University College Cork

Oculus, Vr, LLC

Pleun Maaskant

Brian Corbett

Paul Martin Lambkin

Bill Henry

Brendan John Roycroft

Edmund Anthony O'Carroll

The invention relates to a SLED device emitting light from a substrate side, configured to suppress lasing, and comprising a reflective element () on a front surface of a substrate () configured to redirect an optical beam (light) onto a back surface of the substrate (). In one embodiment the device can be used for making a compact RGB (red-green-blue) projector.

Superluminescent light emitting diode (SLED) device

An integrated LED device is provided. The LED device includes a substrate. The LED device includes a semiconductor material including a light generating layer and positioned on the substrate. The semiconductor material and/or the substrate are configured to control light internally to output quasi-collimated light from a light emitting surface of the LED device. The LED device includes an optical component positioned at the light emitting surface and configured to receive quasi-collimated light exiting the light emitting surface and to alter one or more optical properties of at least some beams of the quasi-collimated light.

Micro-LED array with filters

An array of highly efficient micro-LEDs where each micro-LED is an integrated diode structure in a mesa, in which the mesa shape and the light-emitting region are chosen for optimum efficiency. A single one of the micro-LEDs includes, on a substrate and a semiconductor layer, a mesa, a light emitting layer, and an electrical contact. The micro-LEDs in this device have a very high EE because of their shape. Light is generated within the mesa, which is shaped to enhance the escape probability of the light. Very high EEs are achieved, particularly with a near parabolic mesa that has a high aspect ratio. The top of the mesa is truncated above the light-emitted layer (LEL), providing a flat surface for the electronic contact on the top of the semiconductor mesa. It has been found that the efficiency is high, provided the top contact has a good reflectivity value. Also, it has been found that efficiency is particularly high if the contact occupies an area of less than 16% of the truncated top mesa surface area. This feature also helps to achieve a more directional beam in the case of the device being an LED.

Light emitting mesa structures with high aspect ratio and near-parabolic sidewalls

An initial epitaxial layer of GaN is grown on a sapphire substrate. The epitaxial layer is then etched in a reactive ion etch (RIE) chamber. This etching acts preferentially at defects, causing them to become enlarged cavities. The cavities are too large in proportion to the crystal lattice to act as defects in the usual sense, and so a further GaN epitaxial layer fills into the cavities. Thus, propagation of defects is avoided.

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Cork, Ireland

Pleun Maaskant