How it works
The
interference pattern that is recorded on the hologram can be considered as being a very thin layer
containing millions of tiny mirrors.
When light shines from one direction onto the hologram, all
these mirrors
reflect the light, each in its own direction.
Looking at the hologram from a certain
angle, you see
thousands of tiny reflections. Combined, these reflections
create an image.
Like a picture in a newspaper is
made out of dots of ink, a
hologram is built out of little dots of light.
If you now look at the hologram
from a different angle, the
dots of light you
were looking at will disappear. Instead,
other mirrors are now lighting up. Together they
form an
image that shows the object from a different angle.
So when you look at a hologram,
your eyes are always
seeing two different images. Because each eye is seeing the object
from the right perspective, your brain
is tricked - it makes you see a three-dimensional
object, instead of two slightly different flat images.
To complete the illusion, you can
also look at the object from different directions - the hologram always
shows the object
from the right angle.
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