摘要:
A light source and method for controlling the same. The light source utilizes a light generator that generates a light signal of a wavelength at an intensity that is set by a control signal. The control signal is controlled by a servo that monitors the light output of the light generator and compares the monitored value with a target value. When the target value is changed, the control signal is initially replaced by a predicted control signal based on the new target value rather than the error signal generated in the servo. This provides time for the servo to adjust to the new target value. In one embodiment, the control signal includes a periodic signal that switches between a value that causes the light generator to generate light of the wavelength and a second value at which the light generator does not generate light of the wavelength.
摘要:
A technique for controlling a Light Emitting Diode (LED) based light system involves driving individual light sources that make up the LED-based light system at non-overlapping intervals so that light source-specific feedback signals can be generated in response to the emitted light. The light source-specific feedback signals are then used to individually adjust the light sources to achieve desired luminance and chrominance characteristics of the emitted light.
摘要:
The present invention includes a light source having N light generators, a receiver, and an interface circuit. Each light generator emitting light of a different wavelength, the intensity of light generated by the kth generator is determined by a signal Ik coupled to that light generator. The receiver receives a color coordinate that includes N color components, Ck, for k=1 to N, wherein N is greater than 1. The interface circuit generates the Ik for k=1 to N from the received color components and a plurality of calibration parameters. The calibration parameters depend on manufacturing variations in the light generators. The calibration parameters have values chosen such that a light signal generated by combining the light emitted from each of the light generators is less dependent on the manufacturing variations in the light generators than a light signal generated when Ik is proportional to Ck for k=1 to N.
摘要:
A system and method for emitting and detecting light uses a light emitting device, e.g., a light emitting diode, to emit light and to detect incident light. As an example, the system and method may be used in a digital camera, a camera phone or an illuminated device, such as a liquid crystal display device.
摘要:
A color management system for a field sequential lighting system. The color management system includes a plurality of light sources, a driver circuit, and a controller. The driver circuit is coupled to the plurality of light sources, and the controller is coupled to the driver circuit. The driver circuit drives the plurality of light sources. The controller generates first and second control signals for a first subframe of a temporal sequence of subframes. The first control signal corresponds to a first light source of a first color which is a primary color for the first subframe. The second control signal corresponds to a second light source of a second color which is a supplemental color for the first subframe. Embodiments of the color management system maintain a color point of the primary color of each subframe.
摘要:
Systems and methods for illumination and color management in a system having a plurality of color sources and a plurality of color sensors, wherein there are more color sources than color sensors are described herein. An embodiment of the method includes emitting a plurality of different colors of light from at least two of the color sources, wherein the plurality of colors consist of different intensities of light emitted by the plurality of color sources. Colors of light emitted by the at least two color sources are detected using at least one of the color sensors. The color rendering index for each of the plurality of colors emitted is determined. A color of light to be emitted by the light sources is selected. The intensities of light to be emitted by the color sources is selected, based at least in part on the color rendering index, to achieve the selected color of light.
摘要:
A system and method for generating white light involves using a combination of phosphor-converted white LEDs and non-phosphor-converted color LEDs to produce white light and adjusting the emitted light in response to feedback signals. Generating white light using a combination of phosphor-converted white LEDs and non-phosphor-converted color LEDs produces white light with an improved CRI and a wide SPD. Adjusting the emitted light in response to feedback allows luminance and chrominance characteristics of the white light to be controlled as the performance of the LEDs changes over time. The emitted light can be adjusted on a per-color basis and/or on a per-group basis, where a group of LEDs includes a combination of at least one phosphor-converted white LED and at least one non-phosphor-converted color LED.
摘要:
Systems and methods for illumination and color management in a system having a plurality of color sources and a plurality of color sensors, wherein there are more color sources than color sensors are described herein. An embodiment of the method includes emitting a plurality of different colors of light from at least two of the color sources, wherein the plurality of colors consist of different intensities of light emitted by the plurality of color sources. Colors of light emitted by the at least two color sources are detected using at least one of the color sensors. The color rendering index for each of the plurality of colors emitted is determined. A color of light to be emitted by the light sources is selected. The intensities of light to be emitted by the color sources is selected, based at least in part on the color rendering index, to achieve the selected color of light.
摘要:
An apparatus and method thereof for regulating a light source are described. The apparatus includes a light-to-frequency converter that converts light received from the light source into a signal having a corresponding frequency. A circuit coupled to the light-to-frequency converter uses the frequency to regulate light that is emitted from the light source.
摘要:
A system and method for generating white light involves using a combination of white, red, green, and blue LEDs to produce white light and adjusting the emitted light in response to feedback signals. A light system has a light source that includes at least one white LED and multiple color LEDs and a spectral feedback control system configured to detect light that is output from the light source and to adjust the light that is output from the light source in response to the light detection. The spectral feedback control system may include a color sensor configured to provide color-specific feedback signals, a controller configured to generate color-specific control signals in response to the color-specific feedback signals, and a driver configured to generate color-specific drive signals in response to the color-specific control signals.