3D Representation
In Greek, “holos” means whole, and “gramma“means message.The definition of holography is a technique which render subject with complete dimensional fidelity.
Holography
Holography
The term ‘hologram’ can refer to both the encoded material and the resulting image.
The recordmeans the encoded material (Photosensitive plate) It is the recor-
ded interference pattern of constructive (intensity peaks) and destructive
(elimination) of the superimposed light-wavefronts (the electromagnetic field).
The resulting means image.
Left: A laser beam – the central element for creating a hologram. Right: Laser hologram projection of dragonfly by Martina Mrongovious, Hover 2004
Holograms are made using a LASER which produces a special kind of light in one pure colour. This light has the ability to
transfer information about an object’s surface characteristics and location in 3D space, to a light sensitive plate.
Down left: A plane wave passing through a barrier (traveling left to right), resulting in diffraction and interference Left: The basic set up for produ-
cing a ‘master’ laser transmission hologram
Middle: when hologram recording, it only record intensities (amplitude)
Right: The optical set up for a reflection hologram copy.
Formation of ImageThe essence: Two steps of image formation: First step
is to build a hologram, the object is transformed into a photographic record. Second is to
make reconstruction, which transform the hologram into the image. Hologram is the result of
interference. The signal means light diffracted by the object.
A Moiré pattern results from the interference of two similar undulating patterns, such as stripes The Moiré pattern shown above is from the superposition of a shifted wave-pattern (source Kafri 1990, p31)
Holography
types of display holograms
Paula Dawson To Absent Friends, 1989 | One of the laser transmission holograms, 150 x 95 cm.
Two perspectives showing the details of the scene from small holograms 4 x 5� (10.2 x 12.7 cm)
Up left: Iùaki Beguiristain, Telephone – Theydon Bois 2286, 2001 Down left: Holograms by Ana Maria Nicholson,
Two-colour (colour mix) reflection holograms from pulse laser masters (images courtesy of the artist)
Transmission holograms is formated where light shone th-
rough Reflection hologram is in which the hologram
reflects light
Right: Hans Bjelkhagen, BejeweledFish True colour
(panchromatic) reflection hologram
Holography
Michael Bleyenberg’s ‘light architecture’ Left: EyeFire Centre: AugenFeuer
Right: Design for a light façade roof
Computer generated ‘digital’ holography: With computer generated ‘digital’ holograms the fringe pattern
of each pixel is calculated and recorded into the hologram.In early systems these Hogels were noticeable
causing the surface of the hologram to look pixilated. Left and Centre: Geola Technologies Ltd Motor-
bikeRight: Zebra Imaging Downtown Seattle Holographic Print Computer generated digital hologram
Dot-matrix hologram printing is a technique of building up an image of diffractive ‘pixels’.Each area is recorded with
a particular geometry that diffracts light by a corresponding angle. The illuminating light is deflected into varying divergent
colour-spectrums. The image is a tiling of colours which means the images are very bright but do not have 3-d depth
information. Dot-matrix holograms have been used as a means of decorative ‘light architecture’.
Other application
Except those benefit our application in life. Art, there‘s also other usage that
Up left: Data storage Blu-ray Disc reach the limit of possible data density (due to the diffraction-limited size of the
writing beams. Down left: Security Bill, passport, credit card
Right: Art Fashion show, Custom Imaging