About
Holography
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What is a
Display Hologram?
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What
Color is a Hologram?
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A display hologram is a 3D
print that has been recorded using laser light onto a specialized
photographic plate or film resulting in a true three-dimensional image of
the original subject. Unlike other 3-D techniques, holography allows the
creation of true full-parallax 3-D images of astonishing detail.
The holograms depicted in
this web-site are produced as two principal types of holograms:
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Transmission Holograms
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Reflection Holograms.
Simply speaking
transmission holograms are viewed by the transmission of light as in the
viewing of a photographic slide. Reflection holograms are viewed by the
reflection of light as in the viewing of a normal photo (see below).
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Reflection
holograms produced by the studio described in this web-site are generally
monochromatic. The hologram color may be adjusted chemically from
blue right through to red. The spread of colors may also be adjusted using
chemistry giving a variety of pleasing visual effects.
Transmission
Holograms produced by the systems described in this web-site are what are
known as Rainbow Holograms. The perceived color of a rainbow hologram
changes from red to blue as the height of the viewer's head changes.
Both
transmission and rainbow holograms may be generated by analog or digital
origination from our holography studio.
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Is
Special Lighting Required for Viewing Holograms?
No - optimal viewing is obtained
by simply illuminating the final display hologram with a standard halogen
spot lamp.
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Pictures showing replay of a
reflection (left) and transmission (right) hologram employing a common
halogen spotlight
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FAQs About
Holography & Forth Dimension Holography Studios
What are holograms? Holograms (hlgrm, n.; [holo= whole
& gram= picture]) are true three
dimensional images recorded photographically using the special coherent properties of laser
light.
How long have holograms been around? The theory of holography was conceptualized
by the
Hungarian scientist Dennis Gabor in 1947 but it was not until the 1960's and the invention
of the
L.A.S.E.R. (Light Amplification by Stimulated Emission of Radiation) that the first holograms were
produced. In 1971 Dr. Gabor received the Nobel Prize in physics for his invention. Considering its
cousin photography is over 150 years old holography is still indeed in its infancy.
Pulsed holography
is still in the womb & the cutting edge for display holography.
What is the difference between a analog & digital hologram? To
produce an analog hologram
we use actual real 3/D subject matter (people, animals, models, etc.). To produce a
digital hologram
we use digital computer files & "write" them as a master hologram. Analog
holograms have much
greater resolution but must be recorded on a 1:1 recording ratio from the actual subject matter.
Digital
holograms offer much less detail but can be done of anything that can be conceived of in the
computer environment.
What is the largest size holograms you can produce? Currently the
largest size holograms we
produce is 3.2x4.5 feet. By tiling these holograms together, still larger holograms can be
produced.
For portraiture, our normal sizes are 12x16 & 16x24 inches.
I thought objects had to be very still for holograms- How are you able to
record people &
animals? For normal lasers this is true but with our proprietary pulsed system the
laser "fires" its
light energy in a duration of only 20 nanoseconds- that is 20/1,000,000,000
(billionths) of a second!
Essentially nothing can move in
this time except light itself.
How long does it take to produce a hologram? That depends. For
large scale display holograms
used in advertising & commerce the general time frame is from 6-8 weeks. For
commissioned
portraiture we usually have the holograms completed for our clients the same
or next day. Depending
on quantity, high-volume runs are usually finished in 4-6 weeks.
Return
to Forth Dimension Holography Studio