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:
A computing device and a method detect a lightness of a lighting device. The computing device captures an image of the lighting device and parses the image to obtain a pixel gray value of each lighting dot of the lighting device. The computing device obtains detection information of the lighting device according to the pixel gray value of each lighting dot of the lighting device. The computing device generates a detection report of the lighting device according to the detection information of the lighting device.
Abstract:
Disclosed is a method for testing a light-emitting device comprising the steps of: providing a light-emitting device comprising a plurality of light-emitting diodes; driving the plurality of the light-emitting diodes with a current; generating an image of the light-emitting device; and determining a luminous intensity of each of the light-emitting diodes; wherein the magnitude of the current is determined such that the current density driving each of the light-emitting diodes is smaller than or equal to 300 mA/mm2.
Abstract:
An illumination device described herein includes at least a phosphor converted LED, which is configured for emitting illumination for the illumination device, a first photodetector and a second photodetector. A spectrum of the illumination emitted from the phosphor converted LED comprises a first portion having a first peak emission wavelength and a second portion having a second peak emission wavelength, which differs from the first peak emission wavelength. The first photodetector has a detection range, which is configured for detecting only the first portion of the spectrum emitted by the phosphor converted LED. The second photodetector has a detection range, which is configured for detecting only the second portion of the spectrum emitted by the phosphor converted LED. Methods are provided herein for calibrating and controlling each portion of the phosphor converted LED spectrum, as if the phosphor converted LED were two separate LEDs.
Abstract:
Disclosed is a method of generating a correction function for a light-emitting diode (LED) testing process. The method comprises the steps of: detecting light emitted by a reference LED and reflected from one or more inactive LEDs on a panel within a field of view of a detector, a number of said inactive LEDs within the field of view being varied such that uncorrected values of at least one optical parameter are derivable as a function of the number of inactive LEDs in the field of view; detecting light emitted by the reference LED, or by an active LED having identical optical properties to the reference LED, in the absence of any other LEDs, to determine at least one reference value for the or each said optical parameter; and calculating differences between the uncorrected values and the or each reference value to generate the correction function, the correction function being based on the number of inactive LEDs which are arranged within the field of view of the detector when the detector detects light emitted by an LED under test.
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:
A system of LED-based lights comprises first and second LED-based light having respective first and second electrical connectors configured for engagement with first and second conventional fluorescent fixtures, first and second LEDs configured to produce light in an area when the first and second electrical connectors are engaged with the first and second fixtures and first and second controllers electrically coupled to the first and second LEDs; and one or more sensors operable to detect a brightness level in the area and output respectively one or more signals indicative of the brightness level, wherein: the first and second controllers are configured to control an amount of power provided to the respective first and second LEDs at least partially based on a signal to adjust the light produced in the area towards a desired brightness level.
Abstract:
A method of manufacturing a white light emitting device includes dividing a phosphor sheet into phosphor film units to be applied to individual light emitting diode (LED) devices, measuring light conversion characteristics of the respective phosphor film units, classifying the phosphor film units of the phosphor sheet into a plurality of groups according to measurement results of the light conversion characteristics and combining the phosphor film units classified into the plurality of groups and an LED device having predetermined light characteristics so as to obtain target color characteristics.
Abstract:
A novel standard light source with a more simplified construction, which is suitable for measurement of total luminous flux of a light source different in luminous intensity distribution characteristics from a conventional standard light source, and a measurement method with the use of that standard light source are provided. A standard light source includes a light emitting portion, a power feed portion electrically connected to the light emitting portion, and a restriction portion provided between the light emitting portion and the power feed portion, for restricting propagation of light radiated from the light emitting portion toward the power feed portion. A surface of the restriction portion on which light from the light emitting portion is incident is constructed for diffuse reflection.
Abstract:
Disclosed is a method for testing a light-emitting device comprising the steps of: providing a light-emitting device comprising a plurality of light-emitting diodes; driving the plurality of the light-emitting diodes with current; generating an image of the light-emitting device; and determining a luminous intensity of each of the light-emitting diodes with the image. An apparatus for testing a light-emitting device comprising a plurality of light-emitting diodes is also disclosed. The apparatus comprises: a current source to provide a current to drive the plurality of the light-emitting diodes; an image receiving device for receiving an image of the light-emitting device in the driven state; and a processing unit for determining a luminous intensity of each of the light-emitting diodes with the image.