Patent ID: 7061962

Claim:
A semiconductor laser diode comprising: a) a semiconductor substrate; and, b) a laser layer on said semiconductor substrate; and, c) an etched semiconductor surface on said laser layer, wherein said etched semiconductor surface includes a waveguide ridge and regions adjacent to said waveguide ridge; and, d) at least one gratingless section of said etched semiconductor surface; and, e) at least one grating section having gratings in or on said regions adjacent to said waveguide ridge including a strip shaped grating structure wherein said strip shaped grating structure includes strips of varying refractive index situated such that only small coupling is present between the light guided in said waveguide ridge and said strip shaped grating structure with coupling coefficient less than approximately 30 cm −1 ; and, f) at least one current drive electrode for independent pumping of sections of said laser diode; and g) wherein said semiconductor laser diode produces single longitudinal mode laser light.