Laser generating apparatus

DETAILED DESCRIPTION It is therefore an object of the present invention to provide a laser generating apparatus in which generation of the reverse traveling wave, which returns light to the laser light source, is suppressed for eliminating the necessity of providing the optical isolator.
The present invention provides a laser light generating apparatus including a laser light source for radiating the laser light, an optical resonator for resonating the laser light radiated from the laser light source, a non-linear optical crystal element having an anti-reflection film formed on a laser light incident surface thereof, and an aperture for interrupting the light reflected by the non-linear optical crystal element within the optical resonator.
The non-linear optical crystal element is arranged in the light resonator so that a line drawn normal to the laser light incident surface will be obliquely inclined relative to the optical axis of the laser light resonated within the optical resonator.
Preferably, the non-linear optical crystal element is tilted in a direction which minimizes the effect on the phase matching condition of the laser optical resonated within the light resonator so that the line drawn normal to the laser light incident surface is obliquely inclined with respect to the optical axis of the laser light resonated in the light resonator.
With an angle .
alpha.
between a line drawn normal to the laser incident surface of the non-linear optical crystal element and the optical axis of the laser optical resonated in the light resonator, an angle .
beta.
the effective diameter of the aperture subtends with respect to the non-linear optical crystal element and with a spreading angle .
delta.
of the light reflected by the laser incident surface, the equation the relation of 2.
alpha.
.
gtoreq.
(.
beta.
+.
delta.
) preferably holds.