Multiple-laser light source

Abstract

A light source includes a plurality of laser diodes or other light emitters. Beams of light from the light emitters are steered to provide n array of parallel beams that illuminate a target area with an array of patches of light. In some embodiments the parallel beams are de-magnified to form the array of patches of light. Such a light source has application in illuminating dynamically-addressable focusing elements such as phase modulators, deformable mirrors and dynamically addressable lenses. Light projectors for a wide variety of applications may combine a light source as described herein with a dynamically-addressable focusing element to project defined patterns of light.

1 . A light source comprising:
 a plurality of light emitters, each of the light emitters operable to emit a corresponding beam of light;   one or more mirrors arranged to redirect the beams of light to provide a closely-spaced array of parallel light beams; and   a dynamically-addressable focusing element illuminated by the closely-spaced array of parallel light beams the dynamically-addressable focusing element having an active area substantially covered by an array of patches of light, each of the patches of light corresponding to one of the light beams in the closely-spaced array of parallel light beams;   wherein the mirrors include at least one mirror having a circularly-symmetrical surface and two or more of the plurality of light emitters are arranged to direct the corresponding beams of light radially toward the circularly-symmetrical surface of the one mirror, the mirror operative to redirect the beams of light to travel in a direction parallel to a symmetry axis of the one mirror.   
     
     
         2 . A light source according to  claim 1  wherein the circularly-symmetrical surface of the one mirror is a conical surface. 
     
     
         3 . A light source according to  claim 1  wherein the circularly-symmetrical surface of the one mirror is a parabolic surface. 
     
     
         4 . A light source according to  claim 1  wherein the light sources are arranged in at least a first group and a second group with the light sources of the first group arranged at a first distance along the symmetry axis and the light sources of the second group are arranged at a second distance along the symmetry axis different from the first distance. 
     
     
         5 . A light source according to  claim 1  comprising demagnifying optics between the mirrors and the dynamically-addressable focusing element. 
     
     
         6 . A light source according to  claim 1  wherein the light emitters are operable to emit polarized light and the light emitters and mirrors are arranged such that polarization directions of the patches of light are substantially the same. 
     
     
         7 . A light source according to  claim 1  wherein path lengths along the light beams from each of the light emitters to the active area of the dynamically-adressable focusing element are substantially equal. 
     
     
         8 . A light source according to  claim 1  wherein the dynamically-adressable focusing element comprises a phase modulator or a deformable mirror or an array of micromechanical scanning mirrors. 
     
     
         9 . A light source according to  claim 1  comprising a control system connected to drive the dynamically-addressable focusing element to generate a desired light pattern at an image location. 
     
     
         10 . A light source according to  claim 9  wherein the control system is configured to drive an area corresponding to the patch of light for one of the light beams that is misaligned to compensate for the misalignment of the light beam. 
     
     
         11 . A light source according to  claim 9  wherein the control system is configured to drive parts of the active area corresponding to each of a plurality of the patches of light to emulate a lens wherein the lens has a focal length determined based on the desired light pattern. 
     
     
         12 . A light source according to  claim 9  wherein the control system is configured to drive parts of the active area corresponding to each of a plurality of the patches of light to emulate a prism wherein the prism has a slant and a slant direction determined based on the desired light pattern. 
     
     
         13 . A light source according to  claim 9  wherein the control system is configured to selectively drive parts of the active area corresponding to one or more of the patches of light to redirect the beams corresponding to the patches of light to a light dump. 
     
     
         14 . A light source according to  claim 9  wherein the control system is configured to control intensities of the light emitters. 
     
     
         15 . A light source according to  claim 1  wherein the light emitters comprise lasers. 
     
     
         16 . A light source according to  claim 15  wherein the lasers comprise laser diodes. 
     
     
         17 . A light source according to  claim 1  comprising a plurality of lenses, each associated with one of the individual light emitters and positioned to collimate light from the corresponding light emitter. 
     
     
         18 . A light source according to  claim 17 , wherein the lenses act only on one axis and the light beams are divergent on a second axis orthogonal to the one axis. 
     
     
         19 . A light source according to  claim 17 , wherein the light emitters have fast and slow axes on which the emitted light beams diverge differently and the lenses collimate the light beams on both the fast and slow axes. 
     
     
         20 . A light source according to  claim 1 , further comprising a spatial light modulator illuminated by light that has interacted with the phase modulating device. 
     
     
         21 . A light source according to  claim 1 , wherein the light emitters are configured to emit light of different wavelengths. 
     
     
         22 . A light source according to  claim 1 , wherein the light source includes lenses, optical elements and a dynamically addressable phase modulating device for use with lasers that emit one of red, green or blue laser light for color imaging. 
     
     
         23 . A light source of  claim 1 , wherein the dynamically addressable phase modulating device is configured to receive one of red, green or blue laser light in a time-multiplexed manner for color imaging.