Abstract:
Optoelectronic devices that use very thin single-crystalline inorganic semiconductor films as phonon-absorbing layers in combination with non-lattice optical cavities are provided.
Abstract:
An optical system comprising a randomizer that has a plurality of randomly positioned scatterers for scattering and thereby randomizing light to generate a speckle pattern and a detector for detecting the speckle pattern to determine at least one property of the light and/or change in at least one property of the light.
Abstract:
An optical system comprising a randomizer that has a plurality of randomly positioned scatterers for scattering and thereby randomizing light to generate a speckle pattern and a detector for detecting the speckle pattern to determine at least one property of the light and/or change in at least one property of the light.
Abstract:
A photoreceiver device includes a light detector connected between a power supply node and a first node, and first to third switching elements. The light detector is configured to detect an incident optical data signal, and to output photocurrent corresponding to a magnitude of the optical data signal through the first node. The first switching element is connected between the first node and a ground node. The second switching element is connected between the power supply node and a second node. The third switching element is connected between the second node and the ground node. The third switching element has a control node connected to the first node.
Abstract:
A reference light source device for calibration of a spectral radiance meter includes an integrating sphere having a radiance reference plane, which is an opening; and a plurality of first optical ports, which are formed apart from each other in an outer wall of the integrating sphere to allow light rays with equivalent wavelength characteristics to enter an interior of the integrating sphere.
Abstract:
The invention features devices and methods for collecting and measuring light from external light sources. In general, the devices of the invention feature a light diffusing element, e.g., as a component of a light collector, connected by a light conducting conduit, e.g., a fiber optic cable, to a light measuring device, e.g., a spectrometer. This light diffusing element allows, e.g., for substantially uniform light diffusion across its surface and thus accurate measurements, while permitting the total footprint of the device to remain relatively small and portable. This light diffusing element also allows flexibility in scaling of the device to permit use in a wide range of applications.
Abstract:
A method, system, or apparatus for evaluating and/or improving illumination of a wide area target area or space above the same. Illumination of the area or space is evaluated relative to conventional illumination levels and spectral features. At least a portion of illumination is adjusted in some aspect of spectral profile to improve contrast between a target in the space or aspects of the target area or space. The adjusted illumination can be uplight, downlight, or both. Optionally, an object is launched to a known height above a lighting location, and the luminance from the object is read by a calibrated sensor, enabling verification of adequate uplighting.
Abstract:
An optical characteristic measuring apparatus includes a hemispheric portion having a reflective surface on its inner wall, and a plane portion arranged to close an opening of the hemispheric portion and having a reflective surface on an inner-wall side of the hemispheric portion. The plane portion includes a first window occupying a range including a substantial center of curvature of the hemispheric portion for attaching a light source to the first window. At least one of the hemispheric portion and the plane portion includes a plurality of second windows arranged in accordance with a predetermined rule for extracting light from inside the hemispheric portion.
Abstract:
An optical characteristic measuring apparatus includes a hemispheric portion having a reflective surface on its inner wall, and a plane portion arranged to close an opening of the hemispheric portion and having a reflective surface on an inner-wall side of the hemispheric portion. The plane portion includes a first window occupying a range including a substantial center of curvature of the hemispheric portion for attaching a light source to the first window. At least one of the hemispheric portion and the plane portion includes a plurality of second windows arranged in accordance with a predetermined rule for extracting light from inside the hemispheric portion.
Abstract:
Disclosed is a method for testing a light-emitting device comprising the steps of: providing an integrating sphere comprising an inlet port and a first exit port; disposing the light-emitting device close to the inlet port of the integrating sphere; providing a current source to drive the light-emitting device to form an image of the light-emitting device in driven state; providing an image receiving device and to receive the image of the light-emitting device, wherein the image receiving device is connected to the first exit port of the integrating sphere; and determining a luminous intensity of the light-emitting device according to the image. An apparatus for testing a light-emitting device is also disclosed. The apparatus for testing a light-emitting device comprises: an integrating sphere comprising an inlet port and a first exit port, wherein the light-emitting device is disposed close to the inlet port of the integrating sphere; an image receiving device connected to the first exit port of the integrating sphere for receiving an image of the light-emitting device; and a processing unit coupled to image receiving device for determining a luminous intensity of the light-emitting device.