In one respect, disclosed is a device or system for solar irradiance measurement comprising at least two irradiance sensors deployed outdoors at substantially different angles, such that, by analysis of readings from said irradiance sensors, direct irradiance, diffuse irradiance, and/or global irradiance are determined. In another respect, the disclosed device or system may additionally determine ground-reflected irradiance.

Example embodiments described herein involve a system for testing a light-emitting module. The light-emitting module may include a mounting platform configured to hold a light-emitting module for a camera. The mounting platform may also be configured to rotate. The system may further include a housing holding a plurality of photodiodes arranged in an array over at least a 90 degree arc of a hemisphere. The system may also include a controller configured to control the photodiodes and the rotation of the mounting platform.

An optical receiver (100) for detection of light from one or more sources (108) comprises an opaque layer (102) disposed on a first surface. An aperture (104) is formed in the opaque layer. An optical detector (106) has a detection region disposed on a second surface. The first and second surfaces are spaced apart from one another such that light passing through the aperture (104) illuminates a corresponding illumination region (110) on the second surface, and is detected by the optical detector (106) In the event that the detection region overlaps the illumination region. Multiple apertures may be formed in the opaque layer, and/or multiple optical detectors may be disposed on the second surface. The optical receiver may thereby enable optical signals originating at different locations to be detected, and distinguished, over a wide field of view.

A sky luminance mapping system includes a camera unit, two pyranometer units and a processing unit. Camera unit includes a fisheye lens to shoot image of sky dome and is equipped with light-shading devices which block the sun from the camera unit corresponding to instant location of the sun at instant time. First pyranometer unit measures daylight illuminance from the sky dome and outputs first intensity signal while the light-shading device is applied to block the sun. Second pyranometer unit measures daylight illuminance from the sky dome and outputs second intensity signal without blocking the sun. A reference intensity value is obtained by subtracting a value of the first intensity signal from a value of the second intensity signal. According to the value of the first intensity signal and the reference intensity value, a total luminance of and the luminance distribution in the image of the sky dome are corrected.

Certain aspects pertain to a combination sensor comprising a set of physical sensors facing different directions proximate a structure, and configured to measure solar radiation in different directions. The combination sensor also comprises a virtual facade-aligned sensor configured to determine a combi-sensor value at a facade of the structure based on solar radiation readings from the set of physical sensors.

A method and associated apparatus are disclosed for measuring illumination characteristics of a luminaire having unknown characteristics. The method includes steps of providing an array of calibrated photodetectors in known locations in proximity to a mounting location, and then illuminating the array with a luminaire having unknown illumination properties. The resulting data is used to calculate the luminous intensity vs. angle from the luminaire and the luminous flux of the luminaire. Methods of calibrating the measurement with a known luminaire are presented along with methods of determining the angular position of the detectors in the array. Color-sensitive detectors can be used to determine the angular distribution and average value of the luminaire's correlated color temperature.

An electronic device may be provided with a display mounted in a housing. A directional ambient light sensor may measure the intensity and direction of ambient light. The ambient light sensor may be mounted in alignment with a light sensor window formed in an inactive area of the display. The ambient light sensor may be formed from detectors on a semiconductor substrate. Incident light angle restriction structures may define openings for each detector. Each opening may be configured to allow light with a different range of angle of incidence values to be passed to a respective one of the detectors. The ranges of acceptance angle for adjacent detectors may overlap. A sensor may produce a diffuse light reading by processing ambient light data from a diffuse light detector and a directional light detector. The diffuse and directional light detectors may be formed on a common semiconductor substrate.

The optical device for measuring at least one of reflected light (BRDF) and transmitted light (BTDF) from a sample, in all spherical directions of space around the sample, for each spherical direction of incident light includes a light source, and a goniophotometer configured to measure at least one of: directions of the incident light in spherical coordinates, and directions of the reflected light in spherical coordinates. The device further includes a dispersive screen, and a multi-sensor imaging device. The goniophotometer includes a first articulated arm supporting the light source; and a second articulated arm supporting the sample or a sample holder.

Methods and apparatus for determining an intensity profile of a radiation beam. The method comprises providing a diffraction structure, causing a relative movement of the diffraction structure relative to the radiation beam from a first position, wherein the radiation beam does not irradiate the diffraction structure to a second position, wherein the radiation beam irradiates the diffraction structure, measuring, with a radiation detector, diffracted radiation signals produced from a diffraction of the radiation beam by the diffraction structure as the diffraction structure transitions from the first position to the second position or vice versa, and determining an intensity profile of the radiation beam based on the measured diffracted radiation signals.

Certain aspects pertain to a combination sensor comprising a set of physical sensors facing different directions proximate a structure, and configured to measure solar radiation in different directions. The combination sensor also comprises a virtual facade-aligned sensor configured to determine a combi-sensor value at a facade of the structure based on solar radiation readings from the set of physical sensors.