Abstract: A circuit relies on the natural time constant presented to a pulse input signal which drops the signal level to a very low value “zero state,” less than 0.1 percent of the peak value, before the next pulse arrives. The signal is amplified with a low-noise, wideband, AC-coupled amplifier and split into two equal signals. One of the signals is delayed relative to the other by a fraction of the repetition period and then both signals are input to separate very wideband track-and-hold circuits. Output signals from the track-and-hold circuits are amplified, subtracted and applied to the input of an analog-to-digital converter. The track-and-hold circuits are clocked in such a way that one track-and-hold holds the value at the peak of the signal and the other track-and-hold holds the value at the baseline of the signal, the point when the signal has decayed to the zero state.

Abstract: A device has at least two current mode logarithmic amplifiers having currents as their inputs, and multiplexing logic electrically connected to outputs of the current mode logarithmic amplifiers to select one of the current mode amplifiers to produce an output signal.

Abstract: A spatial frequency reproducing apparatus includes a light source, a first means for modulating a light emitted from the light source into two lights having different frequencies and separately irradiated adjacently, a second means for two-dimensionally scanning the two lights, a third means for irradiating an object under measurement with the two lights, a fourth means for receiving and converting into an electrical signal at least two or more divided lights from the object under measurement with a boundary line being interposed therebetween in a direction substantially perpendicular to the direction separating the two lights, a fifth means for amplifying respective photoelectrically converted electrical signals while varying a degree of amplification according to frequencies thereof and generating a difference signal or a summation signal of the amplified signals, and a sixth means for obtaining a phase difference or an intensity difference of these signals to obtain a measurement value.

Abstract: In one embodiment, an ambient light sensor with first and second photo-detectors is disclosed. The first and second photo-detectors may have different depths and respond differently to light having a specific wavelength. The ambient lights sensor may further comprise a circuit configured to detect light of a specific wavelength. In another embodiment, the first and second photo-detectors may be configured such that each of the first and second photo-detectors detects coupling current from each other. In yet another embodiment, in addition to the first and second photo-detectors, a third photo-detector may be formed proximate to at least one of the first and second photo-detectors such that coupling photo-current is detected therein by the at least one of the first and second photo-detectors.

Abstract: According to one embodiment, an optical coupling device is provided. A first photodiode receives an optical signal generated by a light emitting element and converts the optical signal into a first electrical signal. A first inverting amplifier is provided with a first feedback resistor and a first operating amplifier connected in parallel with each other. The input end is connected to a cathode of the first photodiode. A first signal which is obtained by inverting the first electrical signal is output from the output end. A second inverting amplifier is provided with a second feedback resistor and a second operating amplifier connected in parallel with each other. The input end of the second inverting amplifier is connected to a cathode of a second photodiode. The second inverting amplifier outputs a second signal from the output end. A comparator receives the first and second signals and outputs a comparison amplified signal.

Abstract: In some embodiments, apparatus and systems, as well as methods, may operate to receive radiation at an active detector of a pair of radiation detectors to provide a first signal proportional to an intensity of the radiation, to receive none of the radiation at a blind detector of the pair of radiation detectors to provide a second signal proportional to the reception of no radiation, and to combine the first signal and the second signal to provide an output signal representing the difference between the first signal and the second signal. The pair of radiation detectors may comprise thermopile detectors. Combination may occur via differential amplification. Additional apparatus, systems, and methods are disclosed.

Abstract: A photo sensor includes a light incidence unit including a plurality of light incidence layers, the light incidence unit having a varying light transmittance with respect to external light, and a photo sensing unit including a plurality of photo sensing elements, the photo sensing unit being configured to output electrical signals in accordance with an amount of light transmitted through the light incidence unit to determine intensity of the external light, each of the photo sensing elements being configured to output electrical signals in accordance with light transmitted through a respective light incidence layer.

Abstract: A pixel section Pm,n includes a photodiode PD, a first capacitance section C1, a second capacitance section C2, and transistors T1-T6. The transistor T1 transfers the electric charge generated by the photodiode PD to the first capacitance section C1. The transistor T2 transfers the electric charge generated by the photodiode PD to the second capacitance section C2. The amplification transistor T3 outputs a voltage value corresponding to the amount of electric charge accumulated in the first capacitance section C1. The transistor T4 selectively outputs to the wiring L1,n the voltage value outputted from the amplification transistor T3. The transistors T3 and T4 constitute a source follower circuit. The transistors T5 and T6 selectively output to the wiring L2,n the electric charge accumulated in each of the first capacitance section C1 and the second capacitance section C2.

Abstract: The present invention provides an information processing device, having a power generating element for converting light into power, for performing processing responsive to an environment in which a wavelength of illuminating light changes. The device includes a plurality of power generating elements whose power generating efficiencies are deflected with respect to light having different predetermined wavelengths, respectively; a plurality of voltage detecting sections for detecting voltages of power generated by the plurality of power generating elements, respectively; a determining section for determining any of the plurality of power generating elements, whose power generating efficiency is different relative to the others on the basis of the respective detected voltages of the plurality of power generating elements, to determine a surrounding environment on the basis of a determination result; and a processing section for performing processing responsive to the determined surrounding environment.

Abstract: A receiver for an optics telecommunication system, the receiver comprises a first receiving device and means for focusing a received light beam carrying a signal towards such first receiving device. The receiver is characterized in that it further comprises at least a second receiving device and a beam splitter for splitting the focused light beam partially towards the first receiving device and partially towards the at least second receiving device. Tipically, the first receiver device is an APD diode while the second receiver device is a PIN diode. The telecommunication system is a Free Space Optics telecommunication system. A method is also described. The invention results in a high dynamic receiver. The dynamic of the invention receiver could be up to the sum of the dynamics of receivers provided with single receiving device (APD or PIN).

Abstract: A laser receiver detects a thin beam of laser light and distinguishes between the beam of laser light and an omni-directional pulse of light from a strobe by the use of an additional photo-detector. The device takes into account the possibility that the additional photo-detector could be illuminated simultaneously with the main photo-detectors at the end of the main photo-detectors closest to the additional photo-detector.

Abstract: A laser receiver for detecting the position of incidence of a beam of laser light thereon includes a first photodetector and a second photodetector aligned in series with each other and spaced apart from each other by a gap. If the laser is evenly distributed between the two photodetectors, then the laser position will be set as the correct position and a corresponding signal will be displayed. However, if the first photodetector detects more light than the second photodetector, then a signal will also be displayed to inform the user that more laser is being projected onto the first photodetector. On the other hand, if the second photodetector detects more light than the first photodetector, then a signal will be displayed to inform the user that more laser being projected onto the second photodetector. These signals will assist users to adjust the laser receiver to accurately position the laser.

Abstract: Receiver circuits are provided for detecting a target light source such as a swept laser beam. The circuits include a photodetector adapted to produce a first detector output signal and a second detector output signal where the relative amplitudes of the first and second detector output signals are related to the position of a swept laser beam impinging thereon. A first log signal is determined, which is based upon a logarithmic and optionally scaled calculation utilizing the first detector output signal. Correspondingly, a second log signal is determined, which is based upon a logarithmic and optionally scaled calculation utilizing the second detector output signal. The position of the beam is then computed based upon a subtraction of the second log output signal from the first log output signal.

Abstract: A laser receiver detects a thin beam of laser light and distinguishes between the beam of laser light and an omni-directional pulse of light from a strobe by the use of an additional photo-detector. The device takes into account the possibility that the additional photo-detector could be illuminated simultaneously with the main photo-detectors at the end of the main photo-detectors closest to the additional photo-detector.

Abstract: A laser receiver detects a thin beam of laser light and distinguishes between the beam of laser light and an omni-directional pulse of light from a strobe by the use of an additional photo-detector. The device takes into account the possibility that the additional photo-detector could be illuminated simultaneously with the main photo-detectors at the end of the main photo-detectors closest to the additional photo-detector.