Semiconductor laser device having an active layer and a resonator having a single reflector or pair of reflectors

Abstract

There are provided a semiconductor laser device equipped with improved reflectors at the opposite ends of the resonator and capable of preventing any rise in the laser oscillation threshold current and reduction in the quantum efficiency due to temperature rise and a laser module comprising such a semiconductor laser device that operates effectively and efficiently at high temperature and can be downsized at reduced cost. The reflector 23 or 26 disposed at either end of the resonator 22 of a semiconductor laser device 21 according to the invention have a reflectivity that increases with the oscillation wavelength of the device within a range (.lambda..sub.1 to .lambda..sub.1) as a function of the operating temperature of the device. A laser module 31 according to the invention comprises such a semiconductor laser device 21 as a principal component. The semiconductor laser device 21 and therefore the laser module 31 comprising such a device have an improved temperature dependency because its reflector loss is reduced as the device temperature rises.

Dependencies are inferred from the claim text.