Abstract:
A light sensing device includes a substrate, a plurality of light sensing elements and a cover. The plurality of light sensing elements are disposed on the substrate for sensing light. The cover is utilized for sheltering the plurality of light sensing elements, wherein the cover includes a hole for passing the light. A set of the plurality of light sensing elements is selected to be enabled according to a location of the hole relative to the plurality of light sensing elements.
Abstract:
There are provided a drift calculation device capable of accurately calculating a drift by using a buffer of smaller capacity, and a light detection device provided with the same. Every time measurement intensity is input according to a predetermined cycle, data in a plurality of sum buffers 321 to 324 are updated based on at least one of the measurement intensity and the measurement time at that time. The sum buffers 321 to 324 are assigned respectively to a plurality of sum functions forming a coefficient included in a calculation formula for calculating a drift by using the least squares method. A drift is calculated by substituting the updated data in the plurality of sum buffers 321 to 324 in the calculation formula. Since it is not necessary to store all the measurement intensity input at the predetermined cycle, a drift is accurately calculated by a buffer of smaller capacity.
Abstract:
The invention relates to a light sensing device for sensing ambient light intensity, comprising at least one ambient light sensor and an occlusion detector for detecting an object occluding the ambient light sensor. The invention is further related to a corresponding method for sensing ambient light intensity.
Abstract:
A device and method for subaperture stray light detection and diagnosis. A test light beam is generated. Stray light is detected. Based on the detected stray light, potential paths that light may have taken to arrive at the detection surface are determined. A testing device comprises a test light beam source whereby the cross sectional area of the test light beam is made less than the cross sectional area of the system aperture. A relative lateral positioning stage and an angular beam directing stage launch the test light beam into the aperture. A detector and a data processing system produce a data set relating the stray light to the location and directional angles of the test light beam to identify the sources of stray light. A light trap and test light beam delivery system are provided.
Abstract:
An optical power meter including a photodiode having a surface for receiving a beam of light, a thermo-electric cooler for maintaining the photodiode at a predetermined temperature, and a current monitor for measuring a drive current passing through the thermo-electric cooler allows dark current drift arising from a varying thermal gradient across the active region of the photodiode to be corrected, thus improving stability of the optical power meter. More specifically, by monitoring the TEC drive current, and applying a correction factor to the optical power readings, the stability of optical power readings is improved by an order of magnitude.
Abstract:
A wireless battery-powered daylight sensor for measuring a total light intensity in a space is operable to transmit wireless signals using a variable transmission rate that is dependent upon the total light intensity in the space. The sensor comprises a photosensitive circuit, a wireless transmitter for transmitting the wireless signals, a controller coupled to the photosensitive circuit and the wireless transmitter, and a battery for powering the photosensitive circuit, the wireless transmitter, and the controller. The photosensitive circuit is operable to generate a light intensity control signal in response to the total light intensity in the space. The controller transmits the wireless signals in response to the light intensity control signal using the variable transmission rate that is dependent upon the total light intensity in the space. The variable transmission rate may be dependent upon an amount of change of the total light intensity in the space. In addition, the variable transmission rate may be further dependent upon a rate of change of the total light intensity in the space.
Abstract:
A sensing device transmits wireless signals when an error between at least one sampled parameter value and at least one predicted parameter value is too great, such that the sensing device transmits wireless signals to a load control device using a variable transmission rate that is dependent upon the amount of change in a value of the parameter. The sensing device uses the one or more estimators to determine the predicted parameter value, and may transmit the estimators to the load control device if the error is too great. The load control device uses the estimators to determine at least one estimated parameter value and controls the electrical load in response to the estimated parameter value. The sensing device may comprise, for example, a daylight sensor for measuring a total light intensity in the space around the sensor or a temperature sensor for measuring a temperature around the sensor.
Abstract:
Electronic devices may include light sensors. A light sensor may be an ambient light sensor that is mounted adjacent to an aperture in an opaque structure. An ambient light sensor may include active light sensor elements located adjacent to the aperture and inactive light sensor elements located adjacent to the opaque structure. Signal processing circuitry may be interposed between the light sensor elements and a summing circuit that sums light signals from the light sensor elements to form an ambient light signal. The signal processing circuitry may include a switch and an amplifier associated with each light sensor element. The switch associated with each element may be used to selectively activate or inactivate that element. The amplifier associated with each element may be used to amplify the light signal from that element by a gain factor that depends on the location of that element with respect to the aperture.
Abstract:
A semiconductor device includes a pair of sensor units each of which includes a photoelectric conversion unit, a signal holding unit and a transfer unit, and outputs a signal held by the signal holding unit, comprising a control unit including a detector unit, wherein when one of the pair of sensor units operates in a first mode, the other operates in a second mode, the detector unit detects that the output has reached a predetermined value after the one starting a signal transfer, the one ends the signal transfer in response to the detection and determines the held signal, the control unit generates a control signal after that, and the other in the second mode accumulates generated charges and starts a signal transfer in accordance with the control signal, then ends the signal transfer and determines the held signal.
Abstract:
A sensor device has a display part that displays a numerical value and a character on a casing and at least three switches. The switches have an up switch and a down switch. The up switch has a function of changing the numerical value to increase and also the down switch has a function of changing the numerical value to decrease. Each switch has a different function and each switch has a different symbol.