Systems and methods are provided for measuring an ambient light level in a volume that is lighted by a pulsating light source. A first light sensor is configured to generate a first signal based on an amount of light detected in the volume. A bypass switch is configured to bypass the first light sensor at a first point in time when the light source is on and to not bypass the first light sensor at a second point in time when the light source is off. A second sensor is configured to generate a second signal based on an environment in the volume, and a difference circuit is configured to determine a difference magnitude between the second signal and the first signal to generate an ambient light signal.

A stroboscope with an integral optical reflective sensor, which can be removable or fixed, contains a light emitting source, a light sensitive receiver, a pulse conditioning circuit, a stroboscope circuit, a blanking circuit, and a stroboscope light source. The light emitting source projects a light beam to a reflective target. The reflected light beam from the reflective target is detected by the light sensitive receiver. The pulse conditioning circuit generates a set of electrical pulses coincident with the reflected light beam which are sent to the stroboscope circuit. Depending on the signal received by the stroboscope circuit, the stroboscope light source is triggered. The blanking circuit prevents false triggering of the stroboscope light source by introducing a time delay. The time delay is applied when the stroboscope light source is switched on and for a finite time after the stroboscope light source is switch off.

A light-modulated photodiode-based monitor for detecting a control signal of a display is disclosed. The monitor includes an emitter configured to emit a control signal, a polarizer configured to linearly polarize the pulsed signal, one or more fold mirrors configured to reflect the pulsed signal from the emitter onto a test portion and/or reflect the pulsed signal that has reflected off of the test portion. The monitor further includes an analyzer configured to block or transmit the polarized pulse signal reflected from at least one of the fold mirror or the test portion, and a detector configured to receive the pulsed signal transmitted from the analyzer and convert the pulsed signal into an electrical signal. The monitor further includes a controller that includes one or more processors and is configured to receive the electrical signal, filter and rectify the electrical signal, and determine a functional state of the display.

A system comprises a photodetector array (PDA) including a plurality of imaging pixels configured to generate electrical signals indicative of an imaged scene, and an integrated circuit (IC) operatively connected to the PDA to receive the electrical signals from the imaging pixels to form image data.

For calculating an optical sensor's regular-discharge probability, a light detection system includes the optical sensor, an application voltage generating circuit for applying a drive pulse voltage to the optical sensor, a discharge determining portion for detecting the optical sensor's discharge, a first discharge probability calculating portion, a sensitivity parameter storing portion for storing the optical sensor's sensitivity parameters, and a second discharge probability calculating portion for calculating a discharge probability of the optical sensor's regular discharge. The first discharge probability calculating portion calculates a discharge probability in: a first state in which light from an additional light source having a known light quantity is incident on the optical sensor or the additional light source is turned off; and a second state in which the additional light source's turning-on/turning-off status is different from the first state, with the drive pulse voltage's pulse width being the same as the first state.

In an embodiment a method for measuring ambient light includes successively synchronizing optical signal acquisition phases with extinction phases of a disruptive light source, wherein the disruptive light source periodically provides illumination phases and the extinction phases, accumulating, in each acquisition phase, photo-generated charges by at least one photosensitive pixel comprising a pinned photodiode, transferring the accumulated photo-generated charges to an integration node and integrating, for each pixel, the transferred charges on the integration node during a series of the successive acquisition phases.

A device may determine at least one metric related to a plurality of laser pulses associated with a Q-switched laser. The device may determine a statistical metric for the at least one metric related to the plurality of laser pulses. The device may determine that the statistical metric satisfies a threshold level of deviation of the at least one metric related to the plurality of laser pulses from a baseline value for the at least one metric. The device may indicate laser degradation of the Q-switched laser based on determining that the statistical metric satisfies the threshold.

A system for generating clock signals for a photonic quantum computing system includes a pump photon source configured to generate a plurality of pump photon pulses at a first repetition rate, a waveguide optically coupled to the pump photon source, and a photon-pair source optically coupled to the first waveguide. The system also includes a photodetector optically coupled to the photon-pair source and configured to generate a plurality of electrical pulses in response to detection of at least a portion of the plurality of pump photon pulses at the first repetition rate and a clock generator coupled to the photodetector and configured to convert the plurality of electrical pulses into a plurality of clock signals at the first repetition rate.

A system and method. The system may include a head-up display (HUD). The HUD may include a positionable combiner optical element (COE) and a combiner alignment detector (CAD) configured to conform images displayed on the positionable COE with a view through the positionable COE. The CAD may include a mirror that moves with the positionable COE, an infrared (IR) emitter configured to emit IR pulses onto the mirror with a duty cycle of less than 1% such that an average time-based radiance of the IR pulses is compatible with a night vision imaging system (NVIS), and an IR detector configured to receive the IR pulses reflected off of the mirror.

A PIC has first, second and third elements fabricated on a common substrate. The first element includes a structure supporting efficient coupling of one or more free-space optical modes of incident light into one or more waveguide guided optical modes. The second element includes an on-chip interferometer having an input optically coupled to the waveguide guided optical modes; one or more arms; one or more outputs; and a phase tuner configured to change optical path length in one or more of the arms. The third element includes one or more light detecting structures optically coupled to the one or more outputs of the second element, such that variation in optical power in the one or more outputs is detected, allowing an assessment of coherence characterizing the light incident on the first element of the PIC to be provided.