Integrated optical system for dynamic diffuse and directional lighting
An illumination system can produce a dynamically variable illumination pattern. The illumination system can include a light guide. The illumination system can include projection optics, which can contribute to the illumination pattern at relatively low beam angles (i.e., beam angles formed with respect to a surface normal of the light guide). The projection optics can include individually addressable light-producing elements that can direct light through one or more focusing elements. A controller can control which of the light-producing elements are electrically powered and can therefore control the illumination pattern contribution from the projection optics. The illumination system can also include scattering optics, which can contribute to the illumination pattern at relatively high beam angles. The scattering optics can direct light out of the light guide over a relatively large surface area, which can help reduce glare when the light guide is viewed directly.
1. An illumination system, comprising:
a light guide having a first surface and a second surface opposite the first surface;
a light-emitting diode (LED) array configured to direct first light into the light guide through the first surface of the light guide;
focusing optics configured to collimate the first light to emerge from the light guide through the second surface of the light guide as collimated projected light; and
an LED spaced apart from the LED array and configured to direct second light into the light guide as guided light that is guided between the first surface and the second surface.
2. The illumination system of claim 1 , wherein the focusing optics is located external to the light guide or at the first surface of the light guide.
3. The illumination system of claim 1 , further comprising a plurality of light-extraction features configured to direct at least some of the guided light out of the light guide through the second surface of the light guide as scattered light.
4. The illumination system of claim 3 , wherein the first light does not interact with the plurality of light-extraction features.
5. The illumination system of claim 3 , wherein the plurality of light-extraction features are disposed on the second surface of the light guide.
6. The illumination system of claim 1 , further comprising a controller configured to:
electrically control the LED array;
electrically power one of a plurality of specified subsets of LEDs of the LED array, and
receive input that specifies which of the plurality of specified subsets is to be electrically powered.
7. The illumination system of claim 1 , wherein:
the LED array includes a first LED; and
the focusing optics includes a first lens positioned in a first optical path between the first LED and the first surface of the light guide.
8. The illumination system of claim 7 , wherein:
the illumination system further comprises a second LED positioned away from the first LED, the first LED and the second LED being located on separate substrates; and
the focusing optics includes a second lens positioned in a second optical path between the second LED and the first surface of the light guide, the second optical path being non-overlapping with the first optical path.
9. The illumination system of claim 1 , wherein:
the LED array includes a first LED; and
the focusing optics includes a first curved portion disposed on the first surface of the light guide and a second curved portion disposed on the second surface of the light guide, the first and second curved portions configured to collimate light emitted from the first LED.
10. The illumination system of claim 9 , wherein:
the illumination system further comprises a second LED positioned away from the LED array; and
the focusing optics includes a third curved portion disposed on the first surface of the light guide and a fourth curved portion disposed on the second surface of the light guide, the third and fourth curved portions configured to collimate light emitted from the second LED.
11. The illumination system of claim 1 , wherein the LED is spaced apart from the LED array and configured to direct the second light into an edge of the light guide, the edge extending between the first and second surfaces of the light guide.
12. The illumination system of claim 1 , wherein the LED array includes at least two LEDs that emit light having different correlated color temperatures.
13. The illumination system of claim 1 , further comprising a first LED configured to direct third light into the light guide as guided light that is guided between the first surface and the second surface, the second light and the third light having different correlated color temperatures.
14. A method for providing illumination, the method comprising:
producing first light with a light-emitting diode (LED) array;
directing the first light into a light guide through a first surface of the light guide;
collimating the first light, with focusing optics, to emerge from the light guide through a second surface of the light guide as collimated projected light, the second surface of the light guide being opposite the first surface of the light guide;
producing second light with an LED that is spaced apart from the LED array;
directing the second light into the light guide as guided light that is guided between the first surface and the second surface; and
directing, with a plurality of light-extraction features, at least some of the guided light out of the light guide through the second surface of the light guide as scattered light.
15. The method of claim 14 , further comprising:
receiving input that specifies a first subset of a plurality of specified subsets of LEDs of the LED array; and
electrically powering the first subset of the plurality of specified subsets of LEDs of the LED array.
16. An illumination system, comprising:
a light guide having a first surface and a second surface opposite the first surface, the light guide defining a hole extending through the light guide from the first surface to the second surface;
a light-emitting diode (LED) array configured to emit first light;
focusing optics configured to at least partially focus the first light and direct the first light through the hole in the light guide to emerge from the hole at the second surface of the light guide as projected light; and
an LED spaced apart from the LED array and configured to direct second light into the light guide as guided light that is guided between the first surface and the second surface.
17. The illumination system of claim 16 , wherein the focusing optics is located external to the light guide, such that the at least partially focused first light enters the hole at the first surface of the light guide.
18. The illumination system of claim 16 , wherein the hole is substantially cylindrical.
19. The illumination system of claim 16 , wherein the hole extends along a hole axis that is substantially orthogonal to the second surface of the light guide.
20. The illumination system of claim 16 , further comprising a plurality of light-extraction features configured to direct at least some of the guided light out of the light guide through the second surface of the light guide as scattered light.