ks_physicist
Newly Enlightened
I have been thinking of the problem of using higher power lasers while minimizing the risk of eye damage, and I have begun to wonder about alternate pumping methods for the YAG or Vanadate laser stage.
What I'm thinking of is constructing a laser that is normally driven by a lower power IR diode, creating a typical <5mw green beam that would present a low eye hazard. This would permit aiming. Then, one could fire a high power pulse with a trigger.
Two methods come to mind immediately. First, perhaps a suitable IR diode could be chosen which has a lasing threshhold low enough to pump the <5mw aiming beam, but which can be briefly driven to much higher output. I have read of solid state laser diodes being driven to high instantaneous power output levels using a current pulse, giving them a brief output power that would, if it were CW, would destroy the diode.
I have not experimented with pulse pumping of laser diodes, so I do not know how feasable this would be.
The second idea is to mount the YAG/Vanadate rod in an elliptical polished optical cavity for flash pumping. The optics would be arranged so that under normal circumstances, the IR laser diode is pumping the laser rod. An independent circuit could then fire the flash tube, initiating a high power pulse. I'm wondering if the waste beam from the back of the crystal, which would fire into the pump LD, would damage the LD.
Thoughts?
What I'm thinking of is constructing a laser that is normally driven by a lower power IR diode, creating a typical <5mw green beam that would present a low eye hazard. This would permit aiming. Then, one could fire a high power pulse with a trigger.
Two methods come to mind immediately. First, perhaps a suitable IR diode could be chosen which has a lasing threshhold low enough to pump the <5mw aiming beam, but which can be briefly driven to much higher output. I have read of solid state laser diodes being driven to high instantaneous power output levels using a current pulse, giving them a brief output power that would, if it were CW, would destroy the diode.
I have not experimented with pulse pumping of laser diodes, so I do not know how feasable this would be.
The second idea is to mount the YAG/Vanadate rod in an elliptical polished optical cavity for flash pumping. The optics would be arranged so that under normal circumstances, the IR laser diode is pumping the laser rod. An independent circuit could then fire the flash tube, initiating a high power pulse. I'm wondering if the waste beam from the back of the crystal, which would fire into the pump LD, would damage the LD.
Thoughts?
