Rami Arieli: "The
Laser Adventure" Chapter 10 Section 5, page 3
Silver Halide Emulsion
Silver Halide emulsions are the
most well known medium for recording holograms is an emulsion of Silver
Halide.
These photographic materials are the most sensitive holographic recording
materials.
Silver Halide emulsion is sensitive over the entire visible spectrum,
and even in the near infra red (NIR) - Nd YAG laser wavelength.
Exposure to light generate Latent
Image.
Developing the emotion creates visible pattern by generating
Silver grains around the exposed Silver atoms.
The result is an amplitude
hologram.
Bleaching convert
the metallic Silver into dielectric Silver salts, thus creating phase
hologram.
The Silver halide emulsion can be coated on either glass
or film.
Glass plate
is more stable and easy to use, but is much more expensive.
Its resolution is about 3,000 lines per mm, and the emulsion
is sensitive to visible light.
The disadvantages of this photographic
film:
-
The requirement of developing the film in a dark room, with the use of
chemicals.
-
The silver crystals on the developed film cause scattering.