Patents by Inventor Yukio Maekawa

Yukio Maekawa 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: 4946771
    Abstract: Photographic materials which comprise novel color photographic couplers are provided. The silver halide color photographic material is improved in sharpness and prevention against the mixing of colors.
    Type: Grant
    Filed: September 28, 1989
    Date of Patent: August 7, 1990
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yukio Maekawa, Tsumoru Hirano
  • Patent number: 4943824
    Abstract: The present invention relates to a device for measuring object distance or an in-focus position used for a camera in which the object distance of focus adjusting condition are measured in a plurality of distance measuring areas in the photographing scene. The device is so constructed as to judge a main object from weight data in correspondence not only with the object distance of each distance measuring area but with the position thereof in the photographing scene. Further, when there is an object nearer than a predetermined distance, the main object is judged from whether the object has a size larger than a predetermined size in the photographing scene. Furthermore, it is judged from the difference between the object distances of adjacent distance measuring areas whether the objects are the same object.
    Type: Grant
    Filed: November 10, 1988
    Date of Patent: July 24, 1990
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Takayuki Nabeshima, Toru Matsui, Yukio Maekawa
  • Patent number: 4891307
    Abstract: A silver halide photographic material is disclosed. The material is comprised of a support having thereon at least one silver halide emulsion layer, wherein at least one of the silver halide emulsion layer and another constituent layer contains a fluorine-containing nonionic surface active agent, a fluorine-containing ionic surface active agent and a fluorine-free nonionic surface active agent.
    Type: Grant
    Filed: June 13, 1989
    Date of Patent: January 2, 1990
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yasuo Mukunoki, Yukio Maekawa, Shuzo Suga
  • Patent number: 4891306
    Abstract: A static-inhibited photographic light-sensitive material is provided by incorporating a fluorine-containing block polymer derived from a polymerizable hydrophobic monomer containing at least one fluorine atom and a polymerizable hydrophilic monomer, as an antistatic agent in at least one layer thereof. Unlike known antistatic agents and methods, the use of the above antistatic agent does not adversely affect the photographic characteristics, antitack property, marring resistance, etc., of the photographic light-sensitive material.
    Type: Grant
    Filed: November 14, 1988
    Date of Patent: January 2, 1990
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Shigeki Yokoyama, Yukio Maekawa
  • Patent number: 4878079
    Abstract: A focus detecting device capable of correcting an error, between an in-focus position of a photographic lens detected by a focus detecting means and an image field position affording the best image. Focus detection is made using plural focus detecting areas provided on and off the optical axis of the photographic lens, to obtain an in-focus position. Then, the thus-obtained in-focus position of the photographic lens is corrected using an appropriate correction value out of those preset and stored in a ROM in the lens according to whether the focus detecting area used in the focus detection is an axial or off-axial area, or according to the focal length of the photographic lens as well as the photographing mode. And the photographic lens is thereby set to the best image field position.
    Type: Grant
    Filed: August 1, 1988
    Date of Patent: October 31, 1989
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Masataka Hamada, Toshihiko Karasaki, Toru Matsui, Yukio Maekawa
  • Patent number: 4864341
    Abstract: A mount arrangement for a photographic camera which is capable of automatic diaphragm control and automatic focusing includes electrical contacts for transmission of electrical signals between a camera body and an interchangeable lens unit, and mechanical transmission members for the automatic diaphragm control and the automatic focusing and positioning member and recess on and at inner periphery of mount members of the camera body and the lens unit so as not to interfere with each other during the start and the course of the mounting of the lens unit onto the camera body through a bayonet mount device.
    Type: Grant
    Filed: April 20, 1988
    Date of Patent: September 5, 1989
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Yukio Maekawa, Tsuneyo Metabi, Masatake Niwa
  • Patent number: 4847186
    Abstract: A silver halide photographic light-sensitive material comprising a support and at least one silver halide emulsion layer, wherein at least one of said emulsion layers or another layers which constitutes said material contains a surface active agent represented by the following general formula: ##STR1## wherein Rf represents a saturated or unsaturated hydrocarbon group having 3 to 24 carbon atoms wherein all or a part of hydrogen atoms is substituted by a fluorine atom, R.sub.1 represents a substituted or unsubstituted saturated or unsaturated hydrocarbon group having 4 to 24 carbon atoms, A represents a trivalent bonding group, B represents a divalent group having an ether bond, D represents a hydrophilic group, and n represents an integer of 2 to 100.
    Type: Grant
    Filed: June 1, 1987
    Date of Patent: July 11, 1989
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yasuo Mukunoki, Yukio Maekawa
  • Patent number: 4768052
    Abstract: A focus detecting device capable of correcting an error, between an in-focus position of a photographic lens detected by a focus detecting means and an image field position affording the best image. Focus detection is made using plural focus detecting areas provided on and off the optical axis of the photographic lens, to obtain an in-focus position. Then, the thus-obtained in-focus position of the photographic lens is corrected using an appropriate correction value out of those preset and stored in a ROM in the lens according to whether the focus detecting area used in the focus detection is an axial or off-axial area, or according to the focal length of the photographic lens as well as the photographing mode. And the photographic lens is thereby set to the best image field position.
    Type: Grant
    Filed: August 14, 1987
    Date of Patent: August 30, 1988
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Masataka Hamada, Toshihiko Karasaki, Toru Matsui, Yukio Maekawa
  • Patent number: 4748467
    Abstract: A mount arrangement for a photographic camera which is capable of automatic diaphragm control and automatic focusing includes electrical contacts for transmission of electrical signals between a camera body and an interchangeable lens unit, and mechanical transmission members for the automatic diaphragm control and the automatic focusing and positioning member and recess on and at inner periphery of mount members of the camera body and the lens unit so as not to interfere with each other during the start and the course of the mounting of the lens unit onto the camera body through a bayonet mount device.
    Type: Grant
    Filed: July 31, 1986
    Date of Patent: May 31, 1988
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Yukio Maekawa, Tsuneyo Metabi, Masatake Niwa
  • Patent number: 4722885
    Abstract: A photographic material is described, comprising at least one layer containing at least one of (i) a polymer of a compound represented by formula (I) ##STR1## wherein R.sup.1 represents a hydrogen atom or an alkyl group having from 1 to 6 carbon atoms,L represents a divalent organic linking group,A represents a divalent organic linking group derived from a polymerizable monomer unit,n represents an average degree of polymerization and is a number of at least 2, andY represents a monovalent organic bonding groupand (ii) a copolymer of the compound represented by formula (I) with a copolymerizable ethylenically unsaturated monomer.
    Type: Grant
    Filed: March 11, 1985
    Date of Patent: February 2, 1988
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Shigeki Yokoyama, Junichi Yamanouchi, Masakazu Yoneyama, Yukio Maekawa
  • Patent number: 4712871
    Abstract: A positioning mechanism for positioning an auxiliary optical device relative to a main optical device, and the auxiliary optical device. Thje positioning mechanism includes a positioning member and a positioning recess which are provided on one and the other of the main and auxiliary optical devices, respectively so as to be engaged with each other with a clearance. Each of the positioning member and the positioning recess includes a leding side face portion and a trailing side face portion being opposite to and in alignment with the leading side face portion in a direction of relative movement of the main and auxiliary optical devices. The trailing side face portions of the positioning member and the positioning recess have a configuration which allows the trailing side face portions not to contact with each other when the relative movement is effected at a speed faster than a predetermined speed.
    Type: Grant
    Filed: July 17, 1985
    Date of Patent: December 15, 1987
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Junichi Tanii, Yukio Maekawa
  • Patent number: 4659203
    Abstract: An interchangeable lens unit is detachably attachable to a camera main body through an improved bayonet arrangement which includes three sets of corresponding bayonet claws, one of the corresponding bayonet claws of each set being provided on a mount member of the lens unit and the other on a mount member of the camera main body. The bayonet claws of the three sets are formed, in mutual dimension and dispositions thereof, such that the corresponding bayonet claws of one of the sets engage one another at an upper peripheral part of the mount members immediately above the center of the mount members and the corresponding bayonet claws of the remaining two sets engage one another respectively at lateral side peripheral parts of the mount members diametrically opposite to one another with respect to the center of the mount members in the lateral direction, when the camera main body and the lens unit attached thereto are viewed from their front with the camera main body held in a normal erect state.
    Type: Grant
    Filed: August 28, 1984
    Date of Patent: April 21, 1987
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Masatake Niwa, Yukio Maekawa
  • Patent number: 4637704
    Abstract: An exchangeable lens to be mounted on a camera body by the rotation of the lens barrel is provided with a plurality of terminals arranged circularly along the circumference of the lens barrel about the optical axis of the lens barrel and are connected to a CMOS circuit in the lens. The terminals include a power supply terminal and a ground terminal through which electric power is supplied from the camera and a signal terminal through which a signal is transmitted between the camera body and the lens. The power supply terminal and the ground terminal are arranged to come into contact with their corresponding camera terminals in advance of the signal terminals when the lens is rotated to mount it on the camera body.
    Type: Grant
    Filed: November 19, 1985
    Date of Patent: January 20, 1987
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Toshihiko Ishimura, Yukio Maekawa
  • Patent number: 4623614
    Abstract: A silver halide photographic light-sensitive material is described, comprising a support having thereon at least one silver halide photographic light-sensitive emulsion layer, said photographic light-sensitive material further comprising at least one light-insensitive surface layer on at least one side thereof, at least one of said surface layer or layers comprising a graft polymer or copolymer having a silicone unit, and at least one of said surface layer or layers and a layer or layers adjacent to the surface layer or layers comprising an antistatic agent.The silver halide light-sensitive material has good antistatic property and reduced sliding friction without giving bad influences on the photographic properties; has good antistatic property and lubricity after development processing; has improved antistatic property and lubricity without reducing the coating properties at the production of the photographic light-sensitive material; and forms no scum during development processing.
    Type: Grant
    Filed: August 7, 1985
    Date of Patent: November 18, 1986
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Masakazu Yoneyama, Yukio Maekawa, Shigeki Yokoyama, Junichi Yamanouchi
  • Patent number: 4622288
    Abstract: A photographic light-sensitive material containing a fluorine-containing graft polymer is disclosed. The graft polymer is derived from a polymerizable hydrophobic fluorine-containing monomer containing at least one fluorine atom and a polymerizable hydrophilic monomer, and optionally, a third polymerizable hydrophobic monomer containing no fluorine atom. The material has an improved antistaticity.
    Type: Grant
    Filed: March 11, 1985
    Date of Patent: November 11, 1986
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Shigeki Yokoyama, Junichi Yamanouchi, Masakazu Yoneyama, Yukio Maekawa
  • Patent number: 4620780
    Abstract: A mount arrangement for a photographic camera which is capable of automatic diaphragm control and automatic focusing includes electrical contacts for transmission of electrical signals between a camera body and an interchangeable lens unit, and mechanical transmission members for the automatic diaphragm control and the automatic focusing and positioning member and recess on and at inner periphery of mount members of the camera body and the lens unit so as not to interefere with each other during the start and the course of the mounting of the lens unit onto the camera body through a bayonet mount device.
    Type: Grant
    Filed: June 25, 1985
    Date of Patent: November 4, 1986
    Assignee: Minolta Camera Kabushiki Kaisha
    Inventors: Yukio Maekawa, Tsuneyo Metabi, Masatake Niwa
  • Patent number: 4618575
    Abstract: A silver halide photographic light-sensitive material is described, comprising a hydrophilic organic colloid layer, wherein the hydrophilic organic colloid layer contains at least one compound represented by ##STR1## wherein R.sub.1 represents a substituted or unsubstituted alkyl or aromatic group;R.sub.2 represents a hydrogen atom or ##STR2## wherein L.sub.4 represents a divalent bonding group, and R.sub.5 represents a hydrogen atom or a substituted or unsubstituted alkyl or aromatic group;R.sub.3 and R.sub.4 each represents a hydrogen atom, or a substituted or unsubstituted alkyl group;L.sub.1 represents a divalent bonding group;L.sub.2 and L.sub.3 each represents a single bond or a divalent or trivalent bonding group;n and n' each represents an integer of 1 or 2;A represents a repeating unit resulting from polymerization of an ethylenically unsaturated monomer copolymerizable with monomers constituting the units ##STR3## wherein X.sub.1 and X.sub.
    Type: Grant
    Filed: April 3, 1985
    Date of Patent: October 21, 1986
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Yukio Maekawa, Yasuo Mukunoki
  • Patent number: 4558001
    Abstract: A silver halide photographic light-sensitive material is disclosed wherein at least one gelatin-containing layer thereof contains at least one nonionic surface active agent having reactive groups, the agent being represented by the following formula (I), (II) or (III) ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 ' each represents a hydrogen atom or a halogen atom, or an unsubstituted or substituted alkyl, aryl, alkoxyl, acyl, amido, sulfonamido, carbamoyl, or sulfamoyl group; R.sub.3 and R.sub.4 each represents a hydrogen atom, an unsubstituted or substituted alkyl or aryl group, or a heteroaromatic ring, R.sub.3 and R.sub.4 may combine to form a ring; m.sub.1 and m.sub.2, which may be the same or different, are 2 to 40, each representing the average degree of polymerization of ethylene oxide; m.sub.3 is 0 or 1; and n.sub.1 and n.sub.2 represent the ratios in the copolymer, and n.sub.1 is 1 to 100 and n.sub.2 is 0 to 99, the sum thereof being 100.
    Type: Grant
    Filed: April 13, 1984
    Date of Patent: December 10, 1985
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Shigeki Yokoyama, Hisashi Okamura, Yukio Maekawa, Hiroshi Kawasaki
  • Patent number: 4536071
    Abstract: A mount arrangement for a photographic camera which is capable of automatic diaphragm control and automatic focusing includes electrical contacts for transmission of electrical signals between a camera body and an interchangeable lens unit, and mechanical transmission members for the automatic diaphragm control and the automatic focusing and positioning member and recess on and at inner periphery of mount members of the camera body and the lens unit so as not to interfere with each other during the start and the course of the mounting of the lens unit onto the camera body through a bayonet mount device.
    Type: Grant
    Filed: August 30, 1984
    Date of Patent: August 20, 1985
    Inventors: Yukio Maekawa, Tsuneyo Metabi, Masatake Niwa
  • Patent number: 4518354
    Abstract: A silver halide photographic light-sensitive material is disclosed. The photographic material is comprised of a support base, a silver halide emulsion layer and an antistatic layer. The antistatic layer contains a nonionic surface active agent having two polyoxyethylene chains in a molecule represented by the formula (I): ##STR1## wherein R.sub.1 and R.sub.3 each represents a substituted or unsubstituted alkyl group, an aryl group, an alkoxy group, a halogen atom, an acyl group, an amido group, a sulfonamido group, a carbamoyl group or a sulfamoyl group, R.sub.2 and R.sub.4 each represents a hydrogen atom, a substituted or unsubstituted alkyl group, an aryl group, an alkoxy group, a halogen atom, an acyl group, an amido group, a sulfonamido group, a carbamoyl group or a sulfamoyl group, R.sub.5 represents a hydrogen atom, a methyl group or an .alpha.-furyl group, and m and n independently represents an average degree of polymerization of ethylene oxide, which is 2 to 40.
    Type: Grant
    Filed: May 23, 1983
    Date of Patent: May 21, 1985
    Assignee: Fuji Photo Film Co., Ltd.
    Inventors: Shigeki Yokoyama, Akira Hibino, Yukio Maekawa, Hiroshi Kawasaki