Abstract: A distance measurement device includes: a signal acquisition unit to acquire an electric signal based on interference light from an optical sensor device that splits sweep light having a periodically changing frequency into reference light and irradiation light to be emitted toward an object to be measured, irradiates the object with the irradiation light, generates interference light by causing the reference light to interfere with reflected light that is the irradiation light reflected by the object, and generates the electric signal based on the generated interference light; a frequency calculation unit to calculate, on the basis of the electric signal based on the interference light, a peak frequency of the electric signal using LASSO regression; a distance measurement unit to measure, on the basis of the peak frequency, a distance from a predetermined reference point to the object; and a distance output unit to output distance information indicating the distance.

Abstract: An optical communication device is configured to include: a laser diode that outputs light; an EA modulator including a cathode and an anode, to modulate the light output from the laser diode on the basis of a high-frequency signal applied between the cathode and the anode; a resistor connected between the cathode and the anode; and a pattern line connected in series with the resistor and having an inductance component, in which each of the laser diode and the EA modulator is formed on a front surface of the high-frequency line substrate or a back surface of the high-frequency line substrate, and the pattern line is formed on a side face of the high-frequency line substrate.

Abstract: A high-frequency circuit is configured so as to include a printed circuit board and a flexible circuit board connected to the printed circuit board, wherein the printed circuit board includes: a first dielectric layer having a first surface and a second surface, a first ground conductor being formed on the first surface; a second dielectric layer having a third surface and a fourth surface, a second ground conductor being formed on the fourth surface; and first signal lines wired between the second surface and the third surface, the flexible circuit board includes: a third dielectric layer having a fifth surface and a sixth surface, a third ground conductor being formed on the fifth surface; a fourth dielectric layer having a seventh surface and an eighth surface, a fourth ground conductor being formed on the eighth surface; and second signal lines wired between the sixth surface and the seventh surface, and a connecting portion between the printed circuit board and the flexible circuit board includes: a plur

Abstract: A substrate has a front surface and a back surface opposite from the front surface. An n-type layer, a multiplication layer, a p-type electric field control layer, a light absorption layer, and a window layer are layered in order on the front surface. A p-type region is provided in part of the window layer. An anode electrode is provided on the p-type region and connected to the p-type region. An anode pad and a cathode pad are provided on the back surface. First and second connecting holes penetrates the substrate. A third connecting hole penetrates from the window layer to the n-type layer. The cathode pad is electrically connected to the n-type layer via the first connecting hole. The anode pad is electrically connected to the anode electrode via the second and third connecting holes. A light-receiving region is provided on the back surface.

Abstract: A substrate has a front surface and a back surface opposite from the front surface. An n-type layer, a multiplication layer, a p-type electric field control layer, a light absorption layer, and a window layer are layered in order on the front surface. A p-type region is provided in part of the window layer. An anode electrode is provided on the p-type region and connected to the p-type region. An anode pad and a cathode pad are provided on the back surface. First and second connecting holes penetrates the substrate. A third connecting hole penetrates from the window layer to the n-type layer. The cathode pad is electrically connected to the n-type layer via the first connecting hole. The anode pad is electrically connected to the anode electrode via the second and third connecting holes. A light-receiving region is provided on the back surface.

Abstract: An optical module includes: a stem; a temperature control module; a carrier; a light emitting element fixed on a light emitting element fixing surface of the carrier, having a front surface and a rear surface opposite to each other, emitting signal light from a first emission point in the front surface, and emitting back light from a second emission point in the rear surface; a light receiving element fixed on the carrier by a light receiving element fixing surface; a lens cap; and a lens, wherein a reflecting surface is provided on the carrier, the light receiving element receives the back light reflected by the reflecting surface, and a center of a light receiving surface of the light receiving element is positioned between the front surface and the rear surface in an optical axis direction of the signal light.

Abstract: A wavelength-multiplexing optical communication module includes: a substrate; a plurality of light sources on the substrate; a plurality of joint materials separately disposed on the substrate at positions respectively corresponding to the plurality of light sources; and a plurality of optical components fixed on the substrate by means of the plurality of joint materials respectively, wherein the substrate includes a plurality of forming portions which respectively form peripheries of the plurality of joint materials into shapes of circles or regular polygons having an even number of vertices.

Abstract: An optical module includes: a stem; a temperature control module; a carrier; a light emitting element fixed on a light emitting element fixing surface of the carrier, having a front surface and a rear surface opposite to each other, emitting signal light from a first emission point in the front surface, and emitting back light from a second emission point in the rear surface; a light receiving element fixed on the carrier by a light receiving element fixing surface; a lens cap; and a lens, wherein a reflecting surface is provided on the carrier, the light receiving element receives the back light reflected by the reflecting surface, and a center of a light receiving surface of the light receiving element is positioned between the front surface and the rear surface in an optical axis direction of the signal light.

Abstract: A terminal portion configured to obtain electrical connection with a printed circuit board includes a first signal pad that is formed in a first conductor layer and is electrically separated from a ground layer, a pair of first ground pads that is formed in the first conductor layer to sandwich the first signal pad and is connected to the ground layer, a second signal pad that is formed in a second conductor layer and is connected to a signal line, a pair of second ground pads that is formed in the second conductor layer to sandwich the second signal pad and is electrically separated from the signal line, a third signal pad formed in a third conductor layer, and a pair of third ground pads formed in the third conductor layer to sandwich the third signal pad. The second signal pad is wider than the third signal pad.

Abstract: A wavelength-multiplexing optical communication module includes: a substrate; a plurality of light sources on the substrate; a plurality of joint materials separately disposed on the substrate at positions respectively corresponding to the plurality of light sources; and a plurality of optical components fixed on the substrate by means of the plurality of joint materials respectively, wherein the substrate includes a plurality of forming portions which respectively form peripheries of the plurality of joint materials into shapes of circles or regular polygons having an even number of vertices.

Abstract: A method of manufacturing a wavelength multiplexing optical communication module which includes a plurality of light emitting elements, a plurality of optical lenses adjusting wavefronts of emergent lights from the plurality of light emitting elements, and a multiplexer combining the lights adjusted by the plurality of optical lenses, includes: applying a resin on a carrier so as to have a shape with a curvature symmetric about a rotation axis; and bonding a lower surface of the optical lens to the carrier with the resin, wherein a recess having a curvature is formed at a center of the lower surface of the optical lens.

Abstract: An optical module includes a light emitting element, an optical fiber, a wavelength separating filter that is arranged at a predetermined angle with respect to a longitudinal direction of the optical fiber on a plane including the longitudinal direction of the optical fiber, and a lens for focusing light emitted from the light emitting element on the optical fiber via the wavelength separating filter. The light emitting element is arranged while being offset in a direction perpendicular to a central axis of the lens on a plane where the wavelength separating filter has the predetermined angle with respect to the central axis of the lens.

Abstract: To provide an optical module and a light transmission method for controlling position shifts of a focal point easily and flexibly. An optical module comprises a lens, a lens cap and a transparent member. The lens causes laser light emitted from a semiconductor laser to be focused at a focal point. The lens cap supports the lens. The transparent member is anchored to the lens cap such that an asymmetric force centered on the optical axis of the lens is applied in accordance with thermal expansion. The transparent member is disposed on the optical path.

Abstract: An optical receiver is provided with a photoelectric converter that outputs an electrical signal according to light that is received by a light-receiving region. The optical receiver is provided with a condensing lens and optical filter that are located in an optical path from where signal light enters towards the light-receiving region. The condensing lens condenses the signal light onto the light-receiving region. The optical filter reflects light having a first wavelength that is included in the signal light using a front surface thereof and reflects light having a second wavelength that is included in the signal light using a rear surface thereof that faces the front surface so that the light is emitted through the front surface.

Abstract: At the time of assembly of an optical transmission/reception module, a test variable wavelength light source 22 for outputting a test light signal is connected to a connector 8 of an optical fiber 7, and a large-diameter PD 23 measures a transmission loss in a light wavelength band limiting filter 12 while a rotational position determining unit 24 rotates a fiber ferrule 5, so that the rotational position determining unit 24 determines the rotational position ?loss-min of the fiber ferrule 5 which minimizes the transmission loss in the light wavelength band limiting filter 12, and aligns the fiber ferrule 5 at the rotational position ?loss-min.

Abstract: To provide an optical module and optical transmission method that reduce tracking errors caused by position shifting of the focal point of light related to the optical axis direction, using a simpler method. A lens 1 causes light emitted from an emission point to be focused at a focal point. A lens cap 2 is provided on a stem 6 and supports the lens 1. A semiconductor laser 3 is provided on the stem 6 and emits light from a position corresponding to the emission point. A control member 7 controls position shifting of the focal point generated by thermal expansion of the lens cap 2, through thermal expansion in the direction of the optical axis of the lens 1.

Abstract: A terminal portion configured to obtain electrical connection with a printed circuit board includes a first signal pad that is formed in a first conductor layer and is electrically separated from a ground layer, a pair of first ground pads that is formed in the first conductor layer to sandwich the first signal pad and is connected to the ground layer, a second signal pad that is formed in a second conductor layer and is connected to a signal line, a pair of second ground pads that is formed in the second conductor layer to sandwich the second signal pad and is electrically separated from the signal line, a third signal pad formed in a third conductor layer, and a pair of third ground pads formed in the third conductor layer to sandwich the third signal pad. The second signal pad is wider than the third signal pad.

Abstract: An optical transmission/reception module including a filter holder on which filter mount surfaces for mounting wavelength division multiplexing filters and light wavelength band limiting filters are formed and in which a hole for guiding a light signal is formed in each of the filter mount surfaces incorporated into a housing. The wavelength division multiplexing filters and the light wavelength band limiting filters are mounted to the filter mount surfaces formed on the filter holder, respectively.

Abstract: An optical receiver is provided with a photoelectric converter that outputs an electrical signal according to light that is received by a light-receiving region. The optical receiver is provided with a condensing lens and optical filter that are located in an optical path from where signal light enters towards the light-receiving region. The condensing lens condenses the signal light onto the light-receiving region. The optical filter reflects light having a first wavelength that is included in the signal light using a front surface thereof and reflects light having a second wavelength that is included in the signal light using a rear surface thereof that faces the front surface so that the light is emitted through the front surface.

Abstract: A light-receiving-element module is provided which has a greater high-frequency characteristic and light receiving sensitivity than those of conventional technologies. A light-receiving-element module includes a first refractive part that refracts an optical signal with a first wavelength or an optical signal with a second wavelength, and a second refractive part that refracts the optical signal with the first wavelength and the optical signal with the second wavelength refracted by the first refractive part so as to reduce a chromatic aberration. The light-receiving-element module also includes a light receiving element that converts the optical signal with the first wavelength or the optical signal with the second wavelength refracted by the second refractive part into an electric signal by photoelectric conversion.