OPTICAL SEMICONDUCTOR ELEMENT AND OPTICAL COHERENCE TOMOGRAPHY DEVICE EQUIPPED WITH OPTICAL SEMICONDUCTOR ELEMENT AS LIGHT SOURCE

摘要

PROBLEM TO BE SOLVED: To provide an optical semiconductor element which can suppress a luminescence intensity in a short wavelength region even when a carrier injection concentration is set high for achieving a high output and a wide spectrum half band width.SOLUTION: An optical semiconductor element comprises a first clad layer, a second clad layer and an active layer including a luminescent layer and a barrier layer which are arranged between the first clad layer and the second clad layer, in which a spectrum of light emitted from the luminescent layer has a central wavelengthλc and a spectrum half band widthΔλ. At least one of the first clad layer and the second clad layer has a light absorption part for absorbing light of a wavelength ofλs represented as the following formula (1):λs<(λc-(Δλ/2)) Formula (1)