Patents by Inventor Toshifumi Mihashi
Toshifumi Mihashi 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).
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Patent number: 11109754Abstract: Provided is an ophthalmic measurement device with which it is possible to obtain an area in which a measurement can be taken without moving an optical system. With reference to an optical path length of an illumination optical system with which light is focused on the eyeground when the refraction value is 0 D, the positions of two light sources are set to achieve a setting in which the optical path length becomes slightly shorter. By doing so, it is possible to cope with measurement of refractive properties in a large area without employing structures that allow a lens system of the illumination optical system and the light sources thereof to be moved. In addition, by selecting one of the two light sources so that a clearer Hartmann image can be obtained, it is possible to further increase the precision of the refractive properties to be measured.Type: GrantFiled: January 24, 2018Date of Patent: September 7, 2021Assignee: TOPCON CORPORATIONInventor: Toshifumi Mihashi
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Publication number: 20190365222Abstract: Provided is an ophthalmic measurement device with which it is possible to obtain an area in which a measurement can be taken without moving an optical system. With reference to an optical path length of an illumination optical system with which light is focused on the eyeground when the refraction value is 0 D, the positions of two light sources are set to achieve a setting in which the optical path length becomes slightly shorter. By doing so, it is possible to cope with measurement of refractive properties in a large area without employing structures that allow a lens system of the illumination optical system and the light sources thereof to be moved. In addition, by selecting one of the two light sources so that a clearer Hartmann image can be obtained, it is possible to further increase the precision of the refractive properties to be measured.Type: ApplicationFiled: January 24, 2018Publication date: December 5, 2019Applicant: TOPCON CORPORATIONInventor: Toshifumi MIHASHI
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Publication number: 20180085212Abstract: An ocular function assistance device of an embodiment includes an actuator, a controller, and an information input unit. The ocular function assistance device is used for assisting an ocular function. The actuator receives electricity and operates for providing a predefined ocular function. The controller executes at least control of electricity supply to the actuator. The information input unit inputs biological information or condition information into the controller. The controller changes a control mode of the actuator based on the biological information or the condition information.Type: ApplicationFiled: February 22, 2016Publication date: March 29, 2018Applicant: KABUSHIKI KAISHA TOPCONInventors: Toshifumi MIHASHI, Yasufumi FUKUMA, Makoto FUJINO
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Patent number: 7850305Abstract: The object of the invention is to provide a favorable spectral characteristic that reduces variation depending on the frequency of received light intensity, and that is gentle on a subject eye. It also eliminates displacement between positions of respective spectral images of the same part even if a change in alignment occurs between the eye and apparatus with the lapse of time.Type: GrantFiled: December 2, 2005Date of Patent: December 14, 2010Assignee: Topcon CorporationInventors: Yoko Hirohara, Tatsuo Yamaguchi, Toshifumi Mihashi, Hiroyuki Aoki, Yasuko Tsuruga
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Patent number: 7806529Abstract: An eye examination apparatus 100 of the present invention comprises, a refractive power measuring section 50 for measuring refractive powers of subject eyes E of a subject in a binocular viewing state, an eye chart presenting section 30 for presenting a subjective measurement eye chart to be observed by the subject, a correcting section 40 for correcting the subject eyes by referring to data on the refractive powers measured with the refractive power measuring section 50 and using the subjective measurement eye chart presented in the eye chart presenting section 30 and an optical characteristics measuring section 10 for subjectively measuring an optical characteristic of the subject eyes E corrected or being corrected with the correcting section 40 in a state where the subject is binocularly viewing the subjective measurement eye chart.Type: GrantFiled: March 27, 2008Date of Patent: October 5, 2010Assignee: Topcon CorporationInventors: Toshifumi Mihashi, Yoko Hirohara, Mariko Kobayashi
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Patent number: 7677728Abstract: A subject is placed in a more natural state or is encouraged to blink at specified intervals to obtain a measurement result under a fixed condition, and the judgment of the degree of dry eye is facilitated. A measurement part obtains, based on a reflected light flux from a subject eye, optical characteristic data of a two-dimensional vector form representing the time course of each optical characteristic of the subject eye in an blink interval from a certain blink to a next blink with respect to the first to the nth blink intervals. An analysis part one-dimensionally arranges each of the optical characteristic data with respect to the first to the nth blink intervals measured by the measurement part, and arranges the one-dimensional arrangement of the optical characteristic in a p-th blink interval at a p column to create a two-dimensional array, and performs a principal component analysis processing on the two-dimensional array.Type: GrantFiled: March 21, 2007Date of Patent: March 16, 2010Assignee: Kabuhsiki Kaisha TopconInventors: Yoko Hirohara, Toshifumi Mihashi
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Patent number: 7677731Abstract: Scattering can be measured by using an optical system having a Hartman-Shack wave-surface sensor.Type: GrantFiled: November 15, 2007Date of Patent: March 16, 2010Assignee: Kabushiki Kaisha TopconInventors: Toshifumi Mihashi, Yoko Hirohara, Takashi Fujikado, Naoyuki Maeda
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Patent number: 7648240Abstract: An ophthalmic apparatus comprises a projection system in which a pattern member is provided with a predetermined pattern for measuring the shape of the cornea of an eye of a subject, the predetermined pattern is thereby projected on the cornea of the eye of the subject, and an optical observation system in which light flux having a shape of the predetermined pattern emitted from the projection system is reflected at the cornea of the eye of the subject, the eye of the subject is observed by the light reflected by the cornea. A surface at the eye of the subject side of the pattern member is coated with a paint having a filtering property that transmits infrared light and blocks visible light.Type: GrantFiled: March 20, 2008Date of Patent: January 19, 2010Assignee: Kabushiki Kaisha TopconInventors: Naoki Nakazawa, Koji Nakajima, Toshifumi Mihashi
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Patent number: 7635186Abstract: There is provided a Shack-Hartmann wavefront sensor which can repetitively perform a measurement at high speed and at short measurement intervals. An illuminating optical system includes a first polarizing optical member to alternately change a polarization condition to a first polarized light or a second polarized light, and illuminates a pulse light from a laser light source part to an ocular fundus of a subject eye through a first polarizing optical member. A light receiving optical system includes a second polarizing optical member to select each polarized light component of the reflected light from the subject eye illuminated according to the polarization condition of the first polarizing optical member, and a first and a second light receiving parts to alternately receive the reflected light of the selected polarized light component.Type: GrantFiled: March 2, 2007Date of Patent: December 22, 2009Assignee: Kabushiki Kaisha TopconInventors: Mariko Kobayashi, Tatsuo Yamaguchi, Toshifumi Mihashi
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Patent number: 7568800Abstract: To provide a spectroscopic fundus measuring apparatus capable of identifying each part in spectral fundus images easily and accurately based on its spectral characteristic and a measuring method therefor. A spectral fundus image measuring apparatus 1 of the present invention includes: an illumination optical system 10; a light receiving optical system 20 for photographing a series of spectral fundus images of different wavelengths; an image processing section 7 for processing the spectral fundus images; a storage section 7A; and a display section 7B. The image processing section 7 has a position correcting section 72 for correcting the series of spectral fundus images to match the positions of the same parts therein, and an image analyzing section 73 for calculating the spectral characteristic of each part in the spectral fundus images based on the series of spectral fundus images corrected in the position correcting section 72.Type: GrantFiled: June 14, 2007Date of Patent: August 4, 2009Assignee: Topcon CorporationInventors: Toshifumi Mihashi, Yoko Hirohara
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Patent number: 7566131Abstract: A refraction measuring instrument for measuring the refraction of an eye to be examined while the subject is viewing an external object in a more natural posture. A measuring light beam from a light source 21 is reflected from a mirror 25, shaped into a beam with a ring cross section, directed to a free curved surface prism 31 along an optical axis O2, reflected from a surface 31b and a beam splitting surface 31a, guided to an eye E along an optical axis O1 together with the visible light from outside the instrument, and form a ring pattern on the fundus F. The measurement beam reflected from the fundus F is received by a CCD 23 through the free curved surface prism 31 and a prism 22, and a ring pattern is imaged. A calculation control device 4 analyzes the imaged ring pattern and calculates the sphericity, the degree of astigmatism, and the astigmatic axis angle. For measurement, the subject A wears the refraction measuring instrument 1 on the head H through a wearing section 1a.Type: GrantFiled: March 31, 2004Date of Patent: July 28, 2009Assignee: Kabushiki Kaisha TopconInventor: Toshifumi Mihashi
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Patent number: 7537340Abstract: A pulse light source section outputs a plurality of pulse light according to the exposure timing of a retina imaging device. A retina illumination system illuminates the retina of an eye under measurement with the pulse light. A wavefront compensation system illuminates the eye and measures aberrations from a light reflected from the eye. The wavefront compensation system uses a wavefront compensation device and other components to compensate to cancel out measured aberrations. A retina imaging device receives a light which was reflected from the retina and of which the aberrations have been compensated for. A retina observation system forms an image of the retina on the retina imaging device with a light which was reflected and compensated. With the plurality of pulse light output from the pulse light source section, a plurality of consecutive retina images are obtained.Type: GrantFiled: April 5, 2007Date of Patent: May 26, 2009Assignee: Kabushiki Kaisha TopconInventors: Tatsuo Yamaguchi, Toshifumi Mihashi
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Patent number: 7530692Abstract: Horizontal and vertical scanning mirrors for scanning over a large angle, and horizontal and vertical compact scanning mirrors for scanning over a small angle are disposed at pupil-conjugated positions. Light is emitted from a light source to a retina, and reflected light from a broad range of the retina is accumulated by a photodetector. The accumulated light is constructed as a low-magnification retinal image by an image constructing processor. A position for picking up a high-magnification image is indicated on the basis of the constructed low-magnification retinal image. The compact scanning mirrors are rotated so that a high-magnification retinal image is achieved at the indicated pickup position. The photodetector accumulates the reflection light from the retina, and constructs the high-magnification retinal image at the pickup position indicated by the image constructing processor.Type: GrantFiled: June 14, 2007Date of Patent: May 12, 2009Assignee: Kabushiki Kaisha TopconInventors: Tatsuo Yamaguchi, Toshifumi Mihashi
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Patent number: 7527379Abstract: A first wavelength for measurement is selected from among a plurality of wavelengths. Aberrations at the first wavelength are measured with a wavefront-measurement light source having the first wavelength. A compensation optical section performs compensation so as to cancel out the measured aberrations. After the compensation, a retinal image is obtained from a retina imaging device using a retina illumination light source having the same wavelength as the wavefront-measurement light source. During image-data transfer from the retina imaging device, aberrations at a second wavelength are measured using another wavefront-measurement light source having the second wavelength. The compensation optical section performs compensation so as to cancel out the measured aberrations. After the compensation, a retinal image is obtained using another retina illumination light source having the same wavelength as the another wavefront-measurement light source.Type: GrantFiled: June 14, 2007Date of Patent: May 5, 2009Assignee: Kabushiki Kaisha TopconInventors: Tatsuo Yamaguchi, Toshifumi Mihashi
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Patent number: 7500754Abstract: Light from a light source is divided into S-polarization and P-polarization light. The P-polarization light is incident to a retinal illumination system for high-power image and the S-polarization light is incident to a retinal illumination system for low-power image. These lights are set center illumination and ring illumination by aperture diaphragms. Reflection light flux from a cornea under the high-power retina illumination light passes through the center of a perforated mirror, and thus light reflected from the retina and the perforated mirror is received through a high-power optical system to achieve an excellent retinal image having no flare. Likewise, reflection light flux from the cornea under the low-power retina illumination light is reflected from the perforated mirror, and thus light reflected from the retina and passing through the center of the hole is received through a low-power optical system to achieve an excellent retinal image having no flare.Type: GrantFiled: May 1, 2007Date of Patent: March 10, 2009Assignee: Kabushiki Kaisha TopconInventors: Tatsuo Yamaguchi, Toshifumi Mihashi
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Patent number: 7465049Abstract: A portable ophthalmic apparatus (1) according to the present invention comprises a supporting part (7) to which a cellular phone (2) having a photographing camera (5) is mounted detachably and a main body (6) which is provided with the supporting part (7) integrally and has an illumination optical system (13) projecting an illumination beam toward photographing objective eyes (E) along an illumination optical axis (O2) intersected at a predetermined angle with a photographing optical axis (O1).Type: GrantFiled: August 13, 2003Date of Patent: December 16, 2008Assignee: Kabushiki Kaisha TOPCONInventors: Naoyuki Maeda, Yoko Hirohara, Toshifumi Mihashi
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Patent number: 7441900Abstract: A contrast chart device of the present invention comprises a contrast target presenting part for presenting a contrast target for a contrast sensitivity test at prescribed timing; a pupil data measuring part for producing an image of an anterior ocular segment of a subject and measuring the diameter or area of a pupil region in the anterior ocular segment; and a measurement timing forming part for forming timing at which the pupil data measuring part performs measurement.Type: GrantFiled: February 7, 2002Date of Patent: October 28, 2008Assignee: Topcon CorporationInventors: Toshifumi Mihashi, Yoko Hirohara
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Publication number: 20080246921Abstract: To provide an eye examination apparatus and an eye examination method that make it possible to measure eyesight or contrast sensitivity in the binocular viewing state and further make it possible to measure optical characteristics in such an appropriate binocular viewing state.Type: ApplicationFiled: March 27, 2008Publication date: October 9, 2008Inventors: Toshifumi MIHASHI, Yoko HIROHARA, Mariko KOBAYASHI
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Publication number: 20080231806Abstract: An ophthalmic apparatus comprises a projection system in which a pattern member is provided with a predetermined pattern for measuring the shape of the cornea of an eye of a subject, the predetermined pattern is thereby projected on the cornea of the eye of the subject, and an optical observation system in which light flux having a shape of the predetermined pattern emitted from the projection system is reflected at the cornea of the eye of the subject, the eye of the subject is observed by the light reflected by the cornea. A surface at the eye of the subject side of the pattern member is coated with a paint having a filtering property that transmits infrared light and blocks visible light.Type: ApplicationFiled: March 20, 2008Publication date: September 25, 2008Inventors: Naoki Nakazawa, Koji Nakajima, Toshifumi Mihashi
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Publication number: 20080123053Abstract: Scattering can be measured by using an optical system having a Hartman-Shack wave-surface sensor.Type: ApplicationFiled: November 15, 2007Publication date: May 29, 2008Inventors: Toshifumi Mihashi, Yoko Hirohara, Takashi Fujikado, Naoyuki Maeda