W. S. Cheung, Y. F. Cheung, H. T. Chen, R. S. Y. Hui, E. Waffenschmidt,
H. W. Choi,
By simply re-shaping the geometry of an LED chip to a stripe, its efficiencies
and functionalities can be enhanced. While a ~10% increase of optical
output makes it a more energy-saving emitter, the elongated geometry
stretches the light emission cone along the longitudinal axis, giving
an overall increase of emission area by fourfold. Light emission along
the LED stripe becomes much more uniform compared to the conventional
cubic chip, all achieved without the usage of external optics. The stripe
chips also sustain lower junction temperatures. LED chips adopting the
stripe geometry are demonstrated to be well-suited for lighting applications
due to their reduced luminous exitance compared to cubic chips.
Microphotographs of a (a) cubic (conventional) LED, (b) stripe LED and (c) stripe LED with inclined sidewalls, driven at 20 mA.
Letzte Änderung: E. Waffenschmidt, 12. Juli 2015