Getting two flats aligned well enough to produce that first fringe is not trivial.
It takes fine adjustment controlling elements. HeNe lasers go along way to aid this effort. Reflections and all. I have a Davidson D304, 5.5" aperture unit here in the home lab. Not useful for any machine tool application, but good for qualifying the flats one might use. Cheers Cal ----- Original Message ----- From: "Jon Elson" <[email protected]> To: "Enhanced Machine Controller (EMC)" <[email protected]> Sent: Thursday, September 09, 2010 12:36 Subject: Re: [Emc-users] [OT] Interferometry > Kirk Wallace wrote: >> >> A very accurate sphere (amateur made, using Foucault tester) is used as >> a standard to compare against the mirror being tested. I am wondering if >> a version of this could be used for testing machine axis accuracy using >> two accurate flats, one on the axis table, one stationary with the test >> rig? Flats can be difficult to make, but it is possible. >> > To see the fringes (Newton's rings) the flats have to be very close > together, or very > highly coherent light needs to be used. Even air currents in the room > will blur the > fringes if separated by more than a few inches. I can see checking > parallelism > and straightness of motion with a fixed flat and one riding on the > slide. I'm not > sure what else you could do with a pair of flats. > > It is probably a lot easier to measure flatness of parts with spotting > dye and a > granite surface plate, and then assume that when you put it together it > will move > in a straight line. > > Jon > > ------------------------------------------------------------------------------ > This SF.net Dev2Dev email is sponsored by: > > Show off your parallel programming skills. > Enter the Intel(R) Threading Challenge 2010. > http://p.sf.net/sfu/intel-thread-sfd > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ This SF.net Dev2Dev email is sponsored by: Show off your parallel programming skills. Enter the Intel(R) Threading Challenge 2010. http://p.sf.net/sfu/intel-thread-sfd _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
