On Tue, 24 Jul 2001, Jim Choate wrote:
The optics used for focusing are NOT mirrors, they are (hopefully)
Okay, a have a chemical laser, something which burns tons of fuel (deuterium/fluorine) in a second in a resonant cavity. It is hence a not very small cavity. The wavelength is IR, several microns. This is high-power optics with a giant aperture (because, you don't want your optics to suffer the fate of your target, and because the resonant cavity itself is huge). Lenses don't like giant fluxes, either. Even a ruby laser pulse can break optics, or the rod, if it has a blemish. Lenses are *HEAVY*. Lenses are not flexible, so you can't use them for tracking. Lenses don't do very well when we're talking about few um IR. So what that leaves you with is an active mirror optics.
transparent at the frequency under use. A mirror on the other hand is required to be OPAQUE with respect to transmission, we want full, 100%, reflectivity. That means that every photon that hits that mirror interacts, loses some energy, and gets re-emitted.
Jim, I fear that bullet accident you had took a chunk out of one of your frontal lobes. Or at least lead to a hemorrhage to a lesion in that area. Have you ever had a MRI screen done? I'm serious.
I have a half dozen lasers, thank you very much.
-- Eugen* Leitl <a href="http://www.lrz.de/~ui22204/">leitl</a> ______________________________________________________________ ICBMTO : N48 10'07'' E011 33'53'' http://www.lrz.de/~ui22204 57F9CFD3: ED90 0433 EB74 E4A9 537F CFF5 86E7 629B 57F9 CFD3