Abstract: An infrared imaging lens (1) includes a plurality of lenses (L1 to L3) which are disposed in respective positions, the plurality of lenses each being made of glass having a refractive index of 2.8 to 4.0 measured at a wavelength of 10 ?m, the infrared imaging lens having an image circle having a diameter which is 0.7 times to 1.3 times a focal length of the infrared imaging lens.

Abstract: The present invention achieves an infrared imaging lens which is excellent in performance capability such as aberration despite its wide angle of view and which is adaptable to a far infrared region. An infrared imaging lens (1) includes: a first lens (L1) having negative refractive power; a second lens (L2) which is a meniscus that is convex to an image surface side; and an image surface side lens group (G) having positive refractive power, the first lens, the second lens, and the image surface side lens group being disposed in this order from an object side to the image surface side, the first lens and the second lens each being made of glass having a refractive index of not less than 2.8 measured at a wavelength of 10 ?m, and the infrared imaging lens having a half angle of view of not less than 60°.

Abstract: An apparatus for discriminating authenticity of a card 1 having a predetermined hologram corresponding to a kind of the card 1 to discriminate the authenticity of the card 1 based on the hologram, comprises: a measuring light projecting system (semiconductor laser 25a, collimating lens 25b) to project a measuring beam P onto the hologram; an area sensor 28 to receive reflected diffraction light of the measuring beam P reflected by the hologram; a plurality of discriminating calculation means 30˜32 to perform the authenticity discrimination for card 1 by achieving calculations corresponding to respective kind of the holograms based on output signals from the area sensor 28; and a selecting mean (selecting switch 24, switch circuit 29) to select any one of the plurality of discriminating calculation means 30˜32.

Abstract: An apparatus for discriminating authenticity of a card according to the present invention comprising measuring light projecting system 23 which projects a measuring beam of light P from a predetermined direction onto a hologram 2 formed on a predetermined position on a card 1, a light receiving element 24b which receives reflected diffraction light R1, R2 and R3 generated by the measuring beam of light P reflected on the hologram 2, an averaging means 25 which varies projecting position of the measuring beam of light P to average received light signals corresponding to distribution characteristics of light intensity on the light receiving element 24b, and a discriminating means 26 to discriminate authenticity for the card by a comparison of output from the averaging means 25 with an allowable value.

Abstract: A card authenticity judging apparatus includes a light projecting system for projecting a laser measurement light Q1 toward hologram which is provided on surface of a card 1 and on which an image 4′ based on a grating pattern 3 is formed, a Fourier transform lens 27 for forming grating pattern image on a light receiving section 28 on the basis of reflected diffraction luminous flux of being reflected from the hologram, and a judging means 30′ for judging authenticity of the card 1 based on photoelectric output from the light receiving section 28, in which authenticity of the card 1 is made to judge depending on grating pattern image based on reflected diffraction light.

Abstract: An simlified optical configuration is acheved and, a direction discrimination function and a high resolving detection function are performed by one light receiving section. A TE mode emitted from an optical waveguide section 3 transmits through a beam splitter 5 and is guided to a measurement optical path. A TM mode emitted from the optical waveguide is reflected by the beam splitter 5 and is guided to a reference optical path. First and second ¼ wave plates 10 and 11 are inserted in the respective optical paths, and the TE and TM modes are acted by a ½ wave plate while travelling forward and backward on the reference and measurement optical paths. A reference light (TM mode) is reflected by a reference reflection section 8 and transmits through the beam splitter section 5. A measurement light (TE mode) is reflected by a measurement reflection section 9 and is reflected by the beam splitter section 5.

Abstract: An simlified optical configuration is acheved and, a direction discrimination function and a high resolving detection function are performed by one light receiving section. A TE mode emitted from an optical waveguide section 3 transmits through a beam splitter 5 and is guided to a measurement optical path. A TM mode emitted from the optical waveguide is reflected by the beam splitter 5 and is guided to a reference optical path. First and second ¼ wave plates 10 and 11 are inserted in the respective optical paths, and the TE and TM modes are acted by a ½ wave plate while travelling forward and backward on the reference and measurement optical paths. A reference light (TM mode) is reflected by a reference reflection section 8 and transmits through the beam splitter section 5. A measurement light (TE mode) is reflected by a measurement reflection section 9 and is reflected by the beam splitter section 5.

Abstract: An optical system is fabricated in the form of one device, so that the simplified optical system is realized. A displacement is measured with a high resolving power utilizing an interference fringe. An interference measurement probe 2 receives a coherent light from a light source section 1, and divides the coherent light into a plurality of luminous fluxes. The interference measurement probe 2 emits a plurality of irradiation luminous fluxes at different angles. The plurality of irradiation luminous fluxes form an interference fringe and the interference fringe is irradiated onto an objective 8. A light receiving section 3 is disposed at a position where a reflection luminous flux from the objective 8 interferes, and receives an interference light reflected from the objective 8, thereby outputting a light receiving signal which is converted to an electric signal.

Abstract: Provided is a signal formation apparatus for use in an interference measurement which is capable of achieving a simplicity of optical adjustments and a subminiature of the apparatus, as well as a reduction of an influence by a wavelength variation of a laser light to the utmost. A coherent light emitted from a light source section 1 is supplied to a light emission portion 3 via a connection section 2. The light emission portion 3 comprises a straight type incidence waveguide 32, a dividing waveguide 33, emission waveguides 34 and 35, and a phase modulation section 36, which are provided on an optical substrate 31. The light emission portion 3 performs a phase modulation for one of luminous fluxes and emits irradiation luminous fluxes while keeping the other luminous flux as it is. In an irradiation optical portion 4, these irradiation luminous fluxes are collimating and deflected, and irradiated onto a measurement spot of a scale section 5.

Abstract: An apparatus for opening and closing a mold is described herein, wherein a movable mold is revolved and pivotally moved in association with a mold opening and closing operation. When opened, the mold is maintained in a sideways position such that the mold surface faces outwardly. In this manner, the molded article recovery operation is simplified, and monitoring of the mold surface by an industrial television set (ITV) is facilitated. In the mold opening operation, the movable mold begins at a position opposed to a fixed mold. As the mold is opened, a pinion is rotatively driven by a rack which is moved downward in association with the mold opening operation. In this manner, a rotatable block is revolved and pivotally moved along with the movable mold to a position so that the movable mold and the molded article are pointed outwardly. Ejection pins may then be used to eject the molded article off the mold.

Abstract: An optical waveguide portion is provided on one surface of a substrate portion. A luminous flux for measurement is caused to be incident on one end face of the optical waveguide substrate, and only leaking light having passed through the substrate portion is received. The cross-sectional distribution of the refractive index of the optical waveguide portion is measured from changes in the received quantity of light.

Abstract: A method of patterning an optical device for an optical IC whose purpose is to diffract a light beam incident on one surface of a device substrate to cause a light beam to emerge from another surface of the device. In this method, a layer of a substance of variable refractive index is formed on an optical substrate, coherent light is caused to irradiate the layer from the direction of the normal to the surface which will be the incidence side of the device when it is used or from the opposite side, and coherent light is caused to irradiate the layer from the direction of the normal to the surface which will be the emergence side of the device when it is used or from the opposite side to form an interference pattern on the layer that performs diffraction.

Abstract: According to the present invention, there are provided a projection system for emitting luminous flux for measurement, a light receiving unit or a prism member furnished with a light receiving unit, and an optical waveguide substrate comprising a substrate portion and an optical waveguide portion formed on the substrate portion, the light receiving unit or the prism is brought into close contact with the optical waveguide substrate, luminous flux for measurement from the projection system is passed from one end of the optical wavegide portion and a part of the luminous flux for measurement is leaked toward the light receiving unit, whereby cross-sectional distribution of refractive index of the optical waveguide is measured by change of light quantity of the leaking light sensed at the light receiving unit in case an incident point of the luminous flux for measurement is moved.

Abstract: According to the present invention, there are provided a projection system having an optical axis inclined toward one end surface of an optical waveguide portion arranged on one side of a substrate portion and for irradiating luminous flux for measurement from one end surface of the optical waveguide portion, and a light receiving unit for receiving luminous flux leaking from the optical waveguide portion among the luminous fluxes for measurement, projected light is effectively utilized for measurement, whereby cross-sectional distribution of refractive index of the optical waveguide is measured by change of light quantity entering said light receiving unit in case an incident point of the luminous flux is moved.

Abstract: An output power and wavelength stabilizing apparatus of a semiconductor laser has an injection current supplying source adapted to supply injection current to a single-mode semiconductor laser, a first light receiving portion adapted to receive a part of the output power of the semiconductor laser through a first optical element with varying spectral characteristics in the wavelength area of the semiconductor laser and to output a first signal, a second light receiving portion adapted to receive a part of the output power of the semiconductor laser through a second optical element with varying spectral characteristics opposite to that of the first optical element and to output a second signal, a wavelength fluctuation detecting portion for producing a difference signal related to the first signal and the second signal and obtaining a fluctuation of the wavelength of the semiconductor laser based on the difference signal, an output fluctuation detecting portion for producing a signal related to the sum of the

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: 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: An apparatus for stabilizing the wavelength/output power of a semiconductor laser is disclosed.