An LED is provided comprising two or more light-emitting Type II interfaces wherein at least two of the Type II interfaces differ in transition energy by at least 5%, or more typically by at least 10%, and wherein at least one of the Type II interfaces is within a pn junction. Alternately, an LED is...http://www.google.se/patents/US8148742?utm_source=gb-gplus-sharePatent US8148742 - Type II broadband or polychromatic LEDs
