time, the driving state of the photographing lens by said lens driving means is detected and display means is controlled by the detection signal to display the state of focusing now present.
    Type: Grant
    Filed: October 21, 1980
    Date of Patent: June 22, 1982
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tokuichi Tsunekawa, Takashi Amikura
  • Patent number: 4335405
    Abstract: In the disclosed MOS-image sensor, a plurality of signal-integrating type photo-sensitive elements are set to values that depend upon the light to which they have been exposed and the time of exposure. Readout gate switches responding to a readout address arrangement sequentially read out the content of the elements. Individual reset gate switches that respond to a reset address arrangement reset each of the elements a desired time prior to the readout so as to control the signal integration time of each of the elements.
    Type: Grant
    Filed: April 22, 1980
    Date of Patent: June 15, 1982
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshio Sakane, Tokuichi Tsunekawa
  • Patent number: 4333716
    Abstract: Disclosed is a focus detecting system in which first and second signals corresponding to image forming states at first and second positions each almost at the same distance before and behind a predetermined focal plane of an image forming optical system are obtained. A third signal corresponding to an image forming state at a third position different from the first and the second positions is also obtained. The in-focus state of the image formed by the image forming optical system is detected on the basis of a first comparison signal obtained by comparing the first and the second signals with each other, a second comparison signal obtained by comparing the first and the third signals with each other and a third comparison signal obtained by comparing the second and the third signals with each other.
    Type: Grant
    Filed: November 29, 1979
    Date of Patent: June 8, 1982
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshio Sakane, Kazuya Hosoe, Tokuichi Tsunekawa, Takao Kinoshita, Takashi Kawabata
  • Patent number: 4334220
    Abstract: A display device comprising a first semiconductor stripe and a second stripe of composite structure in which a great number of successive areas alternate between a semiconductor material having different type with respect to that of the first stripe and an insulating material or materials and which is positioned in side-by-side contact relation to the first stripe to establish P-N junctions. A resistor stripe connected lengthwise to the second stripe so that a voltage proportional to a value of information which is desired to be displayed is applied across a third stripe when first stripe is negatively biased, a corresponding number of successive semiconductor areas in the second stripe are caused to emit visible light, giving a viewer the impression of a continuous luminous stripe having a length representative of the information value.
    Type: Grant
    Filed: April 24, 1980
    Date of Patent: June 8, 1982
    Assignee: Canon Kabushiki Kaisha
    Inventors: Ryoichi Suzuki, Takashi Uchiyama, Kazuya Hosoe, Tokuichi Tsunekawa
  • Patent number: 4329033
    Abstract: A distance detecting device in which, with respect to an object whose distance is to be detected, the images of a first and a second field following different lines of sight and containing the object and different in range are scanned while, at the same time, continuous M quantized image element data regarding the first field image and continuous N (N>M) quantized image element data regarding the second field image are obtained and the M image element data regarding the first field image are stored in a first circulation type shift register while the first M image element data of the N image element data regarding the second field image are stored in a second circulation type shift register and the remaining N-M image element data are stored in a third shift register, and the comparison between the stored data of the first and second shift registers during one circulation of said stored data and the relative shift of n bits each of the stored data of the second and third shift registers with respect to the
    Type: Grant
    Filed: February 15, 1980
    Date of Patent: May 11, 1982
    Assignee: Canon Kabushiki Kaisha
    Inventors: Makoto Masunaga, Takao Kinoshita, Toshio Sakane, Tokuichi Tsunekawa, Kazuya Hosoe, Takashi Amikura, Isao Harigaya
  • Patent number: 4320948
    Abstract: The present invention relates to a motion detecting device for detecting the relative motion rate or velocity between an object and an optical instrument in an exposure control system by which the exposure time, i.e. the shutter speed of the instrument is controlled in response to the relative motion rate or velocity. The motion detecting device is designed to detect the displacement ratio or speed of the position of the center of gravity of the light distribution of the object image on the imaging plane, whereby the danger for misdetection due to the periodical fluctuation of the object brightness can be profitably avoided, being possible to detect only the relative movement between the object and the instrument.
    Type: Grant
    Filed: July 22, 1980
    Date of Patent: March 23, 1982
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuya Hosoe, Tokuichi Tsunekawa, Makoto Masunaga, Toshio Sakane
  • Patent number: 4306807
    Abstract: In the disclosed system, a light measuring circuit having a logarithmical amplifier, is constructed to produce pulses at a frequency corresponding to the output of the light measuring circuit. Pulses are counted during a time interval corresponding to the temperature characteristic of the light measuring circuit so as to obtain a count value corresponding to the light input free of the influence of temperature.
    Type: Grant
    Filed: June 4, 1979
    Date of Patent: December 22, 1981
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshio Sakane, Tokuichi Tsunekawa
  • Patent number: 4305657
    Abstract: This invention presents a range finding device when 1st and 2nd detection images of an object are scanned by signal storing type image sensing means to obtain image scan signals, which are quantized by quantization means to produce quantized image data for said 1st and 2nd detection images. On the basis of the thus obtained quantized image data, the location within the 2nd detection images of one set of M successive elements of the 2nd detection image which is most similar to M successive elements of the 1st detection image is detected, and with the aid of the data of this location, the distance between the device and the object is determined. According to this improved device, sequence control means, which controls a series of operations for range finding, will firstly cancel the signals stored in said image sensing means as unnecessary signals, when said series of operations is initiated, and then enables proper storing of image signals in the image sensing means so as to properly control the device.
    Type: Grant
    Filed: September 22, 1978
    Date of Patent: December 15, 1981
    Assignee: Canon Kabushiki Kaisha
    Inventors: Makoto Masunaga, Kazuya Hosoe, Tokuichi Tsunekawa, Yukichi Niwa, Mitsutoshi Ohwada, Noriyuki Asano
  • Patent number: 4301478
    Abstract: In the disclosed TV camera, a focus detecting device detects the focus of the image optical system by evaluating the image of the object whose image is to be picked up, on the basis of the picture image signal obtained at a predetermined position in the image pick up surface of the image pick up device. At least a part of the image to be evaluated is formed at a position within the scanning area of the image pick up device but outside of the effective image pick up area for TV signals. The image is evaluated on the basis of the picture image signal obtained at this position to detect the focus.
    Type: Grant
    Filed: November 27, 1979
    Date of Patent: November 17, 1981
    Assignee: Canon Kabushiki Kaisha
    Inventors: Toshio Sakane, Kazuya Hosoe, Takao Kinoshita, Tokuichi Tsunekawa, Takashi Kawabata
  • Patent number: 4299462
    Abstract: By providing a liquid crystal cell nearly at the position of the clear vision of the view finder optical system together with a means for masking the display part of the liquid crystal cell the noise appearing on the boundary between the display part and the object view field is eliminated while the invasion of dusts is avoided, whereby further by means of the liquid crystal cell the alarm for the improper exposure, the alarm of the consumption of the power source battery and so on are displayed besides the photographic informations.
    Type: Grant
    Filed: August 7, 1978
    Date of Patent: November 10, 1981
    Assignee: Canon Kabushiki Kaisha
    Inventors: Ryoichi Suzuki, Seiichi Matsumoto, Takashi Amikura, Tokuichi Tsunekawa, Takashi Uchiyama
  • Patent number: RE31207
    Abstract: A leak current suppressing printed circuit board in which the input circuit is so designed that between the input terminals a light sensing photoelectric converting element operating in the current mode is connected. The input is guarded by means of the circuit net, whose potential is same as that at the input terminal of the inverting input circuit or the non-inverting input circuit of the high input impedance operation amplifier.
    Type: Grant
    Filed: July 17, 1979
    Date of Patent: April 12, 1983
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tokuichi Tsunekawa, Tetsuya Taguchi