Abstract: A non-contact tonometer includes plural sensor elements as a cornea deformation detecting system in a plane substantially conjugate with an illuminating light source through corneal reflection when the cornea of an eye to be examined is deformed by a predetermined amount, whereby measurement of the eye pressure is made possible even if the alignment of the apparatus relative to the eye to be examined is inaccurate.

Abstract: A laser applying apparatus provided with a light reflective coupling member having a reflecting coupling member having a reflecting film for reflecting a laser light for medical treatment and transmitting a guide light therethrough provided on the side of a portion to be examined and having a reflecting film for reflecting the transmitted guide light partly provided behind the first-mentioned reflecting film.

Abstract: A non-contact eye pressure meter is provided with a cornea deforming system for blowing a compressed fluid of a pressure variable with time against the cornea of an eye to be examined from a nozzle provided in a predetermined optical member opposed to the eye to be examined, and a deformation detecting system for applying a light beam from a predetermined light source to the eye to be examined past only one area of the interior of the nozzle and the interior of the predetermined optical member which is in the outer peripheral portion of the nozzle and receiving the cornea-reflected light by a predetermined light-receiving element past only the other area. The light source and the light-receiving element are set optically substantially conjugately through corneal reflection when the cornea of the eye to be examined is deformed to a predetermined curvature.

Abstract: A lens meter has a single point-like light source, a collimator lens for collimating the light from the point-like light source and causes it to enter a lens to be examined, a plural-aperature stop disposed immediately reawardly of the lens to be examined and having three or more apertures, a light-receiving optical system including a prism assembly for separating the light beams from the plural-aperture stop on the light-receiving surface thereof, and an array light-receiving element disposed at the focus position of the light-receiving optical system for measuring the refractive value of the lens to be examined by the mutual positional relation between the received light beams.

Abstract: An apparatus for measuring the refractive power of an eye has a target projecting system for projecting a target light beam onto the fundus of an eye to be examined through a predetermined region of the pupil of the eye to be examined, and a light-receiving optical system for receiving a light beam reflected by the eye fundus in at least three meridian directions through a region of the pupil of the eye to be examined different from the predetermined region. The light-receiving optical system includes a plurality of image rotating prisms for converting into a predetermined direction the direction of displacement to each meridian direction of the light beam reflected by the eye fundus produced by the difference in the refractive power of the eye to be examined. A light detecting device has a direction of light detection coincident with the predetermined direction and detects the light-position of the light beam reflected by the eye fundus which depends on the refractive power of the eye to be examined.

Abstract: A medical television system includes a television camera and a selector. The television camera includes a filter for separating visible light into three wavelength regions and transmitting near-infrared rays, and an image pickup element having sensitivity to both visible light and near-infrared rays. The selector selectively supplies the visible light separated into the three wavelength components or the near-infrared rays to the television camera.

Abstract: A stereoscopic microscope has an objective opposed to an object to be examined, having its optic axis in a horizontal plane and projecting a parallel light beam, a pair of imaging optical systems for right and left eyes disposed rearwardly of the objective, a pair of optical devices having an even number of reflecting surfaces inclining the optic axes of the imaging optical systems so as to provide a predetermined angle of depression and a predetermined convergence angle, an erector rotatable about the optic axes inclined by the optical devices for the adjustment of the eye width, and a pair of eyepieces for enlarging and observing the image of the object to be examined therethrough.

Abstract: An automatic optometer provided with a first visual target for measuring the visual power of a subject, a response input unit for the subject to input a response corresponding to the visual target, a control unit for determining the accuracy of the subject's response input and for presenting additional different visual targets, a counter, the counter being reset each time a visual target is presented, a comparison unit for comparing the output of the counter with a predetermined value, and request means for requesting the subject's response input in accordance with the output of the comparison unit.

Abstract: A stereoscopic microscope is provided with a single objective lens and a pair of eyepieces disposed rearwardly of the objective lens. A pair of interpupillary distance adjusting means and a pair of refraction type vergence adjusting means are disposed between the objective lens and the eyepieces.

Abstract: At least three light beams are applied to different positions on an optical element to be measured. The light beams coming via the optical element to be measured are received through a light-receiving lens by a two-dimensional light position detecting system provided at the rearward focus position of the light-receiving lens or at a position conjugate therewith or are received by two-dimensionally disposed light position detecting system. Three deviation vectors are detected and the refractive powers in three meridian directions are detected, or at least five light beams are applied to different positions on an optical element to be measured and from five deviated beam positions, a general elliptical curve coupling them is specified, whereby the degree of astigmatism, the direction of astigmatism and the refractive power are calculated.

Abstract: An apparatus for detecting abnormality in a spinal column is provided with means for projecting at least a slit-like light which is parallel to the imaginary spinal line on each of right and left sides of the back of an inspected person, pickup means for taking the image of the left and right backs of the inspected person, and a signal processing unit for detecting and comparing the positions of the slit-like lights on the right and left shoulders by means of the scanning lines of the pickup means.

Abstract: The focusing system of the present invention includes an objective lens facing an eye to be examined, an aperture mirror for reflecting the illuminating light, an aperture stop, a photographing lens, a photosensitive lens and a focusing lens provided between said aperture stop and the photographing lens.The system further comprises a system for directing the beam reflected at the reflecting spot located at the image side of the objective lens or by the aperture mirror or a dichroic mirror located at the image side of the aperture mirror toward the eye ground, and a light-receiving optical system for focusing the beam reflected from the eye ground onto a photosensor through the objective lens, wherein the focusing lens is driven by the output of said photosensor.

Abstract: An eye-refractometer includes an objective optic having a first optical path, an apertured mirror for dividing the first optical path into a second optical path and a third optical path, a mask disposed in the second optical path and having linear marks orientated in at least three directions, a radiation source for illuminating the mask, a mask disposed in the third optical path and having liner detecting areas orientated in at least three directions and photocells arranged behind the respective areas. Improvements in this eye-refractometer comprise an apertured plate disposed between the apertured mirror and one of above said masks and an annular apertured plate disposed between said apertured mirror and the other mask. Another improvement is found in that the length of the linear detecting area is shorter than the length of optimum focused images of the linear marks.

Abstract: An eye-fundus examining instrument is provided with a phototaking system, an illumination system for illuminating the fundus of an eye, a projecting system for projecting a focus mark and a comparison mark, a finder coupled to the phototaking system for observing therethrough the fundus of the eye, the focus mark and the comparison mark, a linear photosensor array for detecting the focus mark image reflected by the fundus of the eye, a light-receiving system focused to the fundus of the eye simultaneously with the phototaking system and the projecting system, a focusing mechanism for focusing the phototaking system to the fundus of the eye, a manual adjust member for manually driving the focusing mechanism, a servomotor for driving the focusing mechanism, a control circuit for controlling the servomotor by the output of the linear photosensor array, and a switch for selecting the power supply to the control circuit.

Abstract: In an apparatus having a ray generator for directing measuring rays through a first optical path, a light-receiving portion for receiving the measuring rays reflected by the eye fundus through a second optical path, and a uniting device for uniting the first and second optical paths to form a third optical path, and also having movable lens groups in each of the first and second optical paths or a movable lens group in the third optical path, and wherein the movable lens groups or group is moved along the optical path to measure the refractive power of the eye from signals corresponding to the positions of the movable lens groups or group and the signal of the light-receiving portion, the movable lens groups or group is made into an afocal system to prevent the dimensions of the pupil from being varied and a collimator for collimating the principal rays is fixedly disposed on that side of the movable lens groups or group which is adjacent to the eye to be examined.

Abstract: An automatic eye-refractometer includes a projector for projecting a test pattern onto the fundus of an eye to be examined, a photo-electric device disposed to receive an image of the test pattern reflected upon the fundus of the eye, a calculator for calculating the refractive power of the eye using outputs from the photo-electric device and a processor for processing the results of the calculation into digital video signals. The eye-refractometer is further provided with a video camera for image picking up the front part of the eye through an objective lens of the projector to produce video signals and a video display device for displaying on a screen a picture produced from the video signals. With the measuring apparatus, the examiner can observe the image of the front part of the eye to be examined and can properly arrange the eye and the objective lens to each other while watching the picture displayed on the screen.

Abstract: An eye refractometer is provided with a projection optical system for projecting test beams forming test patterns such that the central ray of each test beam passes through the pupil of the eye to be inspected while being spaced apart from the optic axis in order to form test patterns corresponding to three meridians forming 60.degree. with each, a focusing lens disposed in the projection optical system and movable only in one direction during one measurement, and a beam detecting device for detecting the reflected images of the test patterns by the retina of the eye and generating electrical signals corresponding to the three meridians.

Abstract: An ophthalmoscopic instrument having an infrared image converter tube for observation and/or examination of an ocular fundus prior to recording an image thereof provided with a range finding device which assists in establishing a suitable working distance between an eye and an objective lens in the instrument optically aligned to each other. A light beam is projected onto the iris of an eye to be examined or the cornea thereof near or at the center and is transmitted by scattering reflection or regular reflection respectively from the iris or cornea to a photo-detecting system which produces an electrical output signal capable of reaching a peak value only when the transmitted light enters a slit ahead of a light sensitive surface or strikes that one of light sensitive segments which is adapted to be the most light responsive, as the device is moved in unison with the instrument body.

Abstract: An ophthalmoscopical apparatus for carrying out aligning and/or spacing an eye examining instrument is disclosed. The apparatus includes a projection optical system disposed obliquely to the optical axis of the objective lens of the instrument. A beam of infrared light is projected from the projection optical system so as to form an image of indication at a position spaced from the objective lens by a predetermined distance. A beam reflected upon the anterior part of the subject eye is incident on the objective lens and focused on the light receiving surface of an image pick-up tube through an image transmitting system. Thus, an image of the reflected beam is displayed on a screen of cathode ray tube. The examiner adjusts the position of the instrument while observing the image on the cathode ray tube. The adjustment is made in the directions of up-and-down, left-and-right and for-and-back until the image of reflection on the cathode ray tube comes in a predetermined position.

Abstract: An eye fundus camera permitting simple focusing is disclosed. An optical system with a microprism projects an image of a focusing mark on the eye fundus.When the mark image formed on the eye fundus is not just focused, this mark image is divided and separated into at least three directions. An objective lens forms the image which is formed on the eye fundus on a recording film and cooperates with the projection lens of the mark projection optics. Therefore, the objective lens can be focused by observing the mark image which is formed on the eye fundus.