Patents by Inventor Toshifumi Masaki

Toshifumi Masaki 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).

  • Publication number: 20100085538
    Abstract: A single-plate image pickup element picks up an eye fundus image. A tricolor separation color filter includes R, G, and B filter elements arranged in a mosaic so as to correspond to the pixels of the image pickup element. Each virtual pixel value of color image data is calculated from light detection data of adjacent pixels. Thus, image data of a color still image is generated. The R filter elements transmit near-infrared light. Each virtual pixel value is calculated from light detection data of pixels corresponding to B or G filter elements that are adjacent to the R filters and have sensitivity to near-infrared light. Thus, image data of a near-infrared light monochrome moving image is generated.
    Type: Application
    Filed: September 24, 2009
    Publication date: April 8, 2010
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Toshifumi Masaki, Toshiaki Okumura, Shinya Tanaka
  • Patent number: 7553282
    Abstract: A non-contact tonometer changes a reference signal used for determining reliability of a signal indicating deformation of a cornea based on the reflectance of the cornea of an eye to be examined. Thus, the non-contact tonometer can perform stable measurement irrespective of the reflectance of the cornea of the eye to be examined.
    Type: Grant
    Filed: October 20, 2003
    Date of Patent: June 30, 2009
    Assignee: Canon Kabushiki Kaisha
    Inventor: Toshifumi Masaki
  • Patent number: 7478909
    Abstract: In an ophthalmologic apparatus, the coordinates of three illuminated spots on a cornea-reflected image calculated from a front eye part image picked up by a two-dimension image pickup element and a pupil diameter are calculated, and the position of the centroid of the pupil is calculated from the front eye part image. When the pupil diameter is smaller than a predetermined value, alignment is effected from the shift from the center of the pupil, and when the pupil diameter is larger than the predetermined value, alignment is effected on the basis of the shift amounts from the illuminated spots on the cornea-reflected image. Also, a controlling method is changed over by the difference between the positions of the illuminated spots on the cornea-reflected image and the position of the centroid of the pupil. Also, the tolerance level of alignment is varied by the size of the pupil diameter.
    Type: Grant
    Filed: February 3, 2004
    Date of Patent: January 20, 2009
    Assignee: Canon Kabushiki Kaisha
    Inventor: Toshifumi Masaki
  • Patent number: 7258443
    Abstract: In order to accurately align an eye examining portion with the center of the pupil, (a) the interval d between illumination light source images PL and PR is an interval obtained when the operation distance has been properly position-aligned by other alignment means. (b) shows an interval d1 in a state in which the operation distance is longer than to a proper position, and (c) shows an interval d2 in a state in which the operation distance is shorter than the proper position. Even if the operation distance fluctuates when position alignment is effected with the center of the pupil, whereby the interval becomes d1 and d2 as shown in (b) and (c), a measuring portion is moved in front to rear direction and is made coincident with the reference interval d, as shown in (a), whereby a proper operation distance is obtained.
    Type: Grant
    Filed: June 13, 2005
    Date of Patent: August 21, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventor: Toshifumi Masaki
  • Publication number: 20050275804
    Abstract: In order to accurately align an eye examining portion with the center of the pupil, (a) the interval d between illumination light source images PL and PR is an interval obtained when the operation distance has been properly position-aligned by other alignment means. (b) shows an interval d1 in a state in which the operation distance is longer than to a proper position, and (c) shows an interval d2 in a state in which the operation distance is shorter than the proper position. Even if the operation distance fluctuates when position alignment is effected with the center of the pupil, whereby the interval becomes d1 and d2 as shown in (b) and (c), a measuring portion is moved in front to rear direction and is made coincident with the reference interval d, as shown in (a), whereby a proper operation distance is obtained.
    Type: Application
    Filed: June 13, 2005
    Publication date: December 15, 2005
    Inventor: Toshifumi Masaki
  • Publication number: 20040156019
    Abstract: In an ophthalmologic apparatus, the coordinates of three illuminated spots on a cornea-reflected image calculated from a front eye part image picked up by a two-dimension image pickup element and a pupil diameter are calculated, and the position of the centroid of the pupil is calculated from the front eye part image. When the pupil diameter is smaller than a predetermined value, alignment is effected from the shift from the center of the pupil, and when the pupil diameter is larger than the predetermined value, alignment is effected on the basis of the shift amounts from the illuminated spots on the cornea-reflected image. Also, a controlling method is changed over by the difference between the positions of the illuminated spots on the cornea-reflected image and the position of the centroid of the pupil. Also, the tolerance level of alignment is varied by the size of the pupil diameter.
    Type: Application
    Filed: February 3, 2004
    Publication date: August 12, 2004
    Inventor: Toshifumi Masaki
  • Patent number: 6733129
    Abstract: An aligning method for an ophthalmologic apparatus including a measurement optical system for measuring the eyes of an object to be examined and an illumination system for illuminating the eyes with extrinsic eye light is disclosed. When a reflected cornea image can be detected by irradiating an eye of the object with alignment light, alignment of the measurement optical system is executed on the basis of the reflected cornea image. If no reflected cornea image of the alignment light can be detected, a reflected cornea image formed by the extrinsic eye light is detected, and alignment of the measurement optical system is executed on the basis of the reflected cornea image formed by the extrinsic eye light. Thereafter, the reflected cornea image is detected again.
    Type: Grant
    Filed: March 26, 2002
    Date of Patent: May 11, 2004
    Assignee: Canon Kabushiki Kaisha
    Inventor: Toshifumi Masaki
  • Publication number: 20040087849
    Abstract: A non-contact tonometer changes a reference signal used for determining reliability of a signal indicating deformation of a cornea based on the reflectance of the cornea of an eye to be examined. Thus, the non-contact tonometer can perform stable measurement irrespective of the reflectance of the cornea of the eye to be examined.
    Type: Application
    Filed: October 20, 2003
    Publication date: May 6, 2004
    Inventor: Toshifumi Masaki
  • Publication number: 20020159028
    Abstract: An aligning method for an ophthalmologic apparatus including a measurement optical system for measuring the eyes of an object to be examined and an illumination system for illuminating the eyes with extrinsic eye light is disclosed. When a reflected cornea image can be detected by irradiating an eye of the object with alignment light, alignment of the measurement optical system is executed on the basis of the reflected cornea image. If no reflected cornea image of the alignment light can be detected, a reflected cornea image formed by the extrinsic eye light is detected, and alignment of the measurement optical system is executed on the basis of the reflected cornea image formed by the extrinsic eye light. Thereafter, the reflected cornea image is detected again.
    Type: Application
    Filed: March 26, 2002
    Publication date: October 31, 2002
    Inventor: Toshifumi Masaki
  • Patent number: 5822034
    Abstract: This specification discloses an ophthalmologic apparatus for executing an eye examination on an eye to be examined. The ophthalmologic apparatus is provided with an eye examination unit, an alignment drive system for driving the eye examination unit to thereby execute the alignment between the eye examination unit and the eye to be examined, a time measuring portion, and a control system for causing the alignment drive system to drive the eye examination unit on the basis of the output of the time measuring portion so as to return the eye examination unit to an eye examination waiting position.
    Type: Grant
    Filed: June 25, 1996
    Date of Patent: October 13, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Satoshi Shimashita, Takashi Masuda, Yoshimasa Hamano, Koji Uchida, Toshifumi Masaki