Patent ID: 7627010

Claim:
A semiconductor laser comprising: a Fabry-Perot resonator; and a first coating on a rear facet of the Fabry-Perot resonator, wherein the first coating has a first reflectance, which is substantially constant in a first wavelength range, the first wavelength range extending to a first wavelength from wavelengths shorter than the first wavelength, has a second reflectance that decreases monotonically to a minimum, third reflectance in a second wavelength range, the second wavelength range extending from the first wavelength to a second wavelength that is longer than the first wavelength, and has a third reflectance that is substantially constant at the third reflectance in a third wavelength range, the third wavelength range extending continuously from the second wavelength to wavelengths longer than the second wavelength, wherein the first wavelength is shorter than a wavelength at which gain of the semiconductor laser is maximized when the semiconductor laser operates at a lowest operating temperature.