Abstract: A laser diode suitable for blue-green light emission utilizing type II heterojuctions of II-VI compound semiconductors. The laser diode comprises a layer 24 for confining electrons, a layer 26 for confining holes, and a quantum well layer which is formed bewteen the electron confinement layer 24 and the hole confinement layer 26 and allows the confined electrons and holes to recombine therein. The laser also comprises an electron barrier layer 23 and a hole barrier layer 27 for preventing diffusion of the electrons and holes beyond the barriers. The light emitted by the recombination is confined between the n-cladding layer 22 and a p-cladding layer 28.