Abstract Passive pulse transmission mode (PTM) operation is established in a Q-switched laser by means of a parametric oscillator located within the resonator of the laser which functions as a pump for the oscillator. The oscillator is adapted to deplete the pump at the moment the incavity pump power reaches a maximum, resulting in highly efficient conversion of pump power to signal and idler power. In one embodiment, one of the laser reflectors is made highly transmissive to the nonresonant signal radiation, and the oscillator is made singly resonant (SRO) at the idler frequency, resulting in a substantial fraction (ideally at least one-half) of the laser power being coupled out of the cavity in twice the round trip time of the laser resonator, but at the signal wavelength. Since the SRO is tunable, the short, high power output pulse is also tunable from the pump wavelength to longer wavelengths. Other embodiments utilizing doubly resonant oscillators and ring-type configurations are also disclosed.
Optical pulse transmission mode apparatus comprising a Q-switched laser having a primary resonator for sustaining the build up of a Q-switched pump pulse of radiation, and a parametric oscillator having a secondary resonator disposed within said primary resonator, said oscillator being adapted to be pumped by said laser and to deplete said pump pulse power at a point in time when the power of said pulse in said primary resonator reaches its maximum.
Claim 2
Dependent Claim
73 words
Optical pulse transmission mode apparatus comprising a Q-switched laser having a primary resonator for sustaining the build up of a Q-switched pump pulse of radiation, and a parametric oscillator having a secondary resonator disposed within said primary resonator, said oscillator being adapted to be pumped by said laser and to deplete said pump pulse power at a point in time when the power of said pulse in said primary resonator reaches its maximum.
Claim 3
Dependent Claim
58 words
The apparatus of claim 1 wherein said parametric oscillator is adapted to be singly resonant at only one of its idler or signal frequencies and nonresonant at the other of said frequencies, and said primary resonator is adapted to be in a high Q-condition for pump pulse radiation and a low Q-condition for radiation at said nonresonant frequency.
Claim 4
Dependent Claim
16 words
The apparatus of claim 2 in combination with means for frequency tuning said singly resonant oscillator.
Claim 5
Dependent Claim
31 words
The apparatus of claim 1 wherein said parametric oscillator is doubly resonant at its idler and signal frequencies and said primary resonator is in a high Q-condition for pump pulse radiation.
Claim 6
Dependent Claim
27 words
The apparatus of claim 4 wherein said primary resonator is a ring-type resonAtor having a plurality of legs, said oscillator being disposed in one of said legs.
Claim 7
Dependent Claim
13 words
The apparatus of claim 1 wherein said laser comprises a passively Q-switched laser.