Abstract: An optical density measuring apparatus for measuring density of a gas or a liquid to be measured includes a light source capable of irradiating light into a core layer, a detector capable of receiving light propagated through the core layer, and an optical waveguide that includes a substrate and the core layer. The core layer includes a light propagation unit and a first diffraction grating unit that receives light from the light source and guides the light to the light propagation unit, which includes a propagation channel capable of propagating light in an extending direction of the light propagation unit. The first diffraction grating unit is disposed near to and facing a light-emitting surface of the light source. The first diffraction grating unit includes first diffraction gratings, at least two of which receive light emitted from the same light-emitting surface of the light source.

Abstract: A gas sensor includes, in a single housing section, a substrate mounting surface 31 mounted with a substrate including a light emitter and a light receiver and a mirror section including plural reflectors. Then, in the housing section, all of the plural reflectors are integrally molded on an inner surface of the housing section to multiple reflect light emitted from the light emitter and cause the light to enter the light receiver in an opposing direction of one side and the other side in an extension direction of the substrate mounting surface.

Abstract: To reduce the error in a rotational angle detected by a rotational angle detection apparatus, provided is a rotational angle detection apparatus that detects a rotational angle of a magnetic field generation source, including a magnetic field detection apparatus that detects magnetic field components in at least two directions, and outputs resulting detection data; a correction value calculating section that calculates correction values for correcting an angle error of the rotational angle, based on a steady-state error that does not depend on rotation of the magnetic field generation source; and an angle computing section that calculates the rotational angle of the magnetic field generation source based on the detection data and the correction values, and outputs an angle signal indicating the rotational angle.

Abstract: Provided is a rotation angle detection device configured to detect a rotation angle of a magnetic field generation source, based on a magnetic field in at least two directions detected by a magnetic field detection device. The rotation angle detection device includes a correction value calculation unit configured to calculate a correction value of the rotation angle; an angle output unit configured to output an angle output signal indicative of the rotation angle of the magnetic field generation source, based on a magnetic field detection signal to be output from the magnetic field detection device and the correction value; and a filter unit capable of selecting a first filter characteristic, which is to be used for outputting the angle output signal, and a second filter characteristic, which is to be used for calculating the correction value and is different from the first filter characteristic.

Abstract: The present invention is directed to a gas detector configured to improve response speed of a gas sensor. A gas detector includes a housing, a gas sensor main body installed in the housing, and a partition wall provided in the housing and limiting the surrounding of the gas sensor main body to separate from the other area. The housing or the partition wall includes an opening portion directly connected from the outside to an area inside the partition wall.

Abstract: An optical concentration measurement device includes an LED light source, alight receiving unit having a rectangular light receiving surface and outputting a detection signal representing intensity of received light, and light guiding units guiding light emitted by the LED light source to the light receiving unit, wherein a shape on the rectangular light receiving surface of light radiated on the light receiving surface is rectangular, the optical concentration measurement device measures concentration of an object to be measured existing in a light path formed by the light guiding units, based on the detection signal output from the light receiving unit, and the light guiding units guide light at a diffraction limit or greater in such a way that area of the light on the rectangular light receiving surface is ½ or less of area of the rectangular light receiving surface.

Abstract: An optical density measuring apparatus and an optical waveguide capable of increasing the degree of design freedom are provided. The optical density measuring apparatus is for measuring density of a gas or a liquid to be measured and includes a light source capable of irradiating light into a core layer, a detector capable of receiving light propagated through the core layer, and an optical waveguide. The optical waveguide includes a substrate and the core layer, which includes a diffraction grating unit and a light propagation unit capable of propagating light in an extending direction of the light propagation unit. The diffraction grating unit and a portion of the core layer are separated in the thickness direction of the optical waveguide.

Abstract: A rotation angle sensor includes first and second magnetic detection elements disposed at positions where a first disposition angle relative to a magnet center is greater than 0 degrees and less than 90 degrees and configured to acquire magnetic field in a first direction varying by a rotation of a magnet; third and fourth magnetic detection elements configured to acquire the magnetic field in a second direction; a calculation signal generator configured to output a first magnetic field calculation signal, based on outputs of the first and second magnetic detection elements, and configured to output a second magnetic field calculation signal, based on outputs of the third and fourth magnetic detection elements; and an angle signal generator configured to generate and output an angle signal indicative of a rotation angle of the magnet, based on the first and second magnetic field calculation signal.

Abstract: A magnetic sensor device includes a composite chip component, and a sensor chip mounted on the composite chip component. The sensor chip includes a first magnetic sensor, a second magnetic sensor, and a third magnetic sensor that detect components of an external magnetic field that are in directions parallel to an X direction, parallel to a Y direction, and parallel to a Z direction, respectively. The composite chip component includes a first magnetic field generator, a second magnetic field generator, and a third magnetic field generator for generating additional magnetic field components that are in directions parallel to the X direction, parallel to the Y direction, and parallel to the Z direction, respectively.

Abstract: An optical concentration measurement device includes an LED light source, alight receiving unit having a rectangular light receiving surface and outputting a detection signal representing intensity of received light, and light guiding units guiding light emitted by the LED light source to the light receiving unit, wherein a shape on the rectangular light receiving surface of light radiated on the light receiving surface is rectangular, the optical concentration measurement device measures concentration of an object to be measured existing in a light path formed by the light guiding units, based on the detection signal output from the light receiving unit, and the light guiding units guide light at a diffraction limit or greater in such a way that area of the light on the rectangular light receiving surface is ½ or less of area of the rectangular light receiving surface.

Abstract: An LNA circuit includes: paths provided between an input and an output terminals, an LNA provided in at least one path, and a selector selecting one path. The LNA includes: a MOS transistor coupled between a first and a second power supplies, a first inductor coupled to a source of the MOS transistor, a capacitor formed between a gate and the source of the MOS transistor, a second inductor coupled between the gate of the MOS transistor and the input terminal, and a changeover switch coupled parallelly with at least one of the capacitor, and the first and the second inductors. The selector switches between a first state that one path is selected and the changeover switch is on, and a second state that another path is selected and the changeover switch is off. Alternatively, the one path and the another path are respectively provided without and with the LNA.

Abstract: A gas detection apparatus 1 includes a substrate 2; a light emitting element 3 provided on a main surface of the substrate for emitting light; a light receiving element 4 provided on the main surface of the substrate 2 for receiving the light; a light guide member 5 for guiding the light emitted by the light emitting element 3 to the light receiving element; a first joint member 6; and a second joint member 7. The first joint member joins the substrate and the light guide member, limits a displacement in a direction parallel and/or orthogonal to the main surface of the substrate. The second joint member joins the substrate and the light guide member, limits a displacement of the light guide member in a direction parallel to the main surface of the substrate and/or limits a displacement within a plane orthogonal to the main surface of the substrate.

Abstract: Provided is a device connected to a clock and data signal lines, comprising: a voltage input unit configured to be inputted with a clock signal as an input signal from the clock signal line and to generate first reference voltage corresponding to a high level of the clock signal; a reference voltage generation unit configured to be inputted with predetermined input voltage and to generate second reference voltage; a voltage regulation unit for generating regulation voltage by using the second reference voltage to convert a level of the first reference voltage; a drive unit for stepping down the regulation voltage to generate output voltage; a control unit; and an output unit connected with the control unit, the drive unit, and the data signal line, for outputting the output voltage to the data signal line in response to input of a high level of a control signal from the control unit.

Abstract: A successive approximation (SA) AD converter includes a SA control circuit generating a digital output signal based on an output from a comparator; a first capacitor coupled to an input of the comparator, receiving an analog input signal, and capable of storing electric charges; a second and a third capacitor groups coupling to a reference voltage and storing electric charges previously. The SA control circuit operates for each SA step that the second or the third capacitor group is coupled to a non-inverting input of the comparator and the other is coupled to an inverting input of the comparator based on the output from the comparator. The SA control circuit operates that capacitor terminals of the second and the third capacitor groups coupled to the input of the comparator have the same potential when the reference voltage is stored previously in the second and the third capacitor groups.

Abstract: A successive approximation analog-digital (AD) converter and method performed by the converter are provided. The successive approximation AD converter comprises a digital-analog (DA) converter; a comparator which determines a magnitude relation between an input signal and an output signal of the DA converter; and a successive approximation register which generates a first digital signal based on a determination result. The method comprises: switching an operation selection signal from a first logic to a second logic; performing a logical operation so that a digital signal input to the DA converter has a larger value or a smaller value than the first digital signal, when the operation selection signal has transited to the second logic, based on a portion of the determined first digital signal until transition; and inputting the first digital signal to the DA converter when the operation selection signal is the first logic.

Abstract: A stable and highly accurate gas detections apparatus is provided. A gas detection apparatus 1 includes a light emitting element 3 provided on a main surface 20 of the substrate 2 for emitting light from a light emitting surface 31; a light receiving element 4 provided on the main surface 20 of the substrate 2 for receiving the light on a light receiving surface 41; and a light guide member 5 for guiding the light emitted by the light emitting element 3 to the light receiving element 4. In plan view of the main surface of the substrate, the light emitting surface 31 and the light receiving surface 41 are shaped to have corners, and side of the light emitting surface 31 after being subjected to a magnification or reduction and a translation do not overlap sides of the light receiving surface 41.

Abstract: Provided is a gas detection apparatus which suppresses occurrences of distortions of the optical path to reduce fluctuations of the gas detection sensitivity. A gas detection apparatus 1 includes a substrate 2; a light emitting element 3 disposed in a first region 21 in a main surface 20 of the substrate 2 for emitting light; a light receiving element 4 disposed in a second region 22 in the main surface 20 of the substrate 2 for receiving the light; a light guide member 5 for guiding the light emitted by the light emitting element 3 to the light receiving element 4; and a joint member 6 joining the substrate 2 and the light guide member 5. The joint member 6 serves as a rotation axis when the light guide member 5 is displaced relative to the substrate 2.

Abstract: A gas sensor module (100) includes an infrared light emitting diode (10) configured to emit infrared light in accordance with a drive current, a quantum infrared sensor (20) configured to detect infrared light that passes through a detection target gas, a drive circuit (30) configured to output the drive current to the infrared light emitting diode (10), a charging circuit (50) to be connected to a power source and configured to output a charge current having a smaller current amount than the drive current, and a capacitor (40) configured to charge by the charge current being supplied from the charging circuit (50) and discharge by supplying the drive current to the drive circuit (30).

Abstract: Provided are a semiconductor wafer, a semiconductor device, and a gas concentration measuring device having a size reduced by reducing warpage to be even smaller than the sizes that can be achieved by conventional techniques. The semiconductor wafer includes: a wafer substrate, a semiconductor stacked portion formed on a first surface of the wafer substrate, the semiconductor stacked portion being capable of emitting or receiving infrared light of 2 ?m to 10 ?m; and an optical filter formed on a second surface of the wafer substrate that is opposite to the first surface of the wafer substrate. The thickness Twaf [?m] of the wafer substrate and the thickness Topt [?m] of the optical filter satisfy the relations of Topt?4 and Topt?0.000053× Twaf2.0488.