Unwanted fringes
Re: Unwanted fringes
Petr, you got your comment in just at the same time as I did! I think we both agree it's object motion
Re: Unwanted fringes
Here are more images of the resonances of guitars and other stringed instruments visualized by holographic interferometry, from the Rossing book (ISBN 0-201-15727-6)
Hope to see some good results!
As you can see there have been many successful guitar interferometry holograms made. The problem here is not just the guitar moving, but the reference surface, plus a white card in a lens mount along with the speaker have the fringes. Either the reference mirror or object illumination is moving, or more than likely it is a multimode laser. Only a new laser will tell. Hope to see some good results!
"We're the flowers in the dustbin" Sex Pistols
Re: Unwanted fringes
Just checking to see if any progress has been made on this project. Looks like fun once you get over the laser!
"We're the flowers in the dustbin" Sex Pistols
Re: Unwanted fringes
We are in touch with Peter and are planning my visit in their lab. Sure we will post the result.Just checking to see if any progress has been made on this project. Looks like fun once you get over the laser!
Re: Unwanted fringes
Confirmed. The laser was mode hopping. There were some minor problems in the setup as well (too much components, too long exposure time etc.), but the laser was the major one. With my Lasnova 50 mW (thanks, Phil!), everything worked fine.