A circuit arrangement comprises a photo detector (2) for detecting electromagnetic energy and a signal generating means (4, 6, 12, 16) being suitable for generating a sequence of events wherein an event interval of the sequence depends on the detected electromagnetic energy. The signal generating means (4, 6, 12, 16) is coupled downstream of the photo detector (2). A counting means (30, 32, 34, 36) for measuring a time period until a given number of events has been generated is coupled downstream of the signal generating means (4, 6, 12, 16).

An optical sensor arrangement has an integrator, a photodiode for providing a current corresponding to a first polarity, a comparator coupled to the integrator for comparing a voltage with a threshold voltage to provide a comparison output, a reference charge circuit and a control unit. The reference charge circuit is coupled to the integrator for selectively providing first charge packages of a first size or second charge packages of a second size. The control unit is configured to control operation in a calibration phase, in an integration phase and in a residual measurement phase. During the calibration phase, the reference charge circuit provides one of the first charge packages and one or more of the second charge packages to the integrator until the comparison output changes. A reference number is determined corresponding to a number of the second charge packages provided. During the integration phase, the photodiode is connected to the integrator and the reference charge circuit provides one of the first charge packages to the integrator in response to a respective change of the comparison output. An integration number corresponding to a number of the changes of the comparison output is determined. During the residual measurement phase that immediately follows the integration phase, the reference charge circuit provides one or more of the second charge packages to the integrator until the comparison output changes. A residual number corresponding to a number of the second charge packages provided is determined.

An electromagnetic wave detecting apparatus is provided with: a plurality of detecting devices each of which is configured to detect an electromagnetic wave; a voltage applying device configured to apply bias voltage to each of the plurality of detecting devices; an obtaining device configured to obtain a detection signal outputted from each of the plurality of detecting devices; and a setting device configured to set acquisition timing of the detection signal for each of the plurality of detecting devices, on the basis of the bias voltage, which is applied to each of the plurality of detecting devices, and the detection signal of each of the plurality of detecting devices.

According to one aspect, embodiments herein provide a digital unit cell comprising a photodiode, an integration capacitor coupled to the photodiode and configured to accumulate charge generated by the photodiode responsive to an input light signal incident on the photodiode over an integration period, a comparator coupled to the integration capacitor and configured to compare a voltage across the integration capacitor with a voltage reference and to generate a clock signal at a first level each time a determination is made that the voltage across the integration capacitor is greater than the voltage reference, a shift register coupled to the comparator and configured to receive the clock signal from the comparator and increase a count value each time the clock signal at the first level is received from the comparator, and an output coupled to the shift register and configured to provide the count value to an external system.

An optical sensor arrangement comprises a photodiode (11), an integrator (12) with an integrator input (15) coupled to the photodiode (11), a comparator (13) with a first input (18) coupled to an integrator output (16) of the integrator (12), and a reference capacitor circuit (14) that is coupled to the integrator input (15) and is designed to provide a charge package to the integrator input (15). In a start phase (A), charge packages are provided to the integrator input (15), until a comparator input voltage (VIN) at the first input (18) of the comparator (13) crosses a comparator switching point.

A sensor system, device and method for generating a wireless signal in response to a sensed illumination. A sensor is disclosed having: a photosensitive element; a device that converts a sensed illumination detected by the photosensitive element into a corresponding impedance response; and a wireless signal generator that generates a wireless output based on a characteristic of the corresponding impedance response, wherein the wireless output correlates to the sensed illumination.

A light intensity detection circuit, a light intensity detector, a detection method thereof and a display device are provided. The light intensity detection circuit includes a first reverser, a second reverser, a third reverser, a photosensor and an energy storage element. The first reverser respectively outputs a voltage of the first voltage terminal or the second voltage terminal to the energy storage element under the control of the signal input terminal of the light intensity detection circuit. The second reverser and the third reverser are configured to control transmission of photocurrent generated by the photosensor along a first direction or a second direction. The energy storage element controls a voltage of the signal output terminal of the light intensity detection circuit through voltage storage or voltage release.

A circuit arrangement comprises a photo detector (2) for detecting electromagnetic energy and a signal generating means (4, 6, 12, 16) being suitable for generating a sequence of events wherein an event interval of the sequence depends on the detected electromagnetic energy. The signal generating means (4, 6, 12, 16) is coupled downstream of the photo detector (2). A counting means (30, 32, 34, 36) for measuring a time period until a given number of events has been generated is coupled downstream of the signal generating means (4, 6, 12, 16).

A light intensity detection circuit, a light intensity detector, a detection method thereof and a display device are provided. The light intensity detection circuit includes a first reverser, a second reverser, a third reverser, a photosensor and an energy storage element. The first reverser respectively outputs a voltage of the first voltage terminal or the second voltage terminal to the energy storage element under the control of the signal input terminal of the light intensity detection circuit. The second reverser and the third reverser are configured to control transmission of photocurrent generated by the photosensor along a first direction or a second direction. The energy storage element controls a voltage of the signal output terminal of the light intensity detection circuit through voltage storage or voltage release.

The following steps are performed in connection with a photodiode circuit: a) resetting the photodiode circuit; b) determining when a photodiode voltage changes in response to illumination to reach a threshold; and c) updating a counter in response to the determination in step b). The steps a) to c) are repeated until an end of a measurement period is reached. The value of the counter at the end of the measurement period is then output to indicate an intensity of the illumination.