An optical liquid height determination system of the present embodiments includes light sensors capturing different amounts of light, based on level of liquid in the tank that blocks or limits light to particular sensors. The tank is enclosed in a container with a light source and the light sensors are installed on walls of the container. Light emitted by the light source is transmitted to the light sensors by passing through the liquid product, scattered, diffused, diffracted or reflected by the dairy product, through the tank walls which may be transparent or translucent, or from other surfaces in the container within which the tank is enclosed by. The set of electrical signals received from all the light sensors are compared against sets of calibrated signals corresponding to known liquid levels in the tank. The known height corresponding to the nearest set of calibrated signals is determined as the measured liquid height in the tank.

In one example, an apparatus comprises: a photodiode configured to generate charge in response to incident light within an exposure period; and a quantizer configured to perform at least one of a first quantization operation to generate a first digital output or a second quantization to generate a second digital output, and output, based on a range of an intensity of the incident light, one of the first digital output or the second digital output to represent the intensity of the incident light. The first quantization operation comprises quantizing at least a first part of the charge during the exposure period to generate the first digital output. The second quantization operation comprises quantizing at least a second part of the charge after the exposure period to generate the second digital output.

A method, device, and display device for detecting ambient light are provided. The method includes obtaining brightness information of the ambient light, determining a brightness interval of the ambient light according to the brightness information of the ambient light and preset correspondences between a plurality of ambient light sensors and different brightness intervals, using the ambient light sensor corresponding to the brightness interval of the ambient light as a reference sensor, and outputting a brightness signal of a current ambient light according to output signals of the ambient light sensors and a preset conversion formula.

Provided are an apparatus and method for measuring quantum efficiency of a detector using a single pulse laser. Quantum efficiency of the measurement target detector may be measured from 420 nm to 1600 nm having uncertainty of 2% to 4% (K=2) by comparing the reference detector and the measurement target detector significantly different in sensitivity using a single laser pulse as a spectral light source. Also, it is possible to directly compare the two detectors with a significant difference in sensitivity through a very simple setup that causes a portion of a laser pulse output from a light source part to be absorbed by the reference detector and the laser pulse reflected from the reference detector to be irradiated to the measurement target detector.

A solar spectrum sensor, a consumer device and a method for determining an ambient solar spectrum. The solar spectrum sensor comprises a sensor unit configured for generating respective photo current outputs responsive to different parts of the solar spectrum; a measurement unit configured for measuring the respective photo current outputs from the sensor unit; and a processing unit for determining an average photon energy, APE, value of the solar spectrum from the measured photo current outputs and for determining the solar spectrum based on the determined APE.

An embodiment of a method for compensating variations in an attenuation of light of an optical filter of a light sensor system comprises illuminating a clear sensor and a color sensor of the light sensor system with a test light having a test spectrum. Therein the color sensor comprises the optical filter and is designed to predominantly sense light with a wavelength within a pass band of the filter; and the test spectrum has components outside the pass band. A clear test signal generated by the clear sensor and a color test signal generated by the color sensor are received in particular in response to the illumination with the test light. Then a first transmission value T is determined based on the clear test signal and on the color test signal. Finally, a compensation factor Kr, Kg, Kb is calculated to compensate the variations in the attenuation of light based on the first transmission value T and a nominal transmission value Tn of the filter.

Systems and methods are disclosed for protecting a UV-transmissive window. The system includes a first light source for emitting UV energy. The system also includes a UV transmissive window having a planar dimension and a thickness direction perpendicular to the planar dimension, the window positioned so that UV energy from the UV light source passes through the thickness dimension of the window. The system further includes a second light source for introducing a beam of light transverse to the thickness dimension of the window, a detector for detecting light received from the second light source after the light passes through the thickness dimension, and a control system responsive to changes in the detected light received from the second light source and configured to transmit an alert when a change in the detected light exceeds a threshold.

Provided are gaze tracking apparatuses, which in some embodiments can include an optoelectronic device, wherein the optoelectronic device includes an image sensor with non-local readout circuit having a substrate and a plurality of pixels and operatively connected to a control unit, wherein a first area of the substrate is at least partially transparent to visible light and at least the plurality of pixels of the image sensor are arranged on the first area of the substrate to aim to an eye of a user when placed in front of an inner face of the substrate, and wherein the control unit is also adapted to control the image sensor to acquire image information from the user's eye for performing a gaze tracking of the user's eye.

An optical parameter measurement device and a corresponding method are provided. A light beam from a to-be-tested display panel is split by a beam-splitting assembly into at least two testing light beams. A voltage value corresponding to a first testing light beam is measured by a trans-impedance amplification circuit corresponding to a first optical sensor. Next, an integration time period is determined by a control circuit according to voltage values from the trans-impedance amplification circuit and a predetermined relational model between voltage values corresponding to the light intensities and integration time periods. A voltage value corresponding to a second testing light beam is finely measured by the integration circuit corresponding to a second optical sensor within the integration time period. Finally, the display brightness value of the to-be-tested display panel is determined by the control circuit according to a voltage value from the integration circuit within the integration time period.

A method of identifying the presence of a first gas such as methane within a sample, for example containing natural gas. A detector is provided having a sensor responsive to a first wavelength, a sensor responsive to a second wavelength, and a sensor for collecting reference readings. A gas sample is analysed to obtain a first absorption reading corresponding to the first wavelength, a second absorption reading corresponding to the second wavelength and a reference reading. A first absorption figure is calculated using the first absorption reading and the reference reading, and a second absorption figure using the second absorption reading and the reference reading. The sensor for each wavelength is calibrated for detecting the first gas such that the data collected at each wavelength gives the same reading when only said first gas is present in a sample.