Interferometer First light - WooHoo!

I've been having fun over the past few stormy nights building a new Interferometer for testing (non-flat) mirrors and optics. I already built a common path interferometer for testing flat mirrors, but this one is for testing conic sections (and lenses when used with a collimating flat!)

This interferometer splits a collimated laser beam into a test wave front and a reference wave front. By recombining the two wavefronts a pattern of interference fringes are generated which can be projected onto a screen or photographed.

The image below is the first successful test of the rig following several nights of intensive fiddling, alteration and hi-tech cludgery! And way-hay - it works!!! The mirror under test is an 8" f/6 mirror. I haven't analysed the fringe pattern yet (lots more fiddling to improve the image clarity and contrast first!) but just had to share this little triumph!

This interferometer is well capable of measuring surface deformation as small as 1/20th of a wave, and with a bit more fiddling should be capable of even finer resolution.

Phil.
(Rediculously happy!!! )

WOW, that is some achievement Phil. I'd love to see that sometime.

Oh all right then... I'll bring it along to Galway with me!

Phil.
(Still with a painfully smug grin on his face! )

Brilliant Phil! Getting a pattern at all is an achievement.

Oh all right then... I'll bring it along to Galway with me!

Woohoo, you're comin' to Galway!! Thats great news. When you going down?

Thats the best news I've had all day!

Crack of dawn on Saturday morning... please have the coffee brewing when I arrive! Probably leave Bray around 6am and get down to Galway by 9ish. Can't remember how long it took last year - any ideas?

Phil.