Abstract:
Embodiments as disclosed herein provide a method and system that characterizes physical properties, such as thickness, uniformity, polarization, and/or sizes and locations of defect (e.g. defect density distribution) of crystalline structures grown on or thin films deposited on a substrate of a solid state light emitting device. The embodiments disclosed herein generally include exciting the light emitting device with an energy source and analyze optical energy emitted by the crystalline structures grown on or the thin films deposited on the substrate.
Abstract:
Methods and apparatus (100) for profiling a beam of a light emitting semiconductor device. The apparatus comprises a light emitting semiconductor device (102) comprising an active region (108) formed on a substrate (104) and configured to generate light when a suitable electrical current is applied to contacts on an upper surface of the device and a light emitting surface (110) defined by a lower surface of the substrate opposite the contacts. The apparatus further comprises a transmission medium (112) comprising a first surface (114) in contact with at least part of the light emitting surface of the semiconductor device and a diffusion surface (116), opposite the first surface, and configured to diffuse light emitted from the micro-LED and transmitted through the transmission medium.
Abstract:
An optical sensor circuit comprises an optical sensor (DET) designed to provide a sensor signal indicative of a color of light incident on the optical sensor (DET), a clock designed to provide a clocked control signal comprising consecutive high and low states, and a controller unit (CU) connected to the optical sensor (DET) and comprising the clock. The controller unit (CU) is designed to process the sensor signal as a color signal (CTS) in a first mode if the clocked control signal is in a high state, wherein the color signal (CTS) is indicative of a color of light emitted by a light emitting device (LED) to be connected at a control terminal (OUT). The controller unit (CU is further designed to process the sensor signal as an ambient color light signal (aCTS) in a second mode if the clocked control signal is in a low state, wherein the ambient color light signal (aCTS) is indicative of a color of ambient light. The controller unit (CU) is also designed to generate a driving signal (PWM) to drive the light emitting device (LED), wherein the driving signal (PWM) depends on the color and ambient color light signals (CTS, aCTS).
Abstract:
The present application discloses a LED-based solar simulator light source having at least one LED array formed by multiple LED groups of LED assemblies, at least one field flattening device, at least one diffractive element, and at least one optical element configured to condition the broad spectrum light source output signal and direct the light source output signal to a work surface.
Abstract:
Embodiments provide a method of evaluating luminance of a light source, including acquiring first data including a plurality of luminance values by measuring luminance of the light source, converting the first data into second data corresponding to a plurality of unit cells, acquiring a moving average of the second data, and acquiring a ripple factor. The ripple factor is represented by (Draw−Ma)/Ma, where Draw is the second data and Ma is the moving average.
Abstract:
Systems and methods for accurately measuring the luminous flux and color (spectra) from light-emitting devices are disclosed. An integrating sphere may be utilized to directly receive a first portion of light emitted by a light-emitting device through an opening defined on the integrating sphere. A light collector may be utilized to collect a second portion of light emitted by the light-emitting device and direct the second portion of light into the integrating sphere through the opening defined on the integrating sphere. A spectrometer may be utilized to measure at least one property of the first portion and the second portion of light received by the integrating sphere.
Abstract:
An illumination device comprises one or more emitter modules having improved thermal and electrical characteristics. According to one embodiment, each emitter module comprises a plurality of light emitting diodes (LEDs) configured for producing illumination for the illumination device, one or more photodetectors configured for detecting the illumination produced by the plurality of LEDs, a substrate upon which the plurality of LEDs and the one or more photodetectors are mounted, wherein the substrate is configured to provide a relatively high thermal impedance in the lateral direction, and a relatively low thermal impedance in the vertical direction, and a primary optics structure coupled to the substrate for encapsulating the plurality of LEDs and the one or more photodetectors within the primary optics structure.
Abstract:
An LED-based light includes one or more LEDs, a sensor arranged to detect a brightness level in an area resulting from the combination of light emitted by the LEDs with light from at least one ambient light source other than the LEDs, and operable to output a signal corresponding to the detected brightness level, a controller operable to regulate an amount of power provided to the LEDs in response to the signal, a light transmitting housing for the LEDs, the sensor and the controller and a connector shaped for connection with a light socket disposed at an end of the housing.
Abstract:
An LED-based light tube for use in a conventional fluorescent fixture includes a housing including a light transmitting portion, at least one electrical connector attached to the housing and configured for engagement with the conventional fluorescent fixture, at least one LED arranged to produce light in a direction toward the light transmitting portion, a sensor operable to detect a brightness level and output a signal corresponding to the detected brightness level, and a controller in electrical communication with the at least one electrical connector, operable to: compare the signal to a predetermined value corresponding to a desired brightness level and control an amount of power provided to the at least one LED in response to the signal to adjust the light produced by the at least one LED to achieve the desired brightness level.
Abstract:
The present invention relates to a total luminous flux measurement system and a method thereof for measuring a total luminous flux of a light emitting component. The total luminous flux measurement system includes a light receiving module, a first light detector and a processing module. The light receiving module is disposed on a central normal of the light emitting component and divides a projection light field to a forward light field and a side light field. The light receiving module receives a beam in the forward light field to obtain a forward luminous flux. The first light detector is disposed on a side of the light receiving module to receive a beam in the side light field to obtain a first side luminous flux. The processing module electrically connects the light receiving module and the first light detector to calculate the total luminous flux at the light emitting component.