Abstract: An emergency light for providing illumination during emergency conditions with a housing, a light source, and a drive arrangement for driving the light source between retracted and extended positions. Flanges, which can be removable, can project from the housing. Fastening arrangements each comprising a mounting bolt in combination with a locking clip can retain the emergency light in relation to a support surface. A motor in combination with a drive screw threadedly engaged with the light source can form the drive arrangement to produce an axial movement of the light source. A limit switch can sense a position of the light source, and a reflector can guide light from the light source. An emergency condition sensor can trigger an extension and illumination of the light source. A battery can power the light during a power failure. Plural lights and a central control unit can form an emergency lighting arrangement.

Abstract: An array of highly efficient micro-LEDs (100) and a manufacturing process are described. Each micro-LED (100) is an integrated diode structure in a mesa (105), in which the mesa shape and the light-emitting region (104) are chosen for optimum efficiency. A single one of the micro-LEDs (100) comprises, on a substrate (101) and a semiconductor layer (102), a mesa (103), a light emitting layer (104), and an electrical contact (106). 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 nearparabolic mesa that has a high aspect ratio. The top of the mesa is truncated above the light-emitting layer (LEL), providing a flat surface for the electrical contact (106) 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.