Holographyforum.org / holowiki.org

Okay, making a Denisyuk hologram with ref beam coming at low angle straight at, and through, the plate. But in a new arrangement, I get a strange result... the image (if you can call it that) only appears if the recon light illuminates the plate from the side. A little detective work... following th...

If you illuminate the object through the lens - that is, you light the object with light that's passed through the lens - then... In the words of Tom Lehrer, "These are all the effects that I have now disc-a-a-a-vered, there may be many others, but they haven't reached H-a-a-rvard" Okay, ...

Yes, late 80s, early 90s is the time period I saw telephone with magnifier. Nice to know who made it!

All good information, thank you. I will play, I promise.

I think the only two holograms I ever saw before recently was a couple of transmission holograms illuminated with HeNe laser light. One showed a toy car and the other had a magnifying glass in front of a phone dial... I can't remember if the numbers it was magnifying were on a rotary dial or touch t...

Tested a new laser making a couple Denisyuk holograms. The plates were tilted vertical, so used half wave plate to rotate the beam polarizations vertical. No woodgraining, yay. Blackened the plate edges with a marker. None of that wavy intensity change across the picture, yay. If only I had not slip...

BobH, i can certainly imagine these alignment issues. I'm happy to follow the expert consensus, and I will order 10 micron and 25 micron pinholes this week. Ed, Dinesh, it is end of semester and I've got to get some work done! Already I spend too much time mulling over the good ideas y'all have prov...

I am familiar with using objectives to focus laser beams (in order to create optical traps. So I know about Airy disks, Rayleigh criterion, and so on. When I do those calculations, a 16x objective focuses a typical 2 mm diameter beam to an Airy disk smaller than 8 microns, and a 40x can squeeze it t...

Okay in my other thread, I promised to ask only one question per week. I asked a question last Sunday and its only Friday. But its Friday after 5 pm, so I'm declaring it another week. I am planning to purchase pinholes next week. I have a couple 40x objectives and a couple 16x objectives. What pinho...

Yes I'm hoping others will add. I've tried to photo in complete surrounding dark. I don't think that the hologram is particularly noisy or weak. I used pretty much the same angle of ref,recon beam for all my tests, so that is something to vary. Top surface is clean, good specular reflector (I've see...

To avoid cross talk, the refs must be fairly well angularly separated, which will not get the smooth effect you're looking for. Yes, this is what I was afraid of. Either all the shadows blur together from too many reference beams or you'll have the shadow jump in a few discrete steps from too few r...