Rgb combiner using mems alignment and plc

Abstract

Light from discrete red, blue, and green lasers are combined into a single output using a planar lightwave circuit (PLC). In some embodiments some light from an output of the PLC is reflected back to the lasers, and in some embodiments the reflected light is primarily of one of the red, green, or blue wavelengths. In some embodiments multiple lasers of slightly differing wavelengths are provided as light sources for some or all of the red, blue, and green light.

1 . A device useful as a color display light source, comprising:
 a plurality of laser diodes, outputs of the laser diodes combinable to provide different colors in a spectrum of visible light; and   a planar lightwave circuit (PLC) configured to receive light of the laser diodes and combine at least some of the received light into an output, the planar lightwave circuit also configured to reflect some of the light about a particular wavelength in the visible spectrum back to at least one of the laser diodes.   
     
     
         2 . The device of  claim 1 , wherein a first of the laser diodes comprises a first laser diode configured to generate a red light, a second of the laser diodes comprises a second laser diode configured to generate a green light, and a third of the laser diodes comprises a third laser diode configured to generate a blue light. 
     
     
         3 . The device of  claim 2 , wherein the particular wavelength in the visible spectrum is a wavelength for red light. 
     
     
         4 . The device of  claim 3 , wherein the first of the laser diodes includes an anti-reflective coating on a front output facet. 
     
     
         5 . The device of  claim 4 , wherein the second and third of the laser diodes are at least partially reflective on their front output facets. 
     
     
         6 . The device of  claim 5 , wherein the first laser diode provide a gain medium for an external cavity laser. 
     
     
         7 . The device of  claims 3 , wherein the PLC is configured to reflect the at, least some of the light using a partly reflecting surface on an output of the PLC. 
     
     
         8 . The device of  claim 2 , further comprising a plurality of lenses positioned to couple light from the laser diodes to the PLC. 
     
     
         9 . The device of  claim 8 , wherein each of the plurality of lenses are on a respective lever that magnifies motion of the lens. 
     
     
         10 . The device of  claim 8 , wherein each lens is a ZnS lens. 
     
     
         11 .- 15 . (canceled)