Hello everyone! and now about the holograms I shot after the exposure is complete, there are black spots, blur, low brightness problems, urgent solution. The light source I used was a 532 laser at 50MW. The subject is a nail, room temperature 23 degrees Celsius, humidity 46%. Then the photos taken are shown in the attached picture. Where is this trouble?
How can I improve this problem?https://drive.google.com/file/d/1UlixM6 ... drive_link
https://drive.google.com/file/d/1HwjiPa ... drive_link
https://drive.google.com/file/d/1Y_KMAC ... drive_link
https://drive.google.com/file/d/1k8E1RU ... drive_link
About uneven brightness, blur, black spots in photos taken
Re: About uneven brightness, blur, black spots in photos taken
It looks to me that the platform on which the nail is resting, and the nail, is moving. Whatever the nail is sitting on needs to be glued down or otherwise stabilised. The nail needs to be glued down onto the platform.
I think the nail may also be expanding. If the laser is powerful enough, or the exposure is long enough, the nail will heat slighty during exposure and will expand. Assuming the nail is made of iron, then the expansion is given by:
δL = ∝LδT
where δL is the change in length
∝ is the coefficant of expansion - 10^(-6) for iron
L is the original length - here assumed to be 76mm (3")
δT is the change in temperature.
If the change in length has to be below λ/2 (δL ~ λ/2) then
δT = (1/∝)(δL/L) ~ 0.3 deg C
That's not a lot, so the nail could be expanding.
By the way, I assume the laser is 50 milliwatts (mW), not 50 megaWatts (MW)
I think the nail may also be expanding. If the laser is powerful enough, or the exposure is long enough, the nail will heat slighty during exposure and will expand. Assuming the nail is made of iron, then the expansion is given by:
δL = ∝LδT
where δL is the change in length
∝ is the coefficant of expansion - 10^(-6) for iron
L is the original length - here assumed to be 76mm (3")
δT is the change in temperature.
If the change in length has to be below λ/2 (δL ~ λ/2) then
δT = (1/∝)(δL/L) ~ 0.3 deg C
That's not a lot, so the nail could be expanding.
By the way, I assume the laser is 50 milliwatts (mW), not 50 megaWatts (MW)