Yes, I have an Agilent 5517D which is a frequency stabilized two frequency laser that I got on Ebay.
How fast can the counters on the 5I20 count? I would need a pair of perhaps 32 bit counters that can count at more than 4 MHz and can be read out "simultaneously". (Actually, copied into another set of registers at the same time and then transferred to the host before the next copy time). Ken Anders Wallin wrote: >> A laser interferometer is on my todo list. I've acquired all of the >> optics on ebay for a total of a few hundred dollars. I've built a power >> supply. The major part I'm missing is the counting and interpolating >> electronics with a computer interface. >> > > Hi Ken, > > the heterodyne interferometers I have found described mostly use a > two-frequency laser which emits two orthogonal polarizations with > slightly (500kHz? or in your case 4 MHz) different frequency. Did you > find a Zeeman-stabilized two-frequency laser on ebay? Or are you > planning to DIY and put magnets around a normal HeNe tube? Sams Laser > FAQ has a description: > http://www.repairfaq.org/sam/laserchn.htm#chndzees > > The other method is to use an acousto-optic modulator to shift the > frequency of the light. But the papers I've found use two modulators, > and I only have one to spare right now... > > If I can either find a two-frequency HeNe or DIY with magnets then I'd > be interested in testing this, possibly with the m5i20 (already has > fpga code for fast encoder counters) for data acquisition. > > Anders > > ------------------------------------------------------------------------------ > This SF.Net email is sponsored by the Verizon Developer Community > Take advantage of Verizon's best-in-class app development support > A streamlined, 14 day to market process makes app distribution fast and easy > Join now and get one step closer to millions of Verizon customers > http://p.sf.net/sfu/verizon-dev2dev > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ This SF.Net email is sponsored by the Verizon Developer Community Take advantage of Verizon's best-in-class app development support A streamlined, 14 day to market process makes app distribution fast and easy Join now and get one step closer to millions of Verizon customers http://p.sf.net/sfu/verizon-dev2dev _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
