Using white LEDs to enhance intensity of colored light from colored LEDs
The present disclosure describes light systems in which the intensity of base color LEDs configured to emit light within a target color region is increased using additional white LEDs and the emitted light is filtered so that a dominant portion of light passing through the filter at a particular viewing angle is within the target color region. The present disclosure also describes methods for forming a printed circuit board with an integral heat sink arrangement by depositing additional solder on solder pads that are not used to connect electronic components so that the additional solder acts as a heat sink.
1. A light system for projecting light within and limited to a non-white target color region, the light system comprising:
a confining primary optic having a focus and a viewing angle range and configured to direct light from the focus outwardly within the viewing angle range;
at least one base color light emitting diode (LED) positioned substantially on the focus, the at least one base color LED configured to emit light within the target color region;
at least one pair of additive LEDs substantially offset from the focus;
the at least one pair of additive LEDs being associated with and positioned adjacent to a respective base color LED; and
within each pair of additive LEDs, one member of the pair is disposed with its optical center on a first side of the focus and the other member of the pair is disposed with its optical center on a second side of the focus opposite the first side of the focus;
the at least one pair of additive LEDs being configured to emit light within a white color region for which a correlated color temperature (CCT) of the light within the white color region is skewed toward the target color region; and
a filter interposed between the LEDs and a notional viewer, the filter configured to suppress light outside of the target color region;
wherein a dominant portion of filtered light passing through the filter to the notional viewer at a midpoint of the viewing angle range is within the target color region.
2. The light system of claim 1 , further comprising a control circuit coupled to the at least one base color LED and the at least one additive LED for flashing the at least one base color LED and the at least one additive LED.
3. The light system of claim 1 , wherein within the at least one pair of additive LEDs:
each member of the at least one pair has identical photometric output; and
each member of the at least one pair is disposed with its optical center equidistant from the focus.
4. The light system of claim 1 , wherein the primary optic is a reflector.
5. The light system of claim 1 , wherein the primary optic is a Fresnel lens.
6. The light system of claim 5 , wherein the filter is integral with the Fresnel lens.
7. The light system of claim 1 , wherein all of the light emitted from the at least one base color LED is entirely within the target color region.
8. The light system of claim 7 , wherein all of the light emitted from the at least one additive LED is entirely within the white color region.
9. The light system of claim 1 , wherein all of the light emitted from the at least one additive LED is entirely within the white color region.