Patents Assigned to Asahi Kogaku Kabushiki Kaisha
  • Patent number: 5442481
    Abstract: A real image type of finder optical system, provided separately from a photographing optical system. A real image is formed by an objective optical system and is observed through an ocular optical system. The objective optical system includes at least one lens that is made of synthetic resin and has at least one lens surface coated with an anti-reflection material.
    Type: Grant
    Filed: August 11, 1993
    Date of Patent: August 15, 1995
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventor: Sachio Hasushita
  • Patent number: 5371630
    Abstract: A zoom lens system includes, in order from the object side, a first lens unit that remains fixed during zooming and which has a positive power, a second lens unit that has a zooming capability, that moves during zooming and that has a negative power, a third lens unit that has a capability of compensating for the position of the focal point, that moves during zooming and that has a negative power, and a fourth lens unit that has an imaging capability, that remains fixed during zooming and that has a positive power, said fourth lens unit comprising a first sub-unit that comprises, in order from the object side, a positive lens element, a positive lens element and a negative lens element and that has a positive overall power, and a second sub-unit that comprises, in order from the object side, a positive lens element, a negative lens element and a positive lens element and that has a positive overall power. The zoom lens system satisfies the specified conditions.
    Type: Grant
    Filed: July 23, 1992
    Date of Patent: December 6, 1994
    Assignees: Asahi Kogaku Kabushiki Kaisha, Asahi Seimitsu Kabushiki Kaisha
    Inventors: Takayuki Ito, Yasuyuki Sugano
  • Patent number: 5363165
    Abstract: A power zoom lens having a zooming lens unit which is movable in an optical axis direction to vary a focal length thereof and which is detachably mounted to a camera body. The power zoom lens includes a drive mechanism for driving the zooming lens unit, a detecting device for detecting a focal length of the power zoom lens, a memory device for storing the focal length detected by the detecting device, and a control device for controlling the drive mechanism until the focal length stored in the memory device is obtained.
    Type: Grant
    Filed: May 21, 1992
    Date of Patent: November 8, 1994
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventors: Masahiro Kawasaki, Hiroyuki Takahashi, Yoshinari Tanimura
  • Patent number: 5345288
    Abstract: An electronically controlled camera is provided capable of being operated in an automatic release mode in which a plurality of shootings can be automatically executed. The camera includes a device for setting the number of shootings to be executed and a device for automatically setting the internal time between each shooting in accordance with the number of shootings set to be executed.
    Type: Grant
    Filed: July 2, 1992
    Date of Patent: September 6, 1994
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventors: Takeo Kobayashi, Yasushi Tabata, Norio Numako, Katsutoshi Nagai
  • Patent number: 5329935
    Abstract: A sheathed endoscope has a flexible elongate insert part and a sheath that is removably fitted over the insert part. The sheathed endoscope comprises a distal end part that is provided at the distal end of the insert part, a distal end cover that is provided at the distal end of the sheath and that is removably fitted over the distal end part, and a lock device that is provided on the distal end cover so as to be engageable with the distal end part. The lock device is disengaged from the distal end part by deforming the distal end cover so that the lock device moves radially outward. A sheath for a sheathed endoscope is provided and is removably fitted over a flexible elongate insert part of the endoscope.
    Type: Grant
    Filed: May 10, 1993
    Date of Patent: July 19, 1994
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventor: Nagashige Takahashi
  • Patent number: 5327183
    Abstract: A camera having a flash, a focal plane shutter, a mechanism for changing a size of a film frame by changing a size of an aperture of the camera, and a mechanism for setting a flash synchronized shutter speed. The focal plane shutter has a leading-shutter-curtain and a trailing-shutter-curtain, which are moved in a vertical direction of the aperture to thereby open and close the aperture. The changing mechanism changes the aperture size in the vertical direction to obtain a panoramic style frame and a standard frame. The setting mechanism sets the flash synchronized shutter speed to a high speed when the aperture is changed to a panoramic style frame having a vertical size which is smaller than that of a standard frame. The output of the flash can be started at a time at which a trailing edge of the leading-shutter-curtain passes a lower side of the panoramic style frame.
    Type: Grant
    Filed: May 26, 1992
    Date of Patent: July 5, 1994
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventor: Hiroshi Kurei
  • Patent number: 5305068
    Abstract: A printer, for printing on continuous recording paper, includes tractors disposed in the recording paper feed path of the printer, with each of the tractors circumferentially travelling in synchronism with movement of the continuous recording paper when the tractors engage feed holes of the continuous paper. When no printing operation is performed, travel of the tractors can be prevented by operation of an electromagnetic clutch, or a combination of one way clutches. Further, the printer uses an electrophotographic method wherein when no printing operation is performed, a transfer charger or fixing roller can be retracted from an operational position. A lever, associated with movement of the transfer charge or fixing roller, is pressed against and locked with the pulley fixed to the rotating shaft of each of the tractors to thereby prohibit the movement of the tractor.
    Type: Grant
    Filed: April 23, 1992
    Date of Patent: April 19, 1994
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventors: Tsutomu Sato, Masatoshi Takano, Taizo Saito, Hiroyuki Yamaguchi
  • Patent number: 5223877
    Abstract: A camera system includes a camera body, and an interchangeable lens that is detachably mounted to the camera body. The interchangeable lens includes an input/output circuit for performing input/output information relative to the camera body and a timing circuit outputs a clock signal. The camera body includes an information processing circuit for performing data communication relative to the input/output circuit on the basis of the clock signal outputted from said timing circuit.
    Type: Grant
    Filed: February 15, 1991
    Date of Patent: June 29, 1993
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventors: Masahiro Kawasaki, Hiroyuki Takahashi, Shigeru Iwamoto
  • Patent number: 5191369
    Abstract: A photographing light quantity controller for an endoscope, which is used to control the quantity of illuminating light when a photograph is to be taken through the endoscope. The photographing light quantity controller comprises a device for supplying light for illuminating an object to the endoscope, a device for detecting a quantity of light that is reflected from the object and for outputting a signal in accordance with the detected quantity of light, and a device for amplifying the signal, with the amplifying device having a plurality of amplification factors which can be selected as desired. A photographing light quantity control device is provided for controlling the quantity of illuminating light that is supplied to the endoscope when a photographing operation is conducted, on the basis of the output signal from the amplifying device.
    Type: Grant
    Filed: August 21, 1991
    Date of Patent: March 2, 1993
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventors: Katsuhiko Furuya, Masaaki Nakasima, Takayuki Enomoto, Tadashi Takahashi
  • Patent number: 5170294
    Abstract: A method of controlling the focusing of a zoom lens which has a plurality of lens groups including at least one focusing lens group, wherein an amount of deviation from focus caused by a zoom operation is corrected by movement of the focusing lens group. The method includes setting a reference object distance, at which no deviation from focus occurs during zooming of the zoom lens, at a finite object distance, such that the amount of movement of the focusing lens group necessary to effect focusing is determined based upon a reference position corresponding to a position of the focusing lens group at the reference object distance, in accordance with focal length data and object distance data. The zoom lens assembly includes a stationary lens barrel and a rotatable cam ring which is supported on the stationary lens barrel for movement in the direction of the optical axis while being rotated, and which includes at least two cam grooves.
    Type: Grant
    Filed: October 13, 1989
    Date of Patent: December 8, 1992
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventors: Keisuke Haraguchi, Yukio Takaoka, Shinsuke Kohmoto, Takeo Kobayashi, Takayuki Ito, Tomoaki Kobayashi
  • Patent number: 5046351
    Abstract: A mold for forming a groove in a tube includes a split round bar having a groove extending in a substantially straight line along an axis thereof. The two halves of the split round bar are in contact with each other only at a pint at the bottom of the groove, so that the two halves may pivot with respect to each other about the contact point. A spacer bar is removably clamped between opposed inner surfaces of the two halves of the split round bar. When the spacer is removed, the groove in the round bar is slightly enlarged to provide clearance between the tube and each side wall of the groove to enable the round bar to be easily removed from the tube.
    Type: Grant
    Filed: March 30, 1990
    Date of Patent: September 10, 1991
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventors: Nagashige Takahashi, Teruo Ouchi
  • Patent number: 5005087
    Abstract: A signal processor for an AF video signal in an electronically controlled camera, including: a photosensor of the self-scanning type having an electric charge accumulating part for accumulating electric charge therein which corresponds to object brightness, an exposure monitor for accumulating electric charge therein which corresponds to the amount of signal electric charge accumulated in the electric charge accumulating part, and a dark charge monitor for accumulating dark charge therein.
    Type: Grant
    Filed: August 22, 1989
    Date of Patent: April 2, 1991
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventors: Noboru Suzuki, Shigeo Toji, Yukio Uenaka
  • Patent number: 4897250
    Abstract: A process for producing a calcium phosphate comprising the steps of (a) dissolving at least one member selected from the group consisting of calcium hydroxide and calcium oxide in water with at least one member selected from the group consisting of a sugar, a sugar alcohol, and a polyhydric alcohol; (b) and adding phosphoric acid to the solution obtained to precipitate a calcium phosphate.
    Type: Grant
    Filed: January 25, 1989
    Date of Patent: January 30, 1990
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventor: Masaya Sumita
  • Patent number: 4829332
    Abstract: An optical system for use in a focus detecting apparatus has a photographing lens for forming an image of an object, a condenser lens disposed behind, with respect to the photographic lens, a plane corresponding to a photographing film surface, and a pair of split optical elements located behind the condenser lens for splitting the image of the object. The split optical elements are symmetrical with respect to a meridional plane of the condenser lenses. Using a line sensor, a relative positional shift of the images is detected by the optical system to determine a focal position. The optical system has a sufficiently large spherical aberration that the diameter of the minimum circle of confusion at the maximum contrast position is larger than the width of one bit of the line sensor.
    Type: Grant
    Filed: March 21, 1988
    Date of Patent: May 9, 1989
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventor: Osamu Shindo
  • Patent number: 4793698
    Abstract: A telephoto lens system, both compact and capable of close-in focusing, comprising, in order from the object side, a first lens unit of positive power, a second lens unit of negative power, a third lens unit of either power and a fourth lens unit of positive power. There are additionally imposed five numerical conditions on the focal lengths of the lens units, their separation and their displacement. The second and third lens units are displaced by differing amounts for focusing.
    Type: Grant
    Filed: April 2, 1987
    Date of Patent: December 27, 1988
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventor: Hiroyuki Hirano
  • Patent number: 4502775
    Abstract: A camera flash photographing control device having a signal conversion element which generates step wave voltage for which a signal level is gradually varied as time passes, by the operation of a counter which receives a pulse signal. A signal conversion element is operated as an A-D converter in which digital signal output which corresponds to a required signal level is obtained by converting both analogue signals of luminance information of an object and iris information of a photographing lens into said required signal level at the time of light measurement before shutter release. A signal conversion element is operated as a digital-analogue converter in which analogue signal output which corresponds to a pulse signal is obtained by converting the digital signal input of film sensitivity information into a required pulse signal at the time of shutter control after shutter release.
    Type: Grant
    Filed: February 8, 1983
    Date of Patent: March 5, 1985
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventor: Yoshifumi Kuroki
  • Patent number: 4240700
    Abstract: The present invention relates to a wide angle zoom lens system having a high variation ratio and a zooming range between a wide angle and a semi-telescopic angle, with the zoom ratio being approximately 2.3 to 3.0 times. The present invention provides the wide variation especially at the wide angle portion of the zoom. The present invention comprises, in order from the object side, a first lens group I having a positive focal length f.sub.I, a second lens group II (also referred to as a first variator lens group) having a negative focal length f.sub.II, and a third lens group III (also referred to as a second variator lens group) having a positive focal length f.sub.III. The present invention may include a lens group III' having a positive focal length f.sub.III'. The lens group III' may be disposed along the optical axis either at the image side or at the object side of the third lens group III. The lens group III' is unmovable during zooming.
    Type: Grant
    Filed: July 28, 1978
    Date of Patent: December 23, 1980
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventors: Ryota Ogawa, Sadao Okudaira, Satoru Tachihara
  • Patent number: 3978503
    Abstract: A rotatable member overlying a relatively fixed member has a quadrilateral window corresponding to a similar quadrilateral window within the fixed member through which passes the pivot axis of the rotating member. The rotating member controls movement of a pair of shield blades movable towards and away from each other from opposite sides of the window within the fixed member such that light shielding of the optical path through the fixed member window is effected partially by overlapping of the window frame portion of the rotating member relative to the window frame portion of the fixed member and the remaining portion of the fixed window is covered by the shield blades.
    Type: Grant
    Filed: October 1, 1975
    Date of Patent: August 31, 1976
    Assignee: Asahi Kogaku Kabushiki Kaisha
    Inventor: Tetsuji Shono