Nanosecond, pulsed, frequency-modulated optical parametric oscillator

Summary form only given. For certain applications, a spectrum comprised of several longitudinal modes from an optical parametric oscillator (OPO) is desirable. For example, a broad spectrum can reduce speckle in remote sensing. This can be done by seeding the OPO on several longitudinal modes simultaneously so the spectrum is broad but does not fluctuate. This can be done by frequency modulating a cw seed laser so the sidebands and carrier all match longitudinal modes of the signal wave in the OPO. Such an FM OPO would also have applications in FM-modulation absorption measurements. We have demonstrated frequency modulation in a ring-cavity KTiOPO/sub 4/ OPO seeded by frequency-modulated light.