Patent attributes
A laser device with frequency conversion, the device comprising a complex optical cavity comprising two cavity parts with two different levels of circulating intracavity power wherein there is placed at least one non-linear crystal (30) is placed within the cavity part of higher circulating power and an active medium (21) in the cavity part of lower circulating power, the power enhancement achieved in two steps and the total enhancement being the product of the enhancement factors in each step, providing additional freedom in design allowing both the condition for high enhancement of the interacting laser power inside the intracavity non-linear crystal and the condition for maximum power output from the laser to be satisfied simultaneously and wherein said complex optical cavity the first cavity part provides the initial step of power enhancement and comprises at least a laser cavity back mirror (20), highly reflective about a laser radiation fundamental frequency ω, and an active (gain) medium.