External resonator-equipped semiconductor laser element

Abstract

Abstract PURPOSE:To prevent fluctuation of oscilation wavelength due to variation of temperature, by forming a reflection preventing film on one side of output face of a laser element, and by causing light put out from said face to reflect and return through etalon at least once. CONSTITUTION:By providing a semiconductor laser element 3 with two parallel output faces 4 and 5, a resonator is provided and, at the same time, the element 3 is prevented from resonance. In this mechanism, one output face 5 is provided with a reflection-preventing film, such as SiO2 film etc., to eliminate reflection, and all the lights 7 put out therefrom are converted into parallel rays using a lens 8. And then, these lights are vertically radiated into two etalons 1 and 2 having different lengths, and the lights are caused to reflect and return from the reflecting faces 9 of the etalon 2 which are set to 100% reflecting positions. While resonance wavelength existing in gain distribution of the element 3 is thus oscillated in the etalons 1 and 2, as it is possible to provide the etalons 1 and 2 by keeping away from the element 3, the etalons 1 and 2 can be prevented from being influenced by the heat generating in the element 3.

Inventors

• 👤 Ritsuo Hasumi

Bibliographic Details