Abstract: The problem to be overcome by the present disclosure is to reduce harmonic components included in output signals. A magnetic sensor includes a detecting magnetoresistance element and a canceling magnetoresistance element. A tilt angle formed by a magnetic sensing direction of the canceling magnetoresistance element with respect to a magnetic sensing direction of the detecting magnetoresistance element falls within a predetermined range. The predetermined range is defined by reference to either n×?/3 or n×?/3+?/2, where ? is an angle of rotation of a rotator corresponding to one cycle of a fundamental harmonic included in output signals of the detecting magnetoresistance element and n is a natural number equal to or greater than 1.

Abstract: A magnetic sensor includes a magneto-resistive element configured to output a signal and a detection circuit configured to receive the signal. The detection circuit includes a regulator configured to supply a potential to the magneto-resistive element, a first current path configured to electrically connect the magneto-resistive element to the regulator, a second current path, a switch, and a diagnostic circuit connected to the second current path. The second current path includes, and is configured to electrically connect the magneto-resistive element to the regulator via the resistor. The switch is configured to select one of the first current path and the second current path, and electrically connect the magneto-resistive element to the regulator via the selected one of the first current path and the second current path.

Abstract: A rotation detecting device includes first and second magnetic detection elements that output first and second signals and a detection circuit having the first and second signals input thereto. The detection circuit includes an automatic correction circuit that performs generating and updating of a correction value for correcting the and second signals. The automatic correction circuit is configured to stop the generating or the updating of the correction value in at least one of a case where a rotation direction of an object is changed to a reverse rotation direction from a normal rotation direction and a case where a rotation direction of the object is changed to the normal rotation direction from the reverse rotation direction.

Abstract: A magnetic sensor includes a magneto-resistive element configured to output a signal and a detection circuit configured to receive the signal. The detection circuit includes a regulator configured to supply a potential to the magneto-resistive element, a first current path configured to electrically connect the magneto-resistive element to the regulator, a second current path, a switch, and a diagnostic circuit connected to the second current path. The second current path includes, and is configured to electrically connect the magneto-resistive element to the regulator via the resistor. The switch is configured to select one of the first current path and the second current path, and electrically connect the magneto-resistive element to the regulator via the selected one of the first current path and the second current path.

Abstract: A rotation detecting device is configured to be used with a switch and detect rotation of a rotation shaft having a magnetic body attached thereto. The rotation detecting device includes a magneto-resistive element facing the magnetic body and outputting a first signal related to displacement of the magnetic body, a Hall element facing the magnetic body and outputting a second signal related to displacement of the magnetic body, and a detection circuit having the first and second signals input thereto. The detection circuit is configured to: output the first signal while the switch is turned on; detect rotation-number information corresponding to the number of rotations of the rotation shaft based on the second signal at a first time point at which the switch is turned off; store the rotation-number information; and output the stored rotation-number information at a second time point when the switch is turned on after the first time point.

Abstract: The present disclosure provides a magnetic sensor with improved accuracy or reliability. The magnetic sensor includes a first magnetism detection element that outputs a first detection signal, a second magnetism detection element that outputs a second detection signal, and a detection circuit that receives the first and second detection signals. The detection circuit corrects the first detection signal for each section in a ( 1/16n) period of the first detection signal, when n is a natural number. With this configuration, the magnetic sensor has high accuracy or high reliability, and therefore is useful as, for example, a magnetic sensor used for detecting a steering angle and the like of a vehicle.

Abstract: A rotation detecting device includes first to fourth magneto-resistive elements that are provided on a first substrate to constitute a bridge circuit, a detection circuit provided on a second substrate, first to fourth wirings each connecting between the detection circuit and respective one of ends of the first to fourth magneto-resistive elements, first to fourth nodes provided on the second substrate, and first and second amplifiers provided on the second substrate. The first node combines signals on the first and second wirings. The second node combines signals on the third and fourth wirings. The first and second amplifiers amplify signals at the first and second nodes, respectively.

Abstract: A rotation detecting device includes first and second magnetic detection elements that output first and second signals and a detection circuit having the first and second signals input thereto. The detection circuit includes an automatic correction circuit that performs generating and updating of a correction value for correcting the and second signals. The automatic correction circuit is configured to stop the generating or the updating of the correction value in at least one of a case where a rotation direction of an object is changed to a reverse rotation direction from a normal rotation direction and a case where a rotation direction of the object is changed to the normal rotation direction from the reverse rotation direction.

Abstract: A rotation detecting device is configured to be used with a switch and detect rotation of a rotation shaft having a magnetic body attached thereto. The rotation detecting device includes a magneto-resistive element facing the magnetic body and outputting a first signal related to displacement of the magnetic body, a Hall element facing the magnetic body and outputting a second signal related to displacement of the magnetic body, and a detection circuit having the first and second signals input thereto. The detection circuit is configured to: output the first signal while the switch is turned on; detect rotation-number information corresponding to the number of rotations of the rotation shaft based on the second signal at a first time point at which the switch is turned off; store the rotation-number information; and output the stored rotation-number information at a second time point when the switch is turned on after the first time point.

Abstract: A rotation detecting device includes first to fourth magneto-resistive elements that are provided on a first substrate to constitute a bridge circuit, a detection circuit provided on a second substrate, first to fourth wirings each connecting between the detection circuit and respective one of ends of the first to fourth magneto-resistive elements, first to fourth nodes provided on the second substrate, and first and second amplifiers provided on the second substrate. The first node combines signals on the first and second wirings. The second node combines signals on the third and fourth wirings. The first and second amplifiers amplify signals at the first and second nodes, respectively.

Abstract: An infrared sensor, which achieves a low manufacturing cost, or has high sensitivity, or in which an increase in heat capacity is reduced, is provided. The infrared sensor includes a first infrared absorbing portion, an infrared sensing portion for sensing infrared rays based on infrared rays absorbed by the first infrared absorbing portion, and a plurality of protrusions including metal and disposed apart from each other on a surface of the first infrared absorbing portion. Since an absorption rate of infrared rays is improved, sensitivity can be improved, or an increase in heat capacity can be reduced.

Abstract: An infrared sensor, which achieves a low manufacturing cost, or has high sensitivity, or in which an increase in heat capacity is reduced, is provided. The infrared sensor includes a first infrared absorbing portion, an infrared sensing portion for sensing infrared rays based on infrared rays absorbed by the first infrared absorbing portion, and a plurality of protrusions including metal and disposed apart from each other on a surface of the first infrared absorbing portion. Since an absorption rate of infrared rays is improved, sensitivity can be improved, or an increase in heat capacity can be reduced.

Abstract: A magnetic sensor has a first tube-shaped bias magnet and a first magnetic sensor element. The first tube-shaped bias magnet has a bottom face, a top face facing the bottom face, and an outer side surface and an inner side surface both located between the bottom face and the top face, and includes an N pole formed by magnetizing one of the bottom face and the top face and an S pole formed by magnetizing a remaining one of the bottom face and the top face. The first magnetic sensor element is located in an inner space surrounded by a plane including the bottom face, a plane including the top face, and the inner side surface. The magnetic sensor can detect intensity of an external magnetic field with high accuracy.