Abstract: A laser surveying equipment includes a laser beam luminous section, a suspending reflection member suspended in such a manner as to reflect laser beam radiated from the laser beam luminous section upward and always to direct the optical axis of such reflected light in the perpendicular direction, and a projection lens system adapted to project the laser beam after forming it into a generally parallel flux of light. A rotary reflection member can be rotatably arranged in order to displace by approximately 90 degree an optical path of parallel flux of light obtained from the projection lens system and to scan the parallel flux of light toward a surveying object within a horizontal plane.

Abstract: An ophthalmologic photographing apparatus is disclosed. It comprises an observation light source for illuminating an eye to be tested; an observation optical system for forming an observation image of the eye to be tested and a corresponding image optically conjugate to the former; a photograph light source; a photograph device for photographing the eye to be tested; a light measuring device formed of a number of light receiving elements for dividing the corresponding image into a number of picture elements in order to measure the light volume per each picture element. The light receiving elements being disposed at a position where the corresponding image is formed. An indicator formed of a number of indicating elements corresponding to the light receiving elements and disposed at a position where the observation image is formed or otherwise at a position conjugate thereto.

Abstract: A gas stream blower for non-contact type tonometer comprises a cylinder, a piston arranged in the cylinder to divide the interior thereof into an air open chamber and a compression chamber, a nozzle communicated with the compression chamber such that air in compression chamber is compressed by advancing the piston toward the compression chamber and thus the compressed air is blown toward an eye-examining position through the nozzle, a first one way valve which is fitted in the piston and is closed at the time of air compressing, and a second one way valve which is provided in the midway of a communicating path between the compression chamber and the nozzle and is opened when the pressure of the compressed air is higher than a predetermined value.

Abstract: An eye refractometer is disclosed. It comprises a projection optical system including a light source portion and an objective lens disposed opposite to an eye under test, and a ring-shaped diaphragm or perforated mirror for forming a ring-shaped image pattern of the pupil of the eye and on the retina, a bundle of rays from the light source are projected to the eye under test through the objective lens and the diaphragm to form a ring-shaped pattern image at the retina of the eye under test through the peripheral area of a pupil surface of the eye under test; a light receiving optical system for receiving light reflected from the retina in a ring-shaped pattern image on a photo-electric detector through the central portion of the pupil; and a microprocessor for measuring the size and the configuration of the ring-shpaed pattern image from signals emitted from the photo-electric detector, and determining the refractivity of the eye under test therefrom.

Abstract: A holographic interferometer comprising a source of laser beams, a condenser lens for converging a laser beam supplied from said laser-beam source, a pinhole which allows the passage of said converged laser beam, a collimator lens having a focal point which lies on said pinhole, a beam splitter disposed in an inclined manner between said pinhole and said collimator lens, a spacial filter disposed on the optical axis of a light reflected from said beam splitter and at an optically conjugate position relative to said pinhole, and a hologram standard disposed between said spacial filter and said beam splitter.

Abstract: An eye fundus camera for taking photographs of a patient's eye fundus. The camera includes a pair of viewing targets located at the opposite sides of the optical axis. A switch is provided for alternately energizing the targets so that an appropriate one of the targets emits light beams when the camera housing is placed to take photographs of one of the patient's eyes.

Abstract: The present invention relates to an optical reader for scanning a surface to be scanned by using information beam ray such as laser beam ray and optically reading a recorded information such as bar code recorded in the surface to be scanned. The optical reader is constituted such that optical beam emitted from a light source is reflected on a first rotary multiface mirror to scan on a surface to be scanned, and information beam reflected on the surface to be scanned is reflected on a second rotary multiface mirror to guide to an opto-electric transforming means. A scanning optical path for permitting the optical beam from the light source to pass therealong is formed independently from a reflecting optical path for permitting the information beam from the surface to be scanned to pass therealong.

Abstract: An improved eye refractive power measuring apparatus is disclosed. The apparatus includes a measurement system for projecting a measurement target image to the retina of an eye to be tested and measuring the refractivity of the eye to be tested by detecting the focussing state of the measuring target image. In addition, it has an eye position detection system for detecting a shifted amount from a proper position of the eye to be tested and an arrangement for correcting a measurement result of the eye refractivity based on such detected result.

Abstract: A subjective ophthalmic instrument has optotypes which are observed by the patient through a correcting lens system of adjustable refractive power. The subjective ophthalmic instrument further has a optotype examination system which includes an imaging optical system for producing an image of a patient's fundus projected with an image of the optotypes at a camera tube, and display means for displaying the optotype image in accordance with the output of the camera tube.

Abstract: A photometer is providing including light detecting means for detecting incident light and generating electric signals in response thereto as a measure of the incident light thereon, and optical means for guiding light to the light detecting means from a standard light source in a calibration mode and from an object, a photometric quantity of which is to be measured, in a measurement mode.

Abstract: Lens meter and method of measurement of progressive multifocal lens using the same which is able to set the amount of movement of the lens and to simply position a far- or near-distance refraction characteristics-measuring portion of a progressive multifocal lens. In accordance with the method the optical center of a lens is first found from measurement employing the lens and using the optical center as point of origin, the lens is moved by a distance up to the far-distance refraction characteristics measuring portion and the near-distance refraction characteristics measuring portion of the lens mentioned by the lens manufacturer, so as to effect alignment with the measurement optical axis of the lens meter, thereby measuring the refraction characteristics of each measuring portion.

Abstract: An ocular position measuring apparatus comprising a pair of fixation marks capable of emitting visible flickering beams for being watched by patient, a first pair of half mirrors positioned between the patient's eyes and the marks and an observing system for observing images of the patient's eyes on produced by light beams reflected by the half mirrors.

Abstract: Ophthalmoscopic instrument having working position detector. An object lens has an optical axis and is adapted to be positioned to confront a patient's eye at a working distance. The patient's cornea has a center of curvature. An observing optical system focuses a light beam reflected from the eye and passing through an objective lens on an image plane. A detecting system detects that the eye is properly positioned with respect to the objective lens. The detecting system includes at least two apertures allowing light beams from a single target mark to pass therethrough. A target mark projection system projects the beams passed through the respective apertures in directions crossing each other on the optical axis of the objective lens so that a target mark image is formed at the center of curvature of the cornea when the eye is properly positioned with respect to the objective lens.

Abstract: A slit lamp comprising a slit light projection optical system having a slit aperture for projecting a slit pattern light along a slit plane to a crystalline lens of a patient's eye and a microscope for observing a section of the crystalline lens which is illuminated by the slit pattern light. The microscope comprises an crystalline lens section recording optical system including a recording device having an image plane for recording the section of the crystalline lens of the patient's eye illuminated by the slit pattern light, and a retroillumination image recording optical system for guiding a retroillumination image of the crystalline lens to the recording device of the crystalline lens section recording optical system for recording the section of the crystalline lens.

Abstract: An eye disease inspection instrument comprising a slit light projection optical system for projecting a slit light along a projecting optical axis to a patient's eye, a first optical system for observing a crystalline lens of the patient's eye at a section which is being illuminated by the slit light, a second optical system including an objective lens having an objective optical axis substantially coaxial with respect to the projecting optical axis for performing an observation under a retroillumination method.

Abstract: A photometrical apparatus has a first light receiving element, and a second light receiving element less sensitive to temperature and other environmental influences than said first light receiving element whereby a value Pm of measured quantity of light from the subject is calculated from the following formula ##EQU1## Pr designates a quantity of light from a standard light source, Dr and Dm designate outputs of the first light receiving element generated by the light from the standard light source and the subject, Dpo and Dpt designate outputs of the first light receiving element generated by the light from the reference light source and the subject, and Dso and Dst designate outputs of the second light receiving element generated by the light from the reference light source and the subject.

Abstract: There is disclosed a non-contact type tonometer for measuring intraocular pressure of an eye under test in which a fluid for deforming a cornea, discharged along an optical axis of an alignment optical system toward the cornea in order to deform the cornea. The intraocular pressure is measured based on the measured deformation of the cornea. The alignment optical system comprises a projection optical system which is independently adapted for projecting a pair of target rays for alignment verification toward the cornea; and an alignment verification optical system in which corneal specular reflection rays of the pair of target rays are guided to the objective lens as if the pair of target rays were radiated from the corneal focal point. When an optical axis of the projection optical system is made coincident with the focal point of the cornea and the reflected target images are formed by the objective lens, alignment verification is effected based on duplication of the pair of target images.

Abstract: A stereo-microscope is disclosed. It comprises a common objective lens system, a first and second imaging lens systems having optical paths parallel to that of the objective lens system producing intermediate images of an object, a first and second optical path deflecting devices arranged behind the respective imaging lens systems for deflecting the respective ejection bundle of rays outwardly relative to the optical path of the objective lens system, and a first and second ocular systems arranged behind the respective optical path deflecting device for observing the respective intermediate images. It is characterized in that a stereo angle .omega. which is to be decided depending on the base length between the first and second imaging lens systems and an observation angle .theta. which is defined between the observation optical paths of the first and second ocular systems are arranged to be equal. Another stereo-microscope is also disclosed.

Abstract: An automatic perimeter automatically presenting stimuli in a plurality of conditions, in which the presentation of stimuli can be readily stopped by an operator during the presentation, and an accurate examination of eyesight is carried out in accordance with eliminating the few latest perception signals before the stimulus presentation is stopped during an examination of eyesight.