Monolithic edge-emitting semiconductor diode arrays

A light emitting module comprising a monolithic edge-emitting semiconductor diode array chip and a driver unit comprising a plurality of driver circuits, wherein the monolithic edge-emitting semiconductor diode array chip comprises

• a conductive substrate;
• a plurality of semiconductor layers arranged on the conductive substrate, the semiconductor layers including
• one or more active region layers sandwiched between upper and lower cladding layers;
• and
• one or more separation layers arranged between the conductive substrate and the lower cladding layer,
• front and back chip facets;
• a plurality of ridges, each extending between the front and back chip facets and each having respective pairs of sides that define a waveguide in the active region layers, wherein the front chip facet defines an output coupling termination for the waveguides;
• a trench extending between each pair of adjacent ridges, each trench having a base lying at a depth that is within or below the one or more separation layers;
• and
• a one-dimensional array of diodes, which are laser diodes, superluminescent diodes or semiconductor optical amplifiers, each diode having a gain region defined by one of the waveguides in combination with the active region layers and each being configured to emit an output beam from the front chip facet when driven under forward bias,
• wherein each diode of the one-dimensional array has its own upper and lower contacts that are arranged to contact the semiconductor layers above and below the active region layers so that each diode is independently drivable, wherein the upper and lower contacts form anode and cathode diode contacts to respective ones of the diodes or vice versa, and wherein the driver circuits are connected across the anode and cathode contacts of respective diodes of the monolithic edge-emitting semiconductor diode array chip.

A display projector module comprising:

• a light emitting module comprising a monolithic edge-emitting semiconductor diode array chip and a driver unit comprising a plurality of driver circuits, wherein the monolithic edge-emitting semiconductor diode array chip comprises:
• a conductive substrate;
• a plurality of semiconductor layers arranged on the conductive substrate, the semiconductor layers including
• one or more active region layers sandwiched between upper and lower cladding layers;
• and
• one or more separation layers arranged between the conductive substrate and the lower cladding layer,
• front and back chip facets;
• a plurality of ridges, each extending between the front and back chip facets and each having respective pairs of sides that define a waveguide in the active region layers, wherein the front chip facet defines an output coupling termination for the waveguides;
• a trench extending between each pair of adjacent ridges, each trench having a base lying at a depth that is within or below the one or more separation layers;
• and
• a one-dimensional array of diodes, which are laser diodes, superluminescent diodes or semiconductor optical amplifiers, each diode having a gain region defined by one of the waveguides in combination with the active region layers and each being configured to emit an output beam from the front chip facet when driven under forward bias,
• wherein each diode of the one-dimensional array has its own upper and lower contacts that are arranged to contact the semiconductor layers above and below the active region layers so that each diode is independently drivable, wherein the upper and lower contacts form anode and cathode diode contacts to respective ones of the diodes or vice versa, and wherein the driver circuits are connected across the anode and cathode contacts of respective diodes of the monolithic edge-emitting semiconductor diode array chip, and
• the display projector module further comprises:
• collimating optics configured to transform the output beams output from the chip into a plurality of collimated output beams;
• and
• a beam scanner for raster scanning the output beams to form an image.

A vision system configured to be placed on a human head incorporating a display projector module into a head-mountable unit, the display projector module comprising:

• a light emitting module comprising a monolithic edge-emitting semiconductor diode array chip and a driver unit comprising a plurality of driver circuits, wherein the monolithic edge-emitting semiconductor diode array chip comprises:
• a conductive substrate;
• a plurality of semiconductor layers arranged on the conductive substrate, the semiconductor layers including
• one or more active region layers sandwiched between upper and lower cladding layers;
• and
• one or more separation layers arranged between the conductive substrate and the lower cladding layer,
• front and back chip facets;
• a plurality of ridges, each extending between the front and back chip facets and each having respective pairs of sides that define a waveguide in the active region layers, wherein the front chip facet defines an output coupling termination for the waveguides;
• a trench extending between each pair of adjacent ridges, each trench having a base lying at a depth that is within or below the one or more separation layers;
• and
• a one-dimensional array of diodes, which are laser diodes, superluminescent diodes or semiconductor optical amplifiers, each diode having a gain region defined by one of the waveguides in combination with the active region layers and each being configured to emit an output beam from the front chip facet when driven under forward bias,
• wherein each diode of the one-dimensional array has its own upper and lower contacts that are arranged to contact the semiconductor layers above and below the active region layers so that each diode is independently drivable, wherein the upper and lower contacts form anode and cathode diode contacts to respective ones of the diodes or vice versa, and wherein the driver circuits are connected across the anode and cathode contacts of respective diodes of the monolithic edge-emitting semiconductor diode array chip, and
• the display projector module further comprises:
• collimating optics configured to transform the output beams output from the chip into a plurality of collimated output beams;
• and
• a beam scanner for raster scanning the output beams to form an image.