F110 short report English

Dear aneves,              

many, many thanks for your posting!

With the Bath interferometer you can test optics till f/4 correctly, but a f/3 spherical mirror
you probably can get problems in the matter you describe them. With a f/4 mirror there
are no problems.

This interferometer works with two beams and not exactly on optical axis. These two
beams distance should be 4-5 mm, no more, best 4 mm and parallel till 3-4 meters. After
fixing the laser diode I fix the cube alignable, the two beams distance about 4 mm, parallel
and at last the bikonvex lense with 7-10 mm fokus in the first beam

bath-im.jpg

Important is, that the second beam is concentrated in the first light conus after passing the
bikonvex lense, it sould be 5 mm in diameter and about 2 mm thick. The cube is 15x15x15 mm till 20 mm.

bath-em.jpg

This is the way, how the Bath interferometer works. You can test optics with straight
fringes and circles for rotation symetry.

How big is your hole? The reference beam #2 should be near your hole. If you send me
one of your fringes pattern, I can put it on my server for you. You just write in your posting

@.jpg

Can you let us see, how your Bath interferometer
looks like? The upper picture is the one I use. Feel free to ask us more questions for
that.