"Pulled Parabola"

Can anyone tell me what a "pulled parabola" mirror is and how it compares to the regular parabolic mirror? Does it give better images and how is it done? Thanks for any info you can give me.

Bob

There is an article in the last S&T about this. Basically you buy a cheaper spherical mirror, then using mechanical means, you flex or pull the mirror into a parabola.

I dont think it will give "better" images than a true parabola, but its easier to make a spherical figure than a true parabola. (from what I've read) Which is why some have done this.

I think this is what you mean, if not then sorry.

Donnie

I agree with Donnie that the quality is probably not better but in theory if done correctly you are supposed to be able to achieve well beyond diffraction limited. The other possible advantage is that the procedure is suppose to work best with a thin mirror about a 10 to 1 ratio.

Dave

As I recall, this technique becomes sort of impractical if the mirror is sufficiently large...