Abstract: A motion-detecting module with a built-in light source includes a chip unit, a cover unit, and a light-guiding unit. The chip unit has a PCB, a light-emitting chip, and an image-sensing chip. The light-emitting chip and the image-sensing chip are electrically disposed on the PCB. The cover unit is covered on the image-sensing chip, and the cover unit has a first opening for exposing the image-sensing chip. The light-guiding unit is disposed on a bottom side of the cover unit, and the light-guiding unit has a surface having a reflective layer thereon with a concave structure. The surface and the reflective layer are formed a reflective surface for reflecting and condensing beams generated from the light-emitting chip. Therefore, the beams are reflected via the reflective surface to form first beams, and the first beams are reflected via the object surface to form second beams that project onto the image-sensing chip.

Abstract: “Method and apparatus entraining interactive media players into a sustained experience of “Kinesthetic Spatial Sync,” defined as a perceived simultaneity and spatial superposition between a non-tactile, full body (“free-space”) input control process and immersive multisensory feedback. Asynchronous player input actions and (MIDI tempo) clock-synchronous media feedback events exhibit a seamless synesthesia1 or multisensory events fused into an integral event perception, this being between musical sound (hearing), visual responses (sight), and body kinesthetic (radial extension, angular position, height, speed, timing, and precision). This non-tactile interface process and multisensory feedback “look and feel” is embodied as an optimal ergonomic human interface for interactive music and as a six-degrees-of-freedom full-body-interactive immersive media controller.

Abstract: A design structure for designing, manufacturing, and/or testing a circuit for widening a dynamic range of sensor circuitry for sensing energy, such as light energy. The sensor circuitry includes a sensor and recharge circuitry for sharing additional charge with the sensor as needed during an integration period. Readout circuitry is provided to read out, after the integration period, the sense voltage remaining across the sensor and recharge information indicating whether the recharge circuitry shared charge with the sensor during the integration period. The sense voltage and recharge information read out of the sensor circuitry is used in a function to determine the total amount of energy sensed by the sensor during the integration period.

Abstract: An ambient light sensor circuit and a flat panel display device having same that can automatically control screen brightness by sensing ambient brightness and controlling an output current.

Abstract: Sensors and techniques useful with operating an automated data acquisition and notification system having a plurality of receptacles adapted to store items. In each of the plurality of receptacles, at least one sensor is operated to detect a presence of an item in that receptacle. Light is emitted from a planar surface within the receptacle to a space within the receptacle opposite the planar surface. While that light is emitted light incident on the planar surface is detected. A determination is made whether an amount of light that is detected is significant to indicate a presence of the item.

Abstract: A photo-sensitive element, a readout pixel with the photo-sensitive element, and a liquid crystal display with the readout pixels are described. The photo-sensitive element includes a switch TFT and a photo detecting device. The gate electrode of the switch TFT is electrically connected to a switch line and the source electrode of the switch TFT is electrically connected to a readout line. The photo detecting device is connected between the switch line and the drain electrode of the switch TFT for detecting the brightness of a light incident thereon. The photo detecting device is preferably a photo TFT, a photo diode, or a light sensitive resistor. The photo TFT and the switch TFT are preferably amorphous silicon transistors. The switch line is preferably a gate line disposed on the TFT array substrate of the liquid crystal display.

Abstract: Clock circuitry, for an electronic system including a component requiring a clock signal, comprises an opto-electronic oscillator for producing an optical clock signal at an optical clock output; and a feedback loop coupling the optical clock output back to the opto-electronic oscillator.

Abstract: A medical pump including an electromagnetic emitter and detector is provided. The emitter emits electromagnetic radiation of a predetermined wavelength. A pump set that is compatible with the medical pump modifies the emitted electromagnetic radiation when properly installed in the pump. The detector receives electromagnetic radiation, and a filter excludes electromagnetic radiation having a wavelength other than the predetermined wavelength. The pump monitors the filtered signal to determine whether the received electromagnetic radiation corresponds to the emitted electromagnetic radiation as modified by a properly loaded, compatible pump set and determines whether a compatible pump set is properly loaded in the pump as a function thereof.

Abstract: A vehicle rearview mirror system includes an electro-optic reflective element, an ambient light sensor that is operable to sense ambient light, a glare light sensor that is operable to sense glare light and a circuit that is responsive to the ambient glare light sensors which establishes a reflectance level of the reflective element. The circuit includes a sensor-responsive device and a controller. The sensor-responsive device produces an output that is a function of light sensed by glare and ambient light sensors. The controller connects one of the glare and ambient light sensors at a time with the sensor-responsive device to establish glare and ambient light levels and thereby the reflectance level of the reflective element. The mirror system may include a display operable to project light through the reflective element and may control the intensity of the display as a function of the glare light and ambient light.

Abstract: A temperature control apparatus is provided which may control temperature of an optical component that operates upon receipt of light from a light source. The apparatus may include a light quantity detector which detects a quantity of light based on the light source; and a temperature regulator which performs regulating operation for regulating the temperature of the optical component on the basis of the light quantity detected by the light quantity detector.

Abstract: A sensor that is photosensitive vis-à-vis at least part of the radiation in the visible range and/or in the near infrared range installed on a vehicle, the sensor being associated with an objective having a first zone that is focused to infinity and a second zone focused in near field.

Abstract: An image integrated circuit includes a light sensor layer and a semiconductor circuit layer. The light sensor layer receives and converts the light of a photographed image and into a corresponding light-induced electrical signal. The bottom of the light sensor layer form conductive terminals for supplying the light-induced electrical signal to the semiconductor circuit layer formed on the bottom of the light sensor layer. The semiconductor circuit layer receives and processes the light-induced electrical signal and in turn generates digital image signal/data so as to realize reconstruction of the image realistically, reducing the cost to produce and layout semiconductor circuits, and reducing the size of the image integrated circuit.

Abstract: A memory card including a first memory responsible for the main memory of the memory card, a memory control unit adapted to control the operation of the first memory, a photoelectric voltage generating unit adapted to generate a voltage corresponding to light irradiated externally via photoelectric conversion, a display unit having a second memory adapted to store information set in advance and adapted to display the information set in advance, and a display control unit adapted to control the operation of the display unit. The method of displaying information includes generating a voltage corresponding to light irradiated externally via photoelectric conversion and displaying information set in advance via a display unit of the memory card using the voltage by photoelectric conversion.

Abstract: A photodetector has a photo-receiving portion for receiving a return beam consisting of a main beam, a leading sub beam, and a trailing sub beam to produce photo-received signals and a processing circuit for processing the photo-received signals to produce main and sub processed signals. The photo-receiving portion includes a group of leading sub photo-receiving elements for receiving the leading sub beam to produce leading sub photo-received signals and a group of trailing sub photo-receiving elements for receiving the trailing sub beam to produce trailing sub photo-received signals. The processing circuit is configured to produce, in a normal mode, as the sub processed signals, added signals obtained by adding the leading sub photo-received signals and the trailing sub photo-receiving signals and to produce, in a test mode, as the sub processed signals, signals obtained by processing only the leading photo-received signals.

Abstract: A wireless remote control is provided for an auto-darkening lens (ADL) system used in a welding helmet, respirator system or other device to control or to adjust settings of an ADL of a controllable light shutter. A display system facilitates providing information indicating the operative settings and/or conditions of the controllable light shutter. A wired remote control for controlling or adjusting an ADL also uses a display system with indicators to indicate the operative settings and/or conditions of the ADL. The display may include a number of indicators, an alpha-numeric display, a heads-up display or other display. The display may include discrete indicators in the peripheral field of view of one eye of a user a controllable. The invention also includes methods of using a remote control for an ADL and of making an ADL to provide for future use of a wireless remote control.

Abstract: A solid-state image pickup device has a photoelectric conversion part performing photoelectric conversion on incident light, a comparison part connected to an output terminal of the photoelectric conversion part to compare an output voltage of the photoelectric conversion part with a reference voltage, a capacitive element having one end connected to the output terminal of the photoelectric conversion part, and a control line connected to the other end of the capacitive element. In a signal storage period, a first control voltage is applied to the control line so as to make an electric potential at the output terminal of the photoelectric conversion part fall outside a transition region of the comparator. In a signal read period, a second control voltage is applied to the control line so as to make the electric potential at the output terminal of the photoelectric conversion part fall within the transition region of the comparator.

Abstract: There are provided a light-receiving element for receiving light reflected from an optical recording medium, an optical head using the element, and an optical recording/reproducing apparatus using the element. In particular, the light-receiving element can be manufactured at low cost and in a simple manner and is configured to receive light from a short-wavelength laser source (having a wavelength of 402 nm to 413 nm). The light-receiving element includes a silicon substrate in which a light-receiving portion is formed; a circuit board for mounting the silicon substrate; at least one or more wires for electrically connecting the silicon substrate and the circuit board; a cover layer for covering the wires; and an exposed portion for exposing the light-receiving portion outside.

Abstract: An electronic circuit, which has transistors disposed on a substrate, each transistor including an active layer made of thin-film polysilicon, includes a sensor that converts a measured quantity into a current value, a current-voltage conversion circuit that converts the current value into a voltage, and a voltage detection circuit that detects the voltage converted by the current-voltage conversion circuit and outputs a predetermined signal. The current-voltage conversion circuit includes a storage circuit and a range-switching circuit that switches a current-voltage conversion range of the current-voltage conversion circuit by switching the capacitance of the storage circuit.

Abstract: A spatial filter includes a number of photodetectors that generate individual signals in the time domain. The individual signals are subsequently divided and grouped to create the I and Q channels output from the spatial filter. Prior to the formation of the I and Q channels, a window function is used to shape the spatial response of the spatial filter.

Abstract: In preferred forms of the invention an array of MEMS mirrors or small mirrors inside an optical system operates closed-loop. These mirrors direct external source light, or internally generated light, onto an object—and detect light reflected from it onto a detector that senses the source. Local sensors measure mirror angles relative to the system. Sensor and detector outputs yield source location relative to the system. One preferred mode drives the MEMS mirrors, and field of view seen by the detector, in a raster, collecting a 2-D or 3-D image of the scanned region. Energy reaching the detector can be utilized to analyze object characteristics, or with an optional active distance-detecting module create 2- or 3-D images, based on the object's reflection of light back to the system. In some applications, a response can be generated. The invention can detect sources and locations for various applications.

Abstract: A gain-controlled transimpedance amplifier circuit that comprises a first gain unit including an input for receiving a first current and an output, a current source for providing a second current, a second gain unit including an input and an output, a first impedance unit of a first impedance coupled in parallel with the second gain unit, and a comparator including an output, a first input coupled to the output of the first gain unit, and a second input coupled to the output of the second gain unit.

Abstract: An electric screen for a projector is provided. The electric screen utilizes a photo-electric conversion apparatus to convert received photon energy into electric energy and stores the electric energy in a storage battery. A motor is driven by the electric energy stored in a storage battery to extend or retract a screen. The electric screen further has a switch, the electric screen cooperates with the projector more efficiently.

Abstract: An anti-glare eye protection apparatus includes an anti-glare eye protection plate, an optical detector, an electromagnetic wave sensor, an electromagnetic wave detector, a user interface, a main controller, and a light transmittance controller. The electromagnetic wave sensor senses an electromagnetic wave generated by a welding or cutting torch using at least two coils. The electromagnetic wave detector compares a signal received through the electromagnetic wave sensor with a reference value. The user interface includes a display for selecting or displaying one of the optical and electromagnetic wave detectors. The main controller applies an electromagnetic wave detector activation signal to the electromagnetic wave detector as the optical detector starts optical detection and monitors changes in a received electromagnetic wave signal based on output of the electromagnetic wave detector.

Abstract: A pulse oximeter for measuring arterial oxygen saturation levels is provided. The pulse oximeter includes an LED signal generator for transmitting one or more light signals to a testing medium and a photodetector signal generator for processing at least a portion of the light signal generated by the LED signal generator into a photocurrent. The pulse oximeter further includes an integrated information transmission component for transmitting information corresponding to the pulse oximeter and which is integrated with the pulse oximeter without requiring additional wiring. A processing system within the pulse oximeter can generate a voltage to the integrated information transmission component to read the information stored in the component without causing the LED signal generator to generate a signal.

Abstract: A light beam detection device includes a light-receiving element for receiving a light beam and outputting a detection signal. A light detection circuit generates and outputs a light-emission signal based on the detection signal. A light-emitting element emits light based on the light-emission signal. The light-receiving element and the light-emitting element are arranged on a detection member. A supporting member supports the detection member. A driving device moves the supporting member in a reciprocative manner in an X axis direction and a Y axis direction to form a detection region with the detection member. The light-emitting means forms an afterimage on the detection region when the light beam irradiates the detection region.

Abstract: Embodiments of a device and a technique are disclosed for locating the angular position of a radiating point source with respect to a detector comprising a point source of radiation, a variable transmissivity mask with pseudo-random variations, a multi-element detector and computing means for interpreting the detected image. The mask pattern, when illuminated by a point source of radiation, casts an image on the detector array. Computing means determine the pattern shift to allow determination of point source angular location in two dimensions. The mask transmissivity pattern and corresponding image vary in two dimensions, in such a manner as to yield two correlation peaks that indicate the incident angle in two dimensions. The differential shift and common mode shift in correlation peaks indicate the respective angles of incidence, allowing determination of the angular position of the light source.

Abstract: An image sensing apparatus performs a plurality of times of image sensing on a subject, superpose-combines the obtained plurality of subject images into one subject image. The apparatus has an image sensing unit that converts a subject optical image into an electric signal, an optical unit that changes a view angle, and a change unit that changes the position of the optical unit by a predetermined amount so as to widen the view angle by a predetermined amount, prior to the plurality of times of image sensing.

Abstract: Light sensors having a wide dynamic range are used in a variety of applications. A wide dynamic range light sensor includes an exposed photodiode light transducer accumulating charge in proportion to light incident over an integration period. Sensor logic determines a light integration period prior to the beginning of integration and the charge is reset. Charge accumulated by the exposed light transducer over the light integration period is measured and a pulse having a width based on the accumulated charge is determined.

Abstract: A mirror assembly for an articulated vehicle (1, 2) incorporates an image sensor which detects a specific image on the trailer so that as the vehicle (1, 2) turns left the image sensor maintains the image in its field of view and the mirror is automatically adjusted to maintain the driver's view.

Abstract: The invention relates to a method for producing radio frequency waves, whereby a pulse laser for producing light pulses having a predetermined spectrum of frequency modes and a predetermined recurrence frequency is operated. The light pulses of the pulse laser are detected by means of a detector device, and corresponding electrical output signals forming the radio frequency signals are produced. Said pulse laser is actuated in a stabilized manner by means of an optical reference signal in such a way that the recurrence frequency of the light pulse is fixed. The invention also relates to a radio frequency generator for implementing said method.

Abstract: A scan type exposure apparatus wherein a pattern of an original is lithographically transferred to a substrate sequentially while the original and the substrate are scanningly moved relative to exposure light, the apparatus including a photodetector disposed at a position optically conjugate with the original, and a storing device for storing correction information with respect to an output of the photodetector, in relation to different positions of the original to be illuminated with the exposure light, such that, in the lithographic pattern transfer, the output of the photodetector can be corrected by use of the correction information.

Abstract: A plurality of energy couplers (12) receives signals from an energy pulse, each of the energy couplers (12) having a defined field of view, the field of views of at least some of the energy couplers being overlapping. A transducer (14) converts the signals received from the energy pulse to voltage or current output signals that are then amplified. A threshold circuit (18) triggers when the amplitude of a signal caused by the energy pulse exceeds a predetermined level, and signal processing instrumentation (24) then calculates the source location and/or the intensity and/or the initiation time of the energy pulse based on the timing of the output signals associated with individual energy couplers (12).

Abstract: A circuit configuration provides a simple device that can be used to monitor the voltage potential between any two points within the fuel cell coolant system without loading (i.e. decreasing) the voltage being monitored. The monitoring circuit include a lamp electrically coupled to the coolant system and arranged in a light-tight package with a photoresistor. When the ionization voltage for the lamp is reached, a fully isolated signal is provided in the form of an abrupt resistance change in the photoresistor. Visual and audible indicators can be coupled to the monitoring circuit to indicate a coolant contamination condition.

Abstract: The invention relates to a device for compensating for fluctuations in the light which is emitted by a light source and propogates along a light path. The device has a first light-sensitive sensor. The sensor detects the intensity of the light at a first location along the light path in a spatially resolved manner and generates electrical image signals. Furthermore, a second light-sensitive sensor is provided, which detects the intensity of the light at a second location along the light path and generates electrical output signals.

Abstract: A method and apparatus for detecting material accretion and peeling in a system such as a plasma process chamber, including multiple optical sensors which are provided in the chamber above a gas distribution plate or other surface inside the chamber. The optical sensors are connected to a central process controller that is capable of terminating operation of the chamber and may be equipped with an alarm. In the event that the optical sensors detect asymmetries in brightness or light reflection among various portions or regions of the gas distribution plate or other surface, which asymmetries may indicate the formation of a material coating on the plate or dislodging of contaminant particles from the plate, a signal is sent to the process controller, which may be adapted to terminate the plasma process, alert operating personnel, or both.

Abstract: A method for determining an angle of incidence of periodic optical signals is provided. The method includes detecting whether the periodic optical signals are present; generating a pulsed output when the periodic optical signals are present, the pulsed output corresponding to peaks in the periodic optical signals; predicting a timing of the periodic optical signals from the pulsed output; controlling a gated detector array to take a first reading and a second reading of the periodic optical signals based upon the timing, the first reading being out of phase with the timing and the second reading being in phase with the timing; and generating the angle of incidence by filtering the first reading from the second reading.

Abstract: A photo-detecting semiconductor device according to an embodiment of the present invention has a first photodetector element and a second photodetector element placed adjacent to each other and isolated from each other to each generate an electric signal responsive to a received optical signal; a signal detecting circuit which amplifies the electric signal from said first photodetector element and outputs a detection-use electric signal to detect a predetermined optical signal received at said first photodetector element; a power supply circuit which starts the supply of power upon receiving said detection-use electric signal from said signal detecting circuit; and a signal output circuit supplied with power from said power supply circuit to amplify the electric signal from said second photodetector element and output an output-use electric signal. An electrical circuit has the photo-detecting semiconductor device.

Abstract: This invention relates to a radiographic apparatus which comprises a radiographic image photographing unit for photographing a radiographic image of an object irradiated with radiation by a radiation generating device, a distance measuring system for measuring the distances or distance from the radiation generating device to the radiographic image photographing unit and/or the object, and distance information indicating means for indicating distance information obtained by the distance measuring system.

Abstract: An X-ray flat panel detector includes sensor elements constituted by a plurality of effective pixels that detect X-rays and a plurality of dummy pixels that are arranged adjacent to the effective pixel area and generate electrical signals irrelevant to X-rays, signal lines which read out electrical signals from the respective pixels, scanning lines which scan the respective pixels, a first electrostatic wiring line which distributes static electricity accumulated in the signal lines, and a second electrostatic wiring line which distributes static electricity accumulated in the scanning lines. A plurality of dummy pixels are classified into a DA area where noise superposed on the signal lines are removed and a DB area where noise superposed on the scanning lines are removed. The first and second electrostatic wiring lines are laid out around the sensor elements, and physically disconnected between the DA area and the DB area.

Abstract: A measuring method for measuring current-voltage characteristics of a photoelectric conversion device by irradiating light to said photoelectric conversion device and a reference device corresponding to said photoelectric conversion device at the same time while detecting an irradiance of said light using said reference device, characterized in that a light responsive time constant of a irradiance detection circuit in which said reference device is used is adjusted so that said light responsive time constant of said irradiance detection circuit comes closer to a light responsive time constant of said photoelectric conversion device. An apparatus for practicing said measuring method.

Abstract: The invention relates to a method for producing radio frequency waves, whereby a pulse laser for producing light pulses having a predetermined spectrum of frequency modes and a predetermined recurrence frequency is operated. The light pulses of the pulse laser are detected by means of a detector device, and corresponding electrical output signals forming the radio frequency signals are produced. Said pulse laser is actuated in a stabilized manner by means of an optical reference signal in such a way that the recurrence frequency of the light pulse is fixed. The invention also relates to a radio frequency generator for implementing said method.

Abstract: An image acquisition system and method employing multi-axis integration (MAI) may incorporate both optical axis integration (OAI) and time-delay integration (TDI) techniques. Disclosed MAI systems and methods may integrate image data in the z direction as the data are acquired, projecting the image data prior to deconvolution. Lateral translation of the image plane during the scan in the z direction may allow large areas to be imaged in a single scan sequence.

Abstract: A method and apparatus for detecting material accretion and peeling in a system such as a plasma process chamber, including multiple optical sensors which are provided in the chamber above a gas distribution plate or other surface inside the chamber. The optical sensors are connected to a central process controller that is capable of terminating operation of the chamber and may be equipped with an alarm. In the event that the optical sensors detect asymmetries in brightness or light reflection among various portions or regions of the gas distribution plate or other surface, which asymmetries may indicate the formation of a material coating on the plate or dislodging of contaminant particles from the plate, a signal is sent to the process controller, which may be adapted to terminate the plasma process, alert operating personnel, or both.

Abstract: The present invention provides a simple device that can be used to monitor the voltage potential between any two points within the fuel cell coolant system without loading (i.e. decreasing) the voltage being monitored. The monitoring circuit include a lamp electrically coupled to the coolant system and arranged in a light-tight package with a photoresistor. When the ionization voltage for the lamp is reached, a fully isolated signal is provided in the form of an abrupt resistance change in the photoresistor. Visual and audible indicators can be coupled to the monitoring circuit to indicate a coolant contamination condition.

Abstract: A rear-view mirror driving and controlling mechanism comprising a rear-view mirror manipulator for moving the mirror angle position of the rear-view mirror, a reverse signal detector for generating reverse position signals when the transmission is shifted to the reverse position, a controller for moving the rear-view mirror angle on the basis of the operation status of a rear-view mirror manipulator and the detection result of the presence or absence of reverse position signals, a mirror angle detector for generating angle detection signals indicative of the mirror angle of the rear-view mirror, and a mirror angle storage for storing angle detection signals, wherein the controller stores the angle detection signals generated by the rear-view mirror angle detector into the mirror angle storage for each time the mirror angle position is adjusted at the time when the reverse detection signals are not generated, while moving down the rear-view mirror position angle at the time when the reverse detection signals a

Abstract: In a scanning microwave microscope including a microwave resonator, an exciting unit for exciting the microwave resonator, a first detecting unit for detecting a first detection amount relating to a resonant state of the microwave resonator, a sharp end coupled to a center conductor of the microwave resonator, and a display unit for displaying the first detection amount while a sample is scanned by the sharp end, a distance changing unit causes a differential change in a distance between the sharp end and the sample. A second detecting unit detects a second detection amount relating to a change of the first detection amount. A control unit controls the distance between the sharp end and the sample in accordance with the second detection amount, so that an average value of the distance between the sharp end and the sample is brought close to a definite value.

Abstract: To achieve a high density, high resolution, or size reduction, there is provided a solid-state image pickup device having a plurality of photoelectric conversion elements formed in a semiconductor substrate, conductive layers formed on the semiconductor substrate between the neighboring photoelectric conversion elements via an interlayer layer, a first interlayer layer formed on the photoelectric conversion elements and conductive layers, a second interlayer layer formed on the first interlayer layer, and microlenses formed above the photoelectric conversion elements, wherein the refraction index of the first interlayer layer located above the photoelectric conversion elements is different from that of the second interlayer layer.

Abstract: Systems and methods for use with an optical communication beam are disclosed. The system allows the beam of light to operate at an adequate power level that provides a robust optical link while minimizing any safety risk to humans. The system calibrates and controls the gain for an avalanche photodiode detector (APD). A detector circuit is used to calibrate the APD. Once calibrated, the detector circuit further provides an electrical bias to the APD to process or condition the electrical signal to produce a detector output. The systems and methods disclosed herein attenuate the power level of an incoming communication beam to prevent oversaturation of an APD. The system further provides an alignment signal, which is effective over a wide dynamic range of incoming power levels.

Abstract: An apparatus for use in automatically correcting distortion in an optical signal includes an optical relay element positioned to receive the optical signal from a remote source and to relay the optical signal; and a photosensor positioned to receive a portion of the optical signal from the optical relay element, and configured to produce an electronic signal that varies with the distortion in the optical signal. Processing circuitry is configured to receive the electronic signal from the photosensor to detect variations in the electronic signal caused by the distortion in the optical signal, and to generate a control signal in response to the variations. An adjustment element is configured to receive the control signal from the processing circuitry and, in response to the control signal, to correct the distortion in the optical signal.

Abstract: A photo-detecting semiconductor device according to an embodiment of the present invention has a first photodetector element and a second photodetector element placed adjacent to each other and isolated from each other to each generate an electric signal responsive to a received optical signal; a signal detecting circuit which amplifies the electric signal from said first photodetector element and outputs a detection-use electric signal to detect a predetermined optical signal received at said first photodetector element; a power supply circuit which starts the supply of power upon receiving said detection-use electric signal from said signal detecting circuit; and a signal output circuit supplied with power from said power supply circuit to amplify the electric signal from said second photodetector element and output an output-use electric signal. An electrical circuit has the photo-detecting semiconductor device.