From HoloWiki - A Holography FAQ
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There is a great deal of equipment available for use in holography. While a hologram can be made with very simple equipment, many holographers have $1000s invested into there labs. The most important piece of equipment is the Laser. It privides the coherent light source required for making a hologram.

In order to steer and shape the beam holographers use Mirrors, Lenses and Diffusers. More advanced holography is done with 'split beams'. This involves taking the laser beam in splitting it into two or more beams with a Beam Splitter.

A hologram is recorded on a medium. Silver Halide Film and Dichromated Gelatin Chemistry are the most common mediums for amature holographers and art holographs. Comercial holograms are usually Embossed Holograms or Polymer Film and Processes. Other exotic materials can record a holographic image. See Hologram Recording Materials. The stability of film is of the upmost importance to recording a hologram. Film Holders are designed to hold film stable to 1/2 wavelength of light for the entire exposure time (or better).

The polarization of a laser beam can be rotated with a Wave Plate and this can be quite useful in a large set up.

Every optic will contribute noise to the laser beam. Optics Aberrations, dust and fingerprints will leave a mark on the beam quality. In order to clean the beam a Spatial Filter is used.

All of the optics past the first Beam Splitter need to be held perfectly still. This is acoumplished by designing a Optical Bench and Optic Mounts that are very rigid and have no resonances.

The exposure time is calculated by using a Light Meter. Also the ratio of reference to object beam is measured with a Light Meter.

In order to adjust the exposure energy a Shutter is used to turn the beam on and off. A shutter can be as simple as a black card removed from the beam by hand or a computer controlled device

Fringe Lockers

Fringe Lockers

Beam Blocking

Beam Blockers

Neutral Density Filter

Neutral Density Filter