LIGHT-EMITTING DIODES

Sapphire produces LEDs, including arrays up to 100 mm x 100 mm. A typical unit measures 20 mm x 20 mm and consists of 32 x 32 elements. Of particular interest is Sapphire's idea of building a UV-emitting LED that could excite red, green, and blue phosphors deposited directly on the LED substrate. This device would allow the fabrication of a color display using very efficient photoluminescent phosphors that would be applied to the finished LED. The feasibility of this idea was demonstrated last year, although the brightness was very low due to the low output (low efficiency) of the LED.


Published: December 1994; WTEC Hyper-Librarian