Abstract: A noncontact laser microsurgical apparatus and method for marking a cornea of a patient's or donor's eye in transplanting surgery or keratoplasty, and in incising or excising the corneal tissue in keratotomy, and for tissue welding and for thermokeratoplasty. The noncontact laser microsurgical apparatus comprises a laser source and a projection optical system for converting laser beams emitted from the laser source into coaxially distributed beam spots on the cornea. The apparatus further includes a multiple-facet prismatic axicon lens system movably mounted for varying the distribution of the beam spots on the cornea. In a further embodiment of the method of the present invention, an adjustable mask pattern is inserted in the optical path of the laser source to selectively block certain portions of the laser beams to thereby impinge only selected areas of the cornea.

Abstract: A noncontact laser microsurgical apparatus and method for marking a cornea of a patient's or donor's eye in transplanting surgery or keratoplasty, and in incising or excising the corneal tissue in keratotomy, and for tissue welding during thermokeratoplasty. The noncontact laser microsurgical apparatus comprises a laser source and a projection optical system for converting laser beams emitted from the laser source into coaxially distributed beam spots on the cornea. The apparatus further includes a multiple-facet prismatic axicon lens system movably mounted for varying the distribution of the beam spots on the cornea. In a further embodiment of the method of the present invention, an adjustable mask pattern is inserted in the optical path of the laser source to selectively block certain portions of the laser beams to thereby impinge only selected areas of the cornea.

Abstract: A noncontact laser microsurgical apparatus and method for marking a cornea of a patient's or donor's eye in transplanting surgery or keratoplasty, and in incising or excising the corneal tissue in keratotomy, and for tissue welding and for thermokeratoplasty. The noncontact laser microsurgical apparatus comprises a laser source and a projection optical system for converting laser beams emitted from the laser source into coaxially distributed beam spots on the cornea. The apparatus further includes a multiple-facet prismatic axicon lens system movably mounted for varying the distribution of the beam spots on the cornea. In a further embodiment of the method of the present invention, an adjustable mask pattern is inserted in the optical path of the laser source to selectively block certain portions of the laser beams to thereby impinge only selected areas of the cornea.

Abstract: An apparatus for imaging and displaying a blood stream state of an eye to be tested. A laser beam is first irradiated onto an eye to be tested. And light reflected from an irradiated area on the eye is detected and information about the reflected light is stored. And second, the bloodstream state of the eye are calculated on the basis of the information, the imaged results are displayed on a display means of the apparatus. At the same time, a pulse wave of a person to be tested is detected by a pulse wave detecting means, the wave shaped of the pulse wave is displayed by a display controlling means, which controls to display the measuring time and portion of the bloodstream state compositely on the present wave shape.

Abstract: An ophthalmic measuring device is used for measuring blood flow at a fundus to be subjected to ophthalmic examination. The device includes and illumination system for illuminating the fundus to be examined, a projection system for irradiating a predetermined area of the fundus with a measuring laser beam, a detection device for detecting a reflected measuring laser beam reflected from the irradiated area, a storage device for storing signals obtained by the detection device, and an arithmetic processing section for arithmetically processing blood flow in a blood vessel of the fundus based on the stored signals. The device has the capability of indicating an area to be detected on the fundus. The device allows a photograph of the fundus to be taken, superimposed on an image of the indicated area, substantially simultaneously with the storage of the signals in the storage device.

Abstract: A noncontact laser microsurgical apparatus and method for marking a cornea of a patient's or donor's eye in transplanting surgery or keratoplasty, and in incising or excising the corneal tissue in keratotomy, and for tissue welding and for thermokeratoplasty. The noncontact laser microsurgical apparatus comprises a laser source and a projection optical system for converting laser beams emitted from the laser source into coaxially distributed beam spots on the cornea. The apparatus further includes a multiple-facet prismatic axicon lens system movably mounted for varying the distribution of the beam spots on the cornea. In a further embodiment of the method of the present invention, an adjustable mask pattern is inserted in the optical path of the laser source to selectively block certain portions of the laser beams to thereby impinge only selected areas of the cornea.

Abstract: An interferometer for measuring an aspherical shape uses a computer generated hologram. The interferometer comprises a hologram disposed at each of positions conjugate with plural types of aspherical surfaces to be examined and filed lens means disposed between a position conjugate with a convex aspherical surfaces and another position with a concave aspherical surface. The interferometer can measure plural types of aspherical surfaces to be examined without need of changing the position of the interferometer for each of the aspherical surfaces to be examined, even if the number of different surfaces to be examined increases.

Abstract: A light wave range finder has a range finding optical system in which the intensity of a coherent beam of light emitted from a coherent light source is modulated and delivered to an object and a reflecting beam of light reflected on the object is received by an light receiving element. A distance to the object is measured based on a phase detection of the reflecting beam of light.

Abstract: A range finder for finding a distance to an object comprising an outgoing light guiding wave path, a reference light guiding wave path, and an incoming light guiding wave path. The finder further comprises wavelength changing means for changing the wavelength of the beam of light emitted from the light source, wavelength detecting means for detecting the wavelength of the beam of light emitted from the light source, and calculating means for detecting at least two peaks of the signal coming from the light receiving element when the wavelength of the light source is changed by the wavelength changing means, finding the wavelengths of the light source, respectively, from the wavelength detecting means at the time when the signal exhibits the two peaks, and calculating the distance to the object according to an operation expression memorized beforehand with reference to such obtained two wavelengths.

Abstract: A laser beam scanning type ophthalmological instrument has a first laser beam light source for emitting a first laser beam; a second laser beam light source for emitting a second laser beam of a different wavelength from that of the first laser beam; and a light receiving element for receiving a laser beam reflected by an eye fundus, and in which the eye fundus is scanned by the first and second laser beams in order to observe the eye fundus or in order that a view field, etc. can be inspected. The laser beam scanning type ophthalmological instrument is characterized in that the first and second laser beams emitted by the first and second laser beam light sources can independently be adjusted in light quantity.

Abstract: An integrated-photocircuit interferometer (20) comprises a substrate (21) in which coherent light for measurement emitted from a light source (23) is directed through an exit waveguide (22) toward a corner cube prism (34) which can be movable with an object to be measured. The light reflected back from the prism (34) can enter an inlet waveguide (33) having branch waveguides (35, 36) which split the incident measurement light. Part of the light transmitted through the exit waveguide (22) is transferred to reference waveguides (26, 27) which provide different optical path lengths for the light propagated therethrough. The "reference beams of light" which has been transmitted through the different lengths of optical paths provided by the reference waveguides (26, 27) are introduced into the branch waveguides (35, 36) where interference occurs between the reference beams and the split beams of incident light from the corner cube prism (34).

Abstract: A light interferometer has an interferometer portion for interfering a measuring light and a reference light, and a light signal processing portion for processing a signal according to an interference signal which changes according to the change of an optical path length of the measuring light. The interferometer portion has a first light source for generating a coherent light, a light interference portion for dividing the coherent light emitted by the first light source into a reference light and a measuring light in order to introduce the measuring light to an object, making the measuring light reflected by the object and the reference light interfered with each other and introducing thereof to a photo detector, and an optical path length periodically changing means for periodically changing the difference of an optical path length of the reference light with respect to the optical path length of the measuring light relatively at a constant amplitude.

Abstract: A laser beam scanning type eye fundus camera has a laser beam generator for generating a laser beam; an illuminating system for illuminating the fundus of an eye to be tested by scanning the laser beam generated by the laser beam generator on the eye fundus; a first and a second light receiving portions for receiving a reflecting light of the laser beam reflected by the eye fundus; a first light receiving system for guiding the reflecting light of the laser beam reflected by the eye fundus to the first light receiving portion; a second light receiving system for guiding a fluorescence excited at the eye fundus by the laser beam; and an electronic circuit for forming an eye fundus image on a monitor TV according to an output signal coming from the first and second light receiving portions.

Abstract: A method of analyzing interference fringes for use in a holographic interferometry process for measuring, by using a computer generated hologram, the shape of an object to be examined. The method comprises:a first step of obtaining a wave surface (xl, yl, zl) of a surface to be measured from measurement interference fringes;a second step of obtaining a coefficient A.sub.k relative to the wave surface (xl, yl, zl) of the surface, from a coefficient a.sub.ij of a series of the object wave which has been obtained based on the hypothesized coordinates on a computer hologram at the time when the computer generated hologram is made, and from a coefficient b.sub.ij of a series of the object based on the hypothesized coordinates on the object, the coefficient A.sub.k minimizing the square sum or the maximum value of a function of Xl, Yl, Zl, and a third step of obtaining a shape error from the ideal shape of the object by calculating the function on the basis of the A.sub.k.

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: 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: Inclination measuring instrument having a tube having a concave inside surface and filled with liquid so as to have a bubble, a first electrode provided on the outside surface of the tube opposite to the bubble, second and third electrodes provided on the outside surface of the tube opposite to the first electrode and located along the direction of shift of the bubble, a guard electrode provided on the outside surface of the tube to frame the first, second and third electrodes and to be supplied with a predetermined voltage, and processing means for connecting a first capacitor consisting of the first and second electrodes and second capacitor consisting of the first and third electrodes so as to calculate the inclination of the tube from the output of the first and second capacitors.

Abstract: A level detector comprising a container holding two fluids. Four capacitors are formed between four electrodes disposed on one side of the container cooperating with an opposing common electrode. Two of the capacitors have a capacitance value influenced by the position of one of the fluids in the container (related to container tilt) but in inverse relationships. A third capacitor is influenced by the dielectric value of the two fluids but in a manner independent of the tilt angle of the container. The fourth capacitor has a capacitance value influenced only by the dielectric constant of one of the two fluids. Based on the four capacitance values, circuitry is provided for generating a signal relating to the angle of the container.

Abstract: A displacement measuring device, using an incremental code, which includes a coding member (22) resting on the object (21) to be measured and having a coding section for generating such signals that a sensing element can discriminate the signals as 0 or 1, sensing means (25A, 25B) disposed to sense the coding section of the coding member for producing sensed signals in response to the displacement of the coding member (22), and rectangular wave-converting circuits (27A, 27B) for receiving and converting the sensed signal into rectangular wave signals. A clock pulse generator (28) is provided in the device for generating a clock pulse with a higher repetition-frequency than the repetition-frequency of the sensed signal.

Abstract: A displacement measuring device, using an incremental code, which includes a coding member (22) resting on the object (21) to be measured and having a coding section for generating such signals that a sensing element can discriminate the signals as 0 or 1, sensing means (25A, 25B) disposed to sense the coding section of the coding member for producing sensed signal in response to the displacement of the coding member (22), and rectangular wave-converting circuits (27A, 27B) for receiving and converting the sensed signal into rectangular wave signals. A clock pulse generator (28) is provided in the device for generating a clock pulse with a higher repetition-frequency than the repetition-frequency of the sensed signal.