High Energy Lasers: Questions & Answers

[0xDEADBEEF]

Does someone here know about high energy lasers?

As I understand it, at a certain field strength you damage your optical media, but I know high power cw lasers do exist, so I wonder:

1) How do you shutter a high power laser?
2) Is it possible to join two laser beams. The only way I see would be with a polarizing beam splitter in reverse, but you can only do that once and the medium hast to survive.
3) Is the key to success to tune all your mirrors exactly to the laser frequency?

 

[Redbelly98]

Usually, it's the optical surface coatings that damage before the actual optical material.

Higher power lasers typically use a larger area beam, so that the intensity (power/area) is kept below the damage threshold.

1) lasers can be shuttered with a black anodized aluminum stop, with a heatsink if necessary. The thermal conductivity of aluminum and heatsink would dissapate the heat.

2) Yes, a polarizing beam splitter can combine two beams that are each linearly polarized. The resulting beam will be unpolarized.

3) Mirrors that are highly reflective at the laser frequency are used so that losses are minimal. Mirrors often work over a broad range of wavelengths, eg. "visible", "near ir", etc.