Free space multiple laser diode modules
Systems, devices, and methods for optical engines and laser projectors that are well-suited for use in wearable heads-up displays (WHUDs) are described. Generally, the optical engines of the present disclosure integrate a plurality of laser diodes (e.g., 3 laser diodes, 4 laser diodes) within a single, hermetically sealed, encapsulated package. Such optical engines may have various advantages over existing designs including, for example, smaller volumes, better manufacturability, faster modulation speed, etc. WHUDs that employ such optical engines and laser projectors are also described.
1. A method of operating an optical engine, the optical engine comprising a plurality of laser diodes hermetically sealed in an encapsulated package, the method comprising:
causing the plurality of laser diodes to generate laser light, comprising:
causing a first laser diode of the plurality of laser diodes to generate first laser light;
causing a second laser diode of the plurality of laser diodes to generate second laser light; and
causing a third laser diode of the plurality of laser diodes to generate third laser light;
receiving the laser light from each of the laser diodes by a single face of an director element;
redirecting, by the single face of the optical director element, the received laser light toward an optical window of the encapsulated package;
collimating, by a plurality of collimation lenses, the laser light from the laser diodes that exits the encapsulated package via the optical window to generate a plurality of laser light beams; and
combining, via a beam combiner, the plurality of laser light beams received from each of the collimation lenses into a single aggregate beam, comprising:
receiving, by a first optical element of the beam combiner, the first laser light generated by the first laser diode;
redirecting, by the first optical element, the first laser light to travel in a first direction;
receiving, by a second optical element of the beam combiner, the first laser light travelling in the first direction and the second laser light generated by the second laser diode;
transmitting, by the second optical element, the first laser light travelling in the first direction;
redirecting, by the second optical element, the second laser light to travel in the first direction;
receiving, by a third optical element of the beam combiner, the first laser light traveling in the first direction, the second laser light traveling in the first direction, and the third laser light generated by the third laser diode;
transmitting, by the third optical element, the first laser light traveling in the first direction and the second laser light traveling in the first direction; and
redirecting, by the third optical element, the third laser light to travel in the first direction.
2. The method of claim 1 wherein:
causing a first laser diode of the plurality of laser diodes to generate first laser light comprises causing the first laser diode to generate the first laser light as red laser light;
causing a second laser diode of the plurality of laser diodes to generate second laser light comprises causing the second laser diode to generate the second laser light as green laser light; and
causing a third laser diode of the plurality of laser diodes to generate third laser light comprises causing the third laser diode to generate the third laser light as blue laser light.
3. The method of claim 2 wherein causing the plurality of laser diodes to generate laser light further comprises causing an infrared laser diode to generate infrared laser light.