Optical Bench

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Stability is very important to holography. In order to hold the relative alignments of the optics the table must be stiff. It also must be isolated from vibrations coming from the ground and air. To learn about table design see Table Design Theory . To see pictures of lab's set up for making holograms see a Tour of Holography Labs.


Pavers make a great table if you only need to have a 1' x 1' table. There many setups that can be made on a small table. See Laser Pointer Holography for examples.

Concrete Tables

Concrete tables are inexpensive easy to fabricate and very stiff. This comes at the price of weight. The weight helps to isolate the table from vibrations coming from the ground. Many sucessful tables have been made 4'x8'x3.5" thick.

Sand Tables

Sand tables are the easiest to use, cheapest to make and most versatile tables available. They have made more holograms than any other home built table.

When building a sand table it is important to use dust free sand. The kind sold for ash trays works well.

Lon Moore's last table was 4x8' of 3.5" thick concrete with brick and mortor side walls enclosing sand 2' deep. It was extremely versatile and stable.

Making optic mounts for a sand table is extremely quick and easy. Most people use PVC tubing fashioned with hand tools.

Concrete Block Tables

by Bob Hess

I've described my 4x8' tables made of cinder blocks with steel plate and breadboard tops here in the past, floating on three or four inner tubes (from fork lift tires) or on tennis balls (an idea I got from Ken Haines). They all work fine if you can live with the excentricities of each type. I always rubbed the burrs off the cinder blocks before building the tables to decrease their stress when cinched together, and made the top of the blocks as flat as possible to minimize the thickness of filler material between them and the top.

Lay a piece of plastic film between the filler material and the top so you don't stick the top to the blocks for easier disassembly. I never used hexcel because the skin is too thin to adequately support heavy loads locally (in my opinion). A 4x8' optical breadboard with the threaded holes is best for a top as it's 3/16" skin is locally rigid, the surface is flat, and it can be moved by two men with piano dollies.

I like laying the cinder blocks out interlaced like a wall on its side, and running the threaded rods parallel to the short dimension of the table to minimize their length.


I thought I'd post some pics of old tables I described earlier in this thread. The one on the right above is the first I built in a bedroom of my apartment in East Palo Alto in 1982. The rods that squeeze the blocks together are running lengthwise in it and the the other as well. The table on the left has a steel top 3/16" thick, with cement patching material between it and the block surface. The bedroom window was covered with cardboard and black plastic. The lasers were in the other bedroom with their beams going through shuttered holes in the wall. I was on the ground floor slab in the corner of a three floor apartment building, and routinely did exposures up to around five minutes if I remember correctly with a 30mW HeNe laser.

The pic below shows the table I built in 2003 in a metal sculptor's studio in San Jose. The rods run across the table instead of lengthwise, and I used three legs instead of four. Same 4x8' Newport breadboard, which is now on its edge in the garage until I fix the garage. I fully supported the plywood base while laying out the cinder blocks to make them as flat as I could before squeezing them together.


Commercial Tables

Commercial Tables are the stiffest most versatile tables available. They come with tuned legs or active dampening. While there are by far the best they are also the most expensive.

Newport is one of the premiere manufactures.