Optical apparatus and method for producing the same

A harmonic output stabilizing apparatus for a light source, wherein the light source is a short wavelength light source comprising:

• a semiconductor laser including an active region for providing gain and a distributed Bragg reflection (DBR) region for controlling an oscillation wavelength;
• and a wavelength converting device made of non-linear optical crystal,
• the apparatus comprising a control section for fixing the oscillation wavelength of the semiconductor laser at a phase-matching wavelength of the wavelength converting device by monotonously varying, in a first direction, a DBR current to be input to the DBR region while detecting a harmonic optical output of the short wavelength light source and detecting a DBR current value IO corresponding to a maximum value of the harmonic optical output, and then monotonously varying the DBR current in a second direction which is opposite the first direction beyond the detected value IO, then monotonously varying the DBR current again to set the DBR current at the detected value IO int he only first direction.

A harmonic output stabilizing apparatus for a light source, wherein the light source is a short wavelength light source comprising:

• a semiconductor laser including an active region for providing gain and a distributed Bragg reflection (DBR) region for controlling an oscillation wavelength;
• and a wavelength converting device made of non-linear optical crystal,
• the apparatus comprising a control section for fixing the oscillation wavelength of the semiconductor laser at a phase-matching wavelength of the wavelength converting device by monotonously varying, in a first direction, a DBR current to be input to the DBR region while detecting a harmonic optical output of the short wavelength light source and detecting and storing a DBR current value IO, corresponding to a maximum value of the harmonic optical output, and then independent of the harmonic optical output monotonously varying the DBR current in a second direction which is opposite the first direction beyond the stored value IO, and then monotonously varying the DBR current in the first direction again to set the DBR current to the stored value IO.