DICHROIC GLASS
Dichroic (die-crow-ick) glass was discovered by bead-makers in the early
90's and has become a favorite. It has the ability to reflect intense
light,projecting vivid colors and a 3-D effect. A 16" square of the
glass can cost $100-$200, so it becomes crucial the artist knows how to work
with it.
Dichroic coatings are produced on a variety of glass materials. Originally
developed as interference filters in scientific measuring and correction
applications, they are a product of the technology called "thin film
physics".
The coatings are very thin, about 700 angstroms thick, and are generally
constructed of silicon and titanium oxides evenly shuffled into multiple
layers. These layers are applied by vacuum deposition and cause the glass
to become a partial mirror by allowing only a select narrow band of light
to transmit; other rays are rejected through reflection and absorption.
As the light rays transmit through the glass at a right angle they are
less effected by refraction than when passing at an extreme off axis angle
where they have to travel a greater distance through the coated material.
This greater distance causes a shift of color and when dichroic glass is
viewed at even slightly different angles, you will see differing colors.
Most photos of dichroic glass do not show the brilliance and beauty of
it . If you are at a gallery or craft show , look for items using this glass
and you will see the difference.
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