Lighting fixture and system using free space optical communication process
A light fixture includes an array of light-emitting elements for generating light from the light fixture, and the array of light-emitting elements includes a defined sub-array of light-emitting elements. An alternate array of light-emitting elements is coupled in parallel with the defined sub-array of alternate light-emitting elements of the light emitter. Each of the sub-array and the alternate array are coupled with a respective switch element. A control circuit is coupled with the switch elements and configured for selectively switching power between the sub-array and the alternate array for modulating the operation of the sub-array and alternate array of light-emitting elements to generate modulated communication signals.
1. A light fixture comprising:
an array of light-emitting elements for generating light from the light fixture, the array of light-emitting elements including a defined sub-array of a number of light-emitting elements smaller than the number of elements in the array, the light-emitting elements of the array operable for generating visible light radiation;
an alternate array of light-emitting elements coupled electrically in parallel with the defined sub-array of light-emitting elements, the light-emitting elements of the alternate array being operable for generating non-visible radiation;
each of the sub-array and the alternate array electrically coupled with a respective switch element to individually control the sub-array and alternate array independently of the remaining elements of the array;
a control circuit coupled with the switch elements and configured for selectively switching power between the sub-array and the alternate array for modulating the operation of the sub-array and the non-visible radiation elements of the alternate array of light-emitting elements to generate modulated communication signals with the alternate array of light-emitting elements while the remaining elements of the array continue to operate.
2. The light fixture of claim 1 wherein the non-visible radiation includes at least one of infrared (IR) radiation and ultraviolet (UV) radiation.
3. The light fixture of claim 1 wherein the array of light-emitting elements includes at least one LED element.
4. The light fixture of claim 1 wherein the sub-array of light-emitting elements includes at least one LED element.
5. The light fixture of claim 1 wherein the alternate array of light-emitting elements includes at least one LED element.
6. The light fixture of claim 1 wherein elements in the sub-array and alternate array are electrically connected in series in the respective arrays.
7. The light fixture of claim 1 wherein elements in the sub-array are electrically connected in series in the sub-array and elements in the alternate array are electrically connected in parallel in the alternate array.
8. The light fixture of claim 1 wherein at least one of the switch elements includes a transistor.
9. The light fixture of claim 1 wherein the control circuit includes at least one data line for providing a modulation signal for the control circuit for control of the modulated communication signals.
10. The light fixture of claim 1 wherein the control circuit includes an opto-isolator circuit for control of the switch elements.
11. The light fixture of claim 1 wherein the number of light-emitting elements in the sub-array is different than the number of light-emitting elements in the alternate array.
12. The light fixture of claim 1 wherein the number of light-emitting elements in the sub-array is less than the number of light-emitting elements in the alternate array.
13. The light fixture of claim 1 wherein the number of light-emitting elements in the sub-array is greater than the number of light-emitting elements in the alternate array.
14. The light fixture of claim 1 wherein the number of light-emitting elements in the sub-array is equal to the number of light-emitting elements in the alternate array.