Kabushiki Kaisha Topcon

Other

Tokyo Kogaku Kikai Kabushiki Kaisha

Tokimec Inc.

Eiichi Sano

Akio Ichikawa

Fumio Akikuni

Hiroshi Minegishi

Kazuo Nunokawa

Yoshihiko Hanamura

Toru Suzuki

Masahito Asa

Hideaki Tokoro

Masayuki Nakajima

A position sensor for movable body, which detects a position of a movable body which moves in a reciprocal direction, comprises; at least two portions to be detected, which are provided on one side surface of the movable body with respect to a moving direction of the movable body, and at least two detectors for detecting the portions to be detected, wherein one portion to be detected is not arranged on a line parallel to the moving direction, on which the other portion is disposed, nor arranged on a line perpendicular to the moving direction, on which the other portion is disposed, one detector corresponding to the one portion is arranged so that when the one detector detects the one portion by moving the movable body in one direction, the other portion is moved in the one direction beyond the one detector, and the other detector corresponding to the other portion is arranged so that when the other detector detects the other portion by moving the movable body in the other direction, the one portion is moved in the other direction beyond the other detector.

Position sensor for movable body and optical interferometer

An optical part driving device for moving an optical part, comprises; a driving timing pulley, a pair of driven timing pulleys, a timing belt wound by the driving timing pulley and the driven timing pulleys and connected with the optical part between the pair of driven timing pulleys, and a pair of tension pulleys for tensing the timing belt on both sides of the driving timing pulley.

Optical part driving device incorporated into a detachable block and optical interferometer including same

An optical interferometer in which a reference light and a light to be measured interfere with each other includes a casing, a movable optical part which is movable with respect to the casing, a fixed optical part which is fixed to the casing, and an attachment emember for attaching the movable optical part to the casing and for removing the movable optical part form the casing.

Optical interferometer with a casing and an optical part that is movable with respect to the casing

A fundus camera, for taking photographs by fluorescence, has an illuminating optical system to illuminate a fundus. The illuminating optical system is provided with a diaphragm that can be adjusted to modify the illumination state of the fundus according to the light reflected from the fundus when taking photographs by fluorescence. As a result, a good photographic image of the fundus can always be obtained.

Fundus camera

This invention concerns a fundus camera which can take photographs other than by fluorescence or by fluorescence. An optical device is withdrawn from the optical path of a photographic system at the same time as a barrier filter for taking photographs by fluorescence is inserted and is inserted in the optical path of the photographic system for observation purposes at the same time as the barrier filter is removed. The optical device has the same optical path length as the barrier filter, and thus a focused fundus image attained during observation is not upset when fluorescent photographs are taken.

The ophthalmic photographic apparatus of the invention comprises a means of detecting abnormalities in the filters used when a fluorescent agent is caused to fluoresce by infra-red light in order to photograph a subject's eye. According to the ophthalmic photographic apparatus of the invention, the abnormality-detecting means detects an abnormality if there is a flaw or deterioration of a filter used to take a photograph when a fluorescent agent is caused to fluoresce by infra-red light. The abnormality-detecting means preferably detects abnormalities of an exciter filter which transmits infra-red light in a specific wavelength range which causes fluorescence of a fluorescent agent in an illuminating optical system having an illuminating light source. More specifically, this abnormality-detecting means comprises a reflecting mirror, disposed on the opposite side of the exciter filter to the illuminating light source, which reflects a part of the illuminating light (here, the term illuminating light will be understood to mean infra-red light in the specific wavelength range and illuminating light in other wavelength ranges) that has passed through the exciter filter; a photodetector disposed in the direction of reflection of the reflecting mirror which detects illuminating light reflected by the mirror; and a discriminating circuit which determines whether or not there is an abnormality in the exciter filter according to the output variation of the photodetector.

Ophthalmic photographic apparatus using a fluorescent agent

A fundus camera having an illuminating optical system is provided with illuminating diaphragms for non-fluorescent photography and fluorescent photography. The illuminating diaphragm for non-fluorescent photography and the illuminating diaphragms for fluorescent photography respectively have light transmitting regions of different surface areas.

A waveguide having a pair of quarter-wavelength impedance transformers and adapted to divide and combine microwaves. The pair of quarter-wavelength impedance transformers includes two strip transmission lines connected together at one end, two ground conductors each located adjacent to and spaced from a respective one of said strip transmission lines, each said ground conductor serving as a ground potential at least mutually to the adjacent strip transmission line, and a dielectric substrate supporting thereon said strip transmission lines and said ground conductors. The two strip transmission lines may be connected to each other at numerous positions by resistors.

Waveguide for dividing and combining microwaves

This invention discloses a fundus camera which can take fluorescent photographs by infra-red light and other types of photographs. It comprises detecting means for detecting whether or not the photograph being taken is a fluorescent photograph by infra-red light, means for automatically setting the amount of light emitted by a photographic source when the photograph being taken is not a fluorescent photograph by infra-red light, and changing over to manual setting of the amount of light emitted by said photographic source when the photograph being taken is a fluorescent photograph by infra-red light, according to information provided by said detecting means.

An ophthalmological photographing instrument has photographing means for imaging the fundus of an eye to be tested every time a photographing switch is actuated, and a barrier filter to be inserted into a photographing optical path when a fluorescence photography is performed. It also has a light receiving sensor for receiving fluorescence emitted from the eye fundus and control means for inserting the barrier filter into the taking optical path every time the taking switch is actuated when a light receiving signal output from the eye fundus becomes either larger or smaller than a predetermined value.

Opthalmological photographing instrument

An eye fundus camera adapted to be mounted with a first (12) and a second (20; 26, 27) apparatus for observing and/or photographing the eye fundus, and including a movable mirror (18) moved between a first position where it admits light from the eye fundus to the first apparatus (12) and a second position where it deflects the light toward the second apparatus (20; 26, 27), whereby various modes of operation can be carried out.

Eye fundus camera

An ophthalmic instrument such as an eye fundus camera including an illuminating system which projects an illuminating light through a ring-shaped aperture to a patient's eye. There is provided a working distance detecting device which includes a light receiving section provided around the objective lens. A portion of the illuminating light as reflected at the cornea of the patient's eye is received by the light receiving section to determine a correct working distance.

Ophthalmic instrument having working distance detecting means

A working position locating device for an ophthalmologic apparatus in which the projected image of a ring slit aperture is offset from the projecting optical axis when the position of the apparatus is being changed so that the ring slit image be seen on the focal plane of the observation optical system, whereby the proper working position of the objective lens relative to the eye can be grasped from the position of the ring slit image.

Growing community of inventors

Tokyo, Japan

Eiichi Sano