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and fellows meeting May, 1974.
Ultrasonic transmission holography of the
eye. EDWIN E. BOLDREY, DAVID R. HOL-
BROOKE, AND VICTOR RICHARDS.
Ocular ultrasonic transmission holography of the
eye using equipment capable of real-time imaging
has not previously been described. A method using
pulsed, ultrasound focused on an air/liquid inter-
face is used to demonstrate normal ocular struc-
tures including lens, optic nerve, and sclcra. Intra-
ocular foreign bodies imaged include radiopaque
and nonradiopaque materials. A limit of resolution
of at least I mm. is demonstrated.
Holography is a method of recording and re-
producing life-like images of an object. A hologram
is formed when light or other energy illuminating
a scene is combined with the energy of a second
identical but unaffected energy field. The combina-
tion of these two beams—the illuminating and
reference beams—forms an interference pattern
which can be recorded on film. When this film is
illuminated with the reference beam, the inter-
ference pattern formed by the combination of the
original two beams is interrogated, resulting in
an image of the original illuminated field. This
image is identical in all respects to the original
field, containing both amplitude and phase infor-
mation. Unlike ordinary photography, which
records only amplitude information, a hologram
is a true perspective image allowing true three-
The basic principles of holography were first
described by Cabor in 1948,-' but the first laser
optical holograms were not reported until 1962.:|
Optical holographic imaging of a model eye was
first done in 1966,' but not until 1970 did Calkins
LIQUID SURFACE HOLOGRAM