Simon's Holography Senior Project

nomiss · Post by **nomiss** » Tue Mar 06, 2012 3:41 pm

In this thread I will be keeping a detailed log of the progression of a three month long holography project that I am embarking on. I will be posting weekly updates on my project and on how it is progressing. I will also attach images of my setup and final product. Feel free to comment and add advice since I am new to holography. Throughout the project I will be using a Coherent Compass 315M-100 DPSS 532nm Laser. Output is tested at 101.2 mw. As for the holographic plates, I will be using Ultimate U08 plates ranging in size from 2.4"x2.4" up to 8"x10". Starting out I will be using a simple Denisyuk setup with some 2.4"x2.4" plates to experiment. Right now I have 40 2.4"x2.4" plates so I am thinking about experimenting with some chess and board pieces. As for front surface mirrors, I have a 5x7" 4x5" and four 1.5x1.5"s which I will be using later in some more advanced setups. Right now I am still gathering supplies for my main table which is going to consist of a granite countertop resting on some semi-inflated inner-tubes.

holomaker · Post by **holomaker** » Wed Mar 07, 2012 8:38 am

Ok Simon good luck and keep us posted !

holorefugee · Post by **holorefugee** » Fri Mar 16, 2012 9:40 pm

Please let us know the dimensions of your table. It will help my stiffness spreadsheet.

nomiss · Post by **nomiss** » Mon Mar 19, 2012 12:27 pm

Holorefugee, ill know the dimensions of my table by the end of today. I got these Barry Controls vibration mounts to use on each leg of my table. They are pretty small and are only about an inch and a half thick. Traditionally, they are mounted by screws, but that won't be an option since I don't feel like drilling through stone and risking cracking the table. http://i.ebayimg.com/t/Lot-4-Barry-Cont ... wMFgxNjAw/$(KGrHqIOKo0E6e52W4SUBPRBu18YUw~~60_57.JPG I was wondering if it would be best to just have them table resting on the vibration mounts or if they should be glued down.

holomaker · Post by **holomaker** » Mon Mar 19, 2012 1:09 pm

Hi Simon, the vibration isolators wou'nt need to be fastened but the legs should be glued/caulked together, if concrete blocks are used and if possible glued directlly to the floor as well, if thats not possible use 3/4' plywood pieces attached to leg bottom to act as foot.

nomiss · Post by **nomiss** » Tue Mar 20, 2012 9:58 am

The dimensions for the granite slab are, 4x8ft and 1 1/4 inch thick. When I was testing out the concave mirror last night i noticed splotches on the dissipated light. I think it is due to dust on the concave mirror. How should I fix this?

Kiffdino · Post by **Kiffdino** » Tue Mar 20, 2012 2:02 pm

build a cage around your entire table with curtains. keeps the dust out and the optics clean + no heat fluctuations, im building one myself at the moment.

Johnfp · Post by **Johnfp** » Wed Mar 21, 2012 9:20 am

Blow the surface of the mirror off with canned air. If you need further cleaning then try to rinse rinse with warm soapy water then warm water with a little photo flow. Try not to rub the surface unless you really have to but do it gently. Then blow the water off with air. Try to clean your front surface mirrors as little as possible as over the years, that extra wear and tear really starts to compound.

You may not even need to clean it. Make a hologram and see if you notice the blotchs.

nomiss · Post by **nomiss** » Wed Mar 21, 2012 7:14 pm

Today I built my table. It consists of a granite slab which has the dimensions of 64(need to double check, might be more)x43.5x1.25 in. or 1.62x1.1x.031m. Granite weighs 2691 kilograms per cubic meter so the slab weighs 327 lbs (1.62x1.1x.031=.0552 Cubic Meters- .0552x2691=148.54kg or 327lbs.) As of now, the barry controls vibration mounts that I'm using are past capacity and are basically useless. In order to fix this I bought five(only need four) Barry Stable-Level SLM-6A mounts.

Their individual weight range is min. 150lbs and a max. of 600lbs. Im concerned the table won't be heavy enough for the mounts to work properly. Your opinion? For the base of each legs I used a 24x24in piece of plywood, which I'm going to shim once I have the new mounts for increased stability. I am also going to place four more cinder blocks on each piece of plywood to increase stability. Everything was glued together with PL 375, which then I allowed to dry for 15 minutes. After that, I placed the slab on top to add pressure to the drying process. The table wasn't completely level so I had to use washers in-between the mounts and table to level it out. Here's some pictures of everything.

nomiss · Post by **nomiss** » Wed Mar 21, 2012 7:22 pm

I just want to say that this site has ridiculous picture constraints. Pictures can't be over 800x600 pixels or over 1mb. Also no more than five pictures are allowed per post. Because of this, I had to resize all of my pictures which I took with my iPhone (took me 15 minutes). To whoever runs this site I would like to say please make it easier to upload pictures. But anyways, here are the rest.

I also have a 4x10ft slab, which weighs >600lbs (required minimum weight for vibration mounts) but then again its over 600lbs and 10ft long and will be almost impossible to get into the room that I am using. In one of the pictures you can see two parallel support beams which are running along the ceiling. I will be attaching some optics, with a vice, to one of them for a Denisyuk setup.