An LED light fixture, in the form of lamps or luminaires, is comprised on a plurality of LED lights producing bright white or warm light and a plurality of color LED lights producing light of a visibly different color. The fixture includes control circuitry for receiving an input voltage signal from a dimmer switch wherein when the dimmer switch reduces the input voltage to the LED light fixture within a top range setting of the dimmer switch, the brightness of the light is maintained while the color Kelvin temperature of the light spectrum is reduced. If the dimmer switch is increased in the top range, the color temperature increases. This is achieved by increasing the frequency of a reduced input voltage signal during a reduction of the dimmer switch in the top range thereof to supply full driver current to the white or warm light LED's while reducing the driver current to the color LED's. When the dimmer switch is operated below the top range both drive currents to the while and color LED's is reduced to provide a warm relaxing light spectrum but with substantially high luminosity/brightness.

An LED light fixture, in the form of lamps or luminaires, is comprised on a plurality of LED lights producing bright white or warm light and a plurality of color LED lights producing light of a visibly different color. The fixture includes control circuitry for receiving an input voltage signal from a dimmer switch wherein when the dimmer switch reduces the input voltage to the LED light fixture within a top range setting of the dimmer switch, the brightness of the light is maintained while the color Kelvin temperature of the light spectrum is reduced. If the dimmer switch is increased in the top range, the color temperature increases. This is achieved by increasing the frequency of a reduced input voltage signal during a reduction of the dimmer switch in the top range thereof to supply full driver current to the white or warm light LED's while reducing the driver current to the color LED's. When the dimmer switch is operated below the top range both drive currents to the while and color LED's is reduced to provide a warm relaxing light spectrum but with substantially high luminosity/brightness.

Apparatus and methods for controlling correlated color temperature (CCT) and lighting intensity in lighting fixtures are described. The CCT and intensity may be controlled independently over conventional AC wiring using a conventional dimmer. A lighting controller that resembles a conventional dimmer and that can be installed in place of a dimmer may be used instead of a conventional dimmer to access more control functionalities, still using conventional AC wiring. Wireless communication with the lighting fixture and/or lighting controller are possible.

The present invention relates to a lamp (1), comprising a lamp base (3), a semi-reflective envelope (2), at least one first solid state light source filament (4a-d) arranged inside the semi-reflective envelope (2), and a second solid state light source (5) arranged inside the semi-reflective envelope (2), wherein the reflectivity of the semi-reflective envelope (2) is in the range from 30% to 70% for light emitted by the at least one first solid state light source filament (4a-d) and the second solid state light source (5), wherein the at least one first solid state light source filament (4a-d) is arranged at a first distance lower than 7 millimeters from the semi-reflective envelope (2), and wherein the second solid state light source (5) is arranged at second distance higher than 15 millimeters from the semi-reflective envelope (2).

A chip-on-board type photoelectric device exemplarily includes: a package substrate, provided with a chip mounting region, a first electrode and a second electrode, the first and second electrodes being arranged spaced from each other at a periphery of the chip mounting region; first photoelectric chips, arranged in the chip mounting region to form inwardly concave strip-shaped patterns as mutually spaced first color temperature regions, and electrically connected between the first and second electrodes to form at least one first photoelectric chip string; and second photoelectric chips, arranged in the chip mounting region to form second color temperature regions. A light-emitting color temperature of each the second color temperature region is higher than that of each the first color temperature region. The second photoelectric chips are electrically connected between the first and second electrodes to form second photoelectric chip strings. A good uniformity of light mixing can be achieved.

A method of operating an LED lamp coupled with a dimmer switch and includes receiving an input signal from the dimmer switch corresponding to a setting of the dimmer switch within its dimmable range, detecting a change of the setting within the upper portion of the dimmable range, which includes 80% to 100% of a maximum setting of the dimmer switch, and, responsive to detecting the change, adjusting drive current to at least one of a first or a LED light source to change a composite CCT produced by them within a first CCT range including about 3000 Kelvin to about 5000 Kelvin while substantially maintaining a composite brightness produced by the first and second LED light sources.

A method of operating an LED lamp coupled with a dimmer switch and includes receiving an input signal from the dimmer switch corresponding to a setting of the dimmer switch within its dimmable range, detecting a change of the setting within the upper portion of the dimmable range, which includes 80% to 100% of a maximum setting of the dimmer switch, and, responsive to detecting the change, adjusting drive current to at least one of a first or a LED light source to change a composite CCT produced by them within a first CCT range including about 3000 Kelvin to about 5000 Kelvin while substantially maintaining a composite brightness produced by the first and second LED light sources.

Systems, methods, and devices described herein provide for operating a lighting fixture with a plurality of light sources at a target chromaticity with a target output spectral power distribution. The methods include multiplying a first spectral power distribution by a second spectral power distribution to determine a product spectral power distribution, multiplying the product spectral power distribution by an illuminant spectral power distribution to determine the target output spectral power distribution at the target chromaticity, and driving the plurality of light sources at intensities corresponding to the target output spectral power distribution.

Systems, methods, and devices described herein provide for operating a lighting fixture with a plurality of light sources at a target chromaticity with a target output spectral power distribution. The methods include multiplying a first spectral power distribution by a second spectral power distribution to determine a product spectral power distribution, multiplying the product spectral power distribution by an illuminant spectral power distribution to determine the target output spectral power distribution at the target chromaticity, and driving the plurality of light sources at intensities corresponding to the target output spectral power distribution.

Light emitting diode (LED) lighting fixtures are presented that use a low-pass filter to smooth out or eliminate discrete, step changes in LED light fixture brightness, that may result from the use of digital brightness level settings. Because some lighting applications require a fast response to changes in the set brightness level, and some applications require a slower response, one set of examples use a switchable RC low-pass filter circuit, with two or more selectable RC time constant values. Another set of examples use a programmable resistance integrated circuit to achieve a more continuously-variable time constant, for greater flexibility in adjusting the response time of the LED lighting fixture, in response to user brightness inputs. The user is able to control the maximum rate of change of the LED light fixture's brightness, in response to changes in the brightness setting.