3 d holography projection technology

3D HOLOGRAPHY PROJECTION TECHNOLOGY
THE OXFORD COLLOG ENGG Page 1
CHAPTER 1
INTRODUCTION
Holography (from the Greek, whole + write) is the science of producing holograms.
It is an advanced form of photography that allows an image to be recorded in three dimensions.It
involves the use of a laser, interference, and diffraction, light intensity recording and suitable
illumination of the recording.
Dennis Gabor - Father of Holography and Holographic Technologies Dennis wrote a paper in
1948 that has become the foundation of modern Holography.
The most interesting thing about all this is that laser light had not even been invented
Yet, when he wrote his paper.
Dennis Gabor
Dennis Gabor is considered the Father of Holography and Holographic Technologies. Dennis
was born in Hungary in 1900. He started his study of physics at age 15 and eventually became a
Physicist in Britain. Dennis wrote a paper in 1948 that has become the foundation of modern
Holography. The most interesting thing about all this is that laser light had not even been
invented yet, when he wrote his paper. Thus his brilliant innovation and creative genius stands
out as one of the great inventors of the 20th Century. Later Dennis Gabor became a Professor at
Imperial College at the University of London in Applied Electron Physics. To learn more read a
brief Auto Biography; http://www.holophile.com/html/gabor.htm.

From 2D to 3D on a flat piece of cardboard was cool, but simply not what folks were
looking for.
Now then Hollywood 3D Movies were a big deal to movie goers and many remakes in
3D enjoyed another round at the Box Office. Similarly we see folks willing to re-watch their
favorite Action Movies again on the large screen under the din of a Giant IMAX Screen, as
it is the experience, not only the movie. Movies like Jaws III in 3D were very exciting and
drew large crowds to part take in the 3D experience.
Entertainment although the first commercial application and real use of Holography and
Holographic imaging is certainly not the be all end all of the technology.
Today we see Holographic Images on our ATM and Credit Cards or Microsoft Software as
proof of authenticity and thus preventing counterfeiting or piracy. Although some argue that
if the human reader of the credit card or holographic image on Microsoft Vista or Microsoft
Office 2007 does not know in advance what they are looking for then this might also be an
opportunity for thievery and counterfeited products to appear to be real. There are many
theories on privacy protection and Holographic Images.
Laser Light Shows have also given off the "Wow Factor" to audiences for years. Laser
Lights have also been incorporated into large events, inaugurations, rock concerts, 4th of
July celebrations and grand openings. In 1973 the public was introduced to the Griffith Park
Observatory in the World Famous LASERIUM (laser light shows). Of course within five
years was the use of a fully automated laser light show using computers and in Boston in
1977. Using computers and better accuracy the system could intersect beams of light to
perfection to produce letters or words in the sky.

CHAPTER 2
HOLOGRAPHY
Holography is a technique that enables a light field, which is generally the product of a
light source scattered off objects, to be recorded and later reconstructed when the original
light field is no longer present, due to the absence of the original objects. Holography can be
thought of as somewhat similar to sound recording, whereby a sound field created by
vibrating matter like musical instruments or vocal cords, is encoded in such a way that it
can be reproduced later, without the presence of the original vibrating matter.
Laser
Holograms are recorded using a flash of light that illuminates a scene and then imprints
on a recording medium, much in the way a photograph is recorded. In addition, however, part
of the light beam must be shone directly onto the recording medium - this second light beam
is known as the reference beam. A hologram requires a laser as the sole light source. Lasers
can be precisely controlled and have a fixed wavelength, unlike sunlight or light from
conventional sources, which contain many different wavelengths. To prevent external light
from interfering, holograms are usually taken in darkness, or in low level light of a different
color from the laser light used in making the hologram. Holography requires a specific
exposure time (just like photography), which can be controlled using a shutter, or by
electronically timing the laser.

Apparatus
A hologram can be made by shining part of the light beam directly onto the recording
medium, and the other part onto the object in such a way that some of the scattered light falls
onto the recording medium.
A more flexible arrangement for recording a hologram requires the laser beam to be aimed
through a series of elements that change it in different ways. The first element is a beam
splitter that divides the beam into two identical beams, each aimed in different directions:
One beam (known as the illumination or object beam) is spread using lenses and directed
onto the scene using mirrors. Some of the light scattered (reflected) from the scene then falls
The second beam (known as the reference beam) is also spread through the use of lenses,
but is directed so that it doesn't come in contact with the scene, and instead travels directly
Several different materials can be used as the recording medium. One of the most
common is a film very similar to photographic film (silver halide photo graphic emulsion),
but with a much higher concentration of light-reactive grains, making it capable of the much
higher resolution that holograms require. A layer of this recording medium (e.g. silver
halide) is attached to a transparent substrate, which is commonly glass, but may also be
plastic.

Holography vs. photography
Holography may be better understood via an examination of its differences from ordinary
photography:
A hologram represents a recording of information regarding the light that came from the
original scene as scattered in a range of directions rather than from only one direction, as in a
photograph. This allows the scene to be viewed from a range of different angles, as if it were
still present.
A photograph can be recorded using normal light sources (sunlight or electric lighting)
whereas a laser is required to record a hologram.
A lens is required in photography to record the image, whereas in holography, the light from
the object is scattered directly onto the recording medium.
A holographic recording requires a second light beam (the reference beam) to be directed
A photograph can be viewed in a wide range of lighting conditions, whereas holograms can
only be viewed with very specific forms of illumination. When a photograph is cut inhalf,
each piece shows half of the scene. When a hologram is cut in half, the whole scene can still
be seen in each piece. This is because, whereas each point in a photograph only represents
light scattered from a single point in the scene, each point on a holographic recording
includes information about light scattered from every point in the
scene. It can be thought of as viewing a street outside a house through a 4 ft. x 4 ft.window,
then through a 2 ft. x 2 ft. window. One can see all of the same things through the smaller
window (by moving the head to change the viewing angle), but the viewer can see more at
once through the 4 ft. window.
A photograph is a two-dimensional representation that can only reproduce a rudimentary
three-dimensional effect, whereas the reproduced viewing range of a hologram adds many
more depth perception cues that were present in the original scene. These cues are
recognized by the human brain and translated into the same perception of a three-
dimensional image as when the original scene might have been viewed.
A photograph clearly maps out the light field of the original scene. The developed
hologram's surface consists of a very fine, seemingly random pattern, which appears to bear
no relationship to the scene it recorded.

Chapter 3
PHYSICS OF HOLOGRAPH
For a better understanding of the process, it is necessary to understand interference
and diffraction. Interference occurs when one or more wave fronts are superimposed.
Diffraction occurs whenever a wave front encounters an object. The process of producing
a holographic reconstruction is explained below purely in terms of interference and
diffraction. It is somewhat simplified but is accurate enough to provide an understanding
of how the holographic process works.
Plane wave fronts
A diffraction grating is a structure with a repeating pattern. A simple example is a
metal plate with slits cut at regular intervals. A light wave incident on a grating is split
into several waves; the direction of these diffracted waves is determined by the grating
spacing and the wavelength of the light.
A simple hologram can be made by superimposing two plane waves from the same light
source on a holographic recording medium. The two waves interfere giving a straight
line fringe pattern whose intensity varies sinusoidal across the medium. The spacing of
the fringe pattern is determined by the angle between the two waves, and on the
wavelength of the light.
Point sources
If the recording medium is illuminated with a point source and a normally incident
plane wave, the resulting pattern is a sinusoidal zone plate which acts as a negative
Fresnel lens whose focal length is equal to the separation of the point source and the
recording plane.
When a plane wave front illuminates a negative lens, it is expanded into a wave which
appears to diverge from the focal point of the lens. Thus, when the recorded pattern is
illuminated with the original plane wave, some of the light is diffracted into a diverging
beam equivalent to the original plane wave; a holographic recording of the point source
has been created.
Sinusoidal zone plate

Complex objects
To record a hologram of a complex object, a laser beam is first split into two separate
beams of light. One beam illuminates the object, which then scatters light onto the
recording medium. According to diffraction theory, each point in the object acts as a
point source of light so the recording medium can be considered to be illuminated by a
set of point sources located at varying distances from the medium.
The second (reference) beam illuminates the recording medium directly. Each point
source wave interferes with the reference beam, giving rise to its own sinusoidal zone
plate in the recording medium. The resulting pattern is the sum of all these 'zone plates'
which combine to produce a random (speckle) pattern as in the photograph above.
Mathematical model
A single-frequency light wave can be modeled by a complex number U, which
represents the electric or magnetic field of the light wave. The amplitude and phase of
the light are represented by the absolute value and angle of the complex number. The
object and reference waves at any point in the holographic system are given by UO and
UR. The combined beam is given by UO + UR. The energy of the combined beams is
proportional to the square of magnitude of the combined waves as:
If a photographic plate is exposed to the two beams and then developed, its
transmittance, T, is proportional to the light energy that was incident on the plate and is
given by
, Where k is a constant.
When the developed plate is illuminated by the reference beam, the light transmitted
through the plate, UH is equal to the transmittance T multiplied by the reference beam
amplitude UR, giving
It can be seen that UH has four terms, each representing a light beam emerging from
the hologram. The first of these is proportional to UO.

CHAPTER 4
3D HOLOGRAPHY TECHNOLOGY
Holography is a diffraction-based coherent imaging technique in which a complex
three-dimensional object can be reproduced from a flat, two-dimensional screen with a
complex transparency representing amplitude and phase values. It is commonly agreed
that real-time holography is the ne plus ultra art and science of visualizing fast temporally
changing 3-D scenes. The integration of the real-time or electro-holographic principle
into display technology is one of the most promising but also challenging developments
for the future consumer display and TV market. Only holography allows the
reconstruction of natural-looking 3-D scenes, and therefore provides observers with a
completely comfortable viewing experience. A holo projector will use holographic
technology to project large-scale, high-resolution images onto a variety of different
surfaces, at different focal distances, from a relatively small-scale projection device. To
understand the technology used iconographic projection, we must understand the term
‘Hologram’, and the process of making and projecting holograms. Holography is a
technique that allows the light scattered from an object to be recorded and later
reconstructed.
Holograms
A hologram is a physical component or device that stores information about the
holographic image. For example a hologram can be a grating recorded on a piece of film.
It is especially useful to be able to record a full image of an object in a short exposure if
the object or space changes in time. Holos means “whole” and graphein means “writing”
Holography is a technique that is used to display objects or scenes in three dimensions.
These 3D images are called holograms. A photographic record produced by illuminating
the object with coherent light (as from a laser) and, without using lenses, exposing a film
to light reflected from this object and to a direct beam of coherent light. When
interference patterns on the film are illuminated by the coherent light a three-dimensional
image is produced.
Fig. 3.Fourier hologram used as a projector

Types of Holograms
A hologram is a recording in a two-or three-dimensional medium of the interference
pattern formed when a point source of light (the reference beam) of fixed wavelength
encounters light of the same fixed wavelength arriving from an object (the object beam).
When the hologram is illuminated by the reference beam alone, the diffraction pattern
recreates the wave fronts of light from the original object. Thus, the viewer sees an image
indistinguishable from the original object.
A.Reflection Holograms
The reflection hologram, in which a truly three-dimensional image is seen near its
surface, is the most common type shown in galleries. The hologram is illuminated by a
“spot” of white incandescent light, held at a specific angle and distance and located on the
viewer’s side of the hologram. Thus, the image consists of light reflected by the
hologram. Recently, these holograms have been made and displayed in colour their
images optically indistinguishable from the original objects. If a mirror is the object, the
holographic image of the mirror reflects white light
B. Transmission Holograms
The typical transmission hologram is viewed with laser light, usually of the same type
used to make the recording. This light is directed from behind the hologram and the
image is transmitted to the observer’s side. The virtual image can be very sharp and deep.
Furthermore, if an undiverged laser beam is directed backward (relative to the direction
of the reference beam) through the hologram, a real image can be projected onto a screen
located at the original position of the object.
C. Computer Generated Holograms
Computer Generated Holography (CGH) is the method of digitally generating
holographic interference patterns. A holographic image can be generated e.g. by digitally
computing a holographic interference pattern and printing it onto a mask or film for
subsequent illumination by suitable coherent light source. Alternatively, the holographic
image can be brought to life by a holographic 3Ddisplay (a display which operates on the
basis of interference of coherent light), bypassing the need of having to fabricate a
hardcopy of the holographic
interference pattern each time. Consequently, in recent times the term "computer
generated holography" is increasingly being used to denote the whole process chain of
synthetically preparing holographic light wavefronts suitable for observation

HOLOGRAM CLASSIFICATIONS AND RECORDING
There are three important properties of a hologram which are defined in this section. A
given hologram will have one or other of each of these three properties, e.g. amplitude
modulated thin transmission hologram, or a phase modulated, volume reflection hologram.
Amplitude and phase modulation holograms
An amplitude modulation hologram is one where the amplitude of light diffracted by the
hologram is proportional to the intensity of the recorded light. A straightforward example of
this is photographic emulsion on a transparent substrate. The emulsion is exposed to the
interference pattern, and is subsequently developed giving a transmittance which varies with
the intensity of the pattern - the lighter that fell on the plate at a given point, the darker the
developed plate at that point.
A phase hologram is made by changing either the thickness or the refractive index of the
material in proportion to the intensity of the holographic interference pattern. This is a phase
grating and it can be shown that when such a plate is illuminated by the original reference
beam, it reconstructs the original object wave front. The efficiency (i.e. the fraction of the
illuminated beam which is converted to reconstructed object beam) is greater for phase than
for amplitude modulated holograms.
Thin holograms and thick (volume) holograms
A thin hologram is one where the thickness of the recording medium is much less than the
spacing of the interference fringes which make up the holographic recording.
A thick or volume hologram is one where the thickness of the recording medium is greater
than the spacing of the interference pattern. The recorded hologram is now a three
dimensional structure, and it can be shown that incident light is diffracted by the grating only
at a particular angle, known as the Bragg angle. If the hologram is illuminated with a light
source incident at the original reference beam angle but a broad spectrum of wavelengths;
reconstruction occurs only at the wavelength of the original laser used. If the angle of
illumination is changed, reconstruction will occur at a different wavelength and the color of
the re-constructed scene changes. A volume hologram effectively acts as a color filter.
Transmission and reflection holograms
A transmission hologram is one where the object and reference beams are incident on the
recording medium from the same side. In practice, several more mirrors may be used to
direct the beams in the required directions.
Normally, transmission holograms can only be reconstructed using a laser or a quasi-
monochromatic source, but a particular type of transmission hologram, known as a rainbow.

Holographic recording media
The recording medium has to convert the original interference pattern into an optical element
that modifies either the amplitude or the phase of an incident light beam in proportion to the
intensity of the original light field.
The recording medium should be able to resolve fully all the fringes arising from interference
between object and reference beam. These fringe spacing can range from tens of micrometers
to less than one micrometer, i.e. spatial frequencies ranging from a few hundred to several
thousand cycles/mm, and ideally, the recording medium should have a response which is flat
over this range. If the response of the medium to these spatial frequencies is low, the
diffraction efficiency of the hologram will be poor, and a dim image will be obtained. Standard
photographic film has a very low or even zero response at the frequencies involved and cannot
be used to make a hologram - see, for example, Kodak's professional black and white film
whose resolution starts falling off at 20 lines/mm — it is unlikely that any reconstructed beam
could be obtained using this film.
If the response is not flat over the range of spatial frequencies in the interference pattern, then
the resolution of the reconstructed image may also be degraded.
The table below shows the principal materials used for holographic recording. Note that these
do not include the materials used in the mass replication of an existing hologram, which are
discussed in the next section. The resolution limit given in the table indicates the maximal
number of interference lines/mm of the gratings. The required exposure, expressed as milli
joules (mJ) of photon energy impacting the surface area, is for a long exposure time. Short
exposure times (less than 1/1000 of a second, such as with a pulsed laser) require much higher
exposure energies, due to reciprocity failure.
Propagating light away from the SLM and its effect on the observed pattern are shown in Fig.
We would like to add that Shannon recovery (i.e., recovery by low-pass filtering) is just one
possible recovery procedure. If we may use other recovery techniques than simple low-pass
filtering used for the Shannon sampling case, the Nyquist rate restriction above may not be
needed. Indeed reported that objects can still be fully recovered even from severely under
sampled (sampling below the Nyquist rate) Fresnel diffraction patterns. The condition for full
recovery from under sample diffraction patterns is not band limitedness, but other restrictions
like space-limitedness of the object pattern. Thus, if the diffraction pattern of a finite-size
object is sampled, we will observe replicas of the image of the object in the reconstruction
(higher diffraction orders) then, if the sampling rate is increased, replicas will move away
From each other and vice versa. Sampling rate can be de-creased until those replicas just
overlap. Then, by simply windowing in space we will get a fully recovered object function. As
a result, we can conclude that space-limited (thus not band limited) objects, which are quite
common in real-life applications, can still be fully recovered from their below Nyquist rate
samples. A generalization is the finite-support limitation at a Fresnel domain with a specific
parameter, as described by Gori, and this is equivalent to finite-support limitation in a
corresponding fractional Fourier domain.

Returning back to the Shannon recovery case, we start with the bandwidth limitation that
stems from the human visual system as mentioned earlier. We can apply the fore-going
discussion (Shannon recovery) to various practical cases to find out the required maximum
pixel period values. For example , for a stationary observer looking directly.

Copying and mass production
An existing hologram can be copied by embossing or optically. Most holographic
recordings (e.g. bleached silver halide, photo resist, and photopolymers) have surface relief
patterns which conform to the original illumination intensity. Embossing, which is similar
to the method used to stamp out plastic discs from a master in audio recording, involves
copying this surface relief pattern by impressing it onto another material.
The first step in the embossing process is to make a stamper by electrode position of
nickel on the relief image recorded on the photo resist or photo thermoplastic. When the
nickel layer is thick enough, it is separated from the master hologram and mounted on a
metal backing plate. The material used to make embossed copies consists of a polyester
base film, a resin separation layer and a thermoplastic film constituting the holographic
layer.
The embossing process can be carried out with a simple heated press. The bottom layer
of the duplicating film (the thermoplastic layer) is heated above its softening point and
pressed against the stamper, so that it takes up its shape. This shape is retained when the
film is cooled and removed from the press. In order to permit the viewing of embossed
holograms in reflection, an additional reflecting layer of aluminum is usually added on the
hologram recording layer. This method is particularly suited to mass production.
The first book to feature a hologram on the front cover was TheSkook (Warner Books,
1984) by JP Miller, featuring an illustration by Miller. That same year, "Telstar" by Ad
Infinitum became the first record with a hologram cover and National Geographic
published the first magazine with a hologram cover.[38] Embossed holograms are used
widely on credit cards, banknotes, and high value products for authentication purposes.[39]
It is possible to print holograms directly into steel using a sheet explosive charge to create
the required surface relief. The Royal Canadian Mint produces holographic gold and
silver coinage through a complex stamping process.

CHAPTER 5
RECONSTRUCTION OF HOLOGRAPH
When the hologram plate is illuminated by a laser beam identical to the reference beam
which was used to record the hologram, an exact reconstruction of the original object wave
front is obtained. An imaging system (an eye or a camera) located in the reconstructed
beam 'sees' exactly the same scene as it would have done when viewing the original. When
the lens is moved, the image changes in the same way as it would have done when the
object was in place. If several objects were present when the hologram was recorded, the
reconstructed objects move relative to one another, i.e. exhibit parallax, in the same way
as the original objects would have done. It was very common in the early days of
holography to use a chess board as the object and then take photographs at several different
angles using the reconstructed light to show how the relative positions of the chess pieces
appeared to change.
A holographic image can also be obtained using a different laser beam configuration to the
original recording object beam, but the reconstructed image will not match the original
exactly. When a laser is used to reconstruct the hologram, the image is speckled just as the
original image will have been. This can be a major drawback in viewing a hologram.
White light consists of light of a wide range of wavelengths. Normally, if a hologram is
illuminated by a white light source, each wavelength can be considered to generate its own
holographic reconstruction, and these will vary in size, angle, and distance. These will be
superimposed, and the summed image will wipe out any information about the original
scene, as if superimposing a set of photographs of the same object of different sizes and
orientations. However, a holographic image can be obtained using white light in specific
circumstances, e.g. with volume holograms and rainbow holograms. The white light source
used to view these holograms should always approximate to a point source, i.e. a spot light
or the sun.
White light reconstructions do not contain speckles.
Volume holograms
A volume hologram can give a reconstructed beam using white light, as the hologram
structure effectively filters out colors other than those equal to or very close to the color of
the laser used to make the hologram so that the reconstructed image will appear to be
approximately the same color as the laser light used to create the holographic recording.

Rainbow Methodology
In this method, parallax in the vertical plane is sacrificed to allow a bright well-defined
single color re-constructed image to be obtained using white light. The rainbow holography
recording process uses a horizontal slit to eliminate vertical parallax in the output image.
The viewer is then effectively viewing the holographic image through a narrow horizontal
slit. Horizontal parallax information is preserved but movement in the vertical direction
produces color rather than different vertical perspectives. Stereo sis and horizontal motion
parallax, two relatively powerful cues to depth, are preserved.
The holograms found on credit cards are examples of rainbow holograms. These are
technically transmission holograms mounted onto a reflective surface like a metalized
polyethylene terephthalate substrate commonly known as PET.
Rainbow hologram showing the change in color in the vertical direction

SBP AS A QUALITY METRIC FOR HOLOGRAPHIC
RECONSTRUCTIONS
We have already discussed the needed SBP on the SLM surface to have satisfactory quality
reconstructions. Information supported by the SLM as a holographic pattern on it is dispersed
to the free space away from the SLM by the modulated light. Now we want to understand how
that information is concentrated (or distributed) in space as a consequence of the diffraction
during the reconstruction. First, the reconstruction space corresponding to a single planar SLM
will be investigated.
As a plane wave is incident on a planar SLM perpendicularly, the light is diffracted and
propagated to form the reconstruction corresponding to the input image (pattern on the SLM)
within a limited angle due to the bandwidth of the system. The volume covered by the
diffracted beam may be regarded as the reconstruction space. Fig. 12 shows the quality metric
of the holographic reconstruction as a function of reconstruction position with respect to the
SLM, for a given SLM size. (Note that this figure does not show a diffraction pattern; instead,
it is just a pictorial representation of the variation of the profile of the quality metric as a
function of the distance from the SLM.) Quality metric in this analysis basically shows how
the ability of the SLM to concentrate information at a particular recon-traction position varies.
By the help of this quality metric, we can find the optimum location that has the potential to
yield maximum information concentration and therefore gives the highest quality local
reconstructions that the system can provide. Frequency band of the system is equivalent to the
solid angle in which the diffracted light propagates. Considering the distance of a focused
point on the optical axis by the hologram on the SLM as a variable, we see that the bandwidth
is restricted by the capabilities of the SLM until a certain distance, which we call z0, is
reached. The range 0 G z G z0 corresponds to the case where the band limited quadratic phase
pattern (the band-limited Fresnel hologram of a point) remains entirely in the SLM [see Fig.
13(a) and (b)]. Therefore, for 0 G z G z0, the bandwidth stays constant; however the area on
the SLM that is covered by the band limited quadratic phase function increases with z2 in this
range. Therefore, the quality metric, which is the SBP of the reconstruction, gets better
proportional to z2 in 0 G z G z0.
However, if z is increased beyond z0, portion of the related quadratic phase pattern on the
hologram plane will not fall onto the SLM [see Fig. 13(c)], and thus the sup-ported band will
start decreasing. Assuming that the SLM sits entirely within the enlarged quadratic phase
pattern for z > z1, it is easy to see that the 2-D frequency band will start decreasing with z2.
The range z0 G z G z1 will be the transition range.

Fig. .Quality metric of reconstruction by the hologram on the SLM as a function of distance of
the reconstructed image (white: high quality; black: low quality).

CHAPTER 6
RECENT RESULTS FROM BILKENT UNIVERSITY
Holographic displays have been investigated at Bilkent University, Ankara, Turkey, since
early 1990s . Recently, they used SLMs for such purposes and demon-started single and
multiple SLM holographic displays. They mostly use phase-only SLMs. For example, in a
study involving only one phase-only SLM , in-line phase holograms, which were calculated
byGerchberg–Saxton algorithm , were used to show that reconstructions that are larger than
the SLM size are feasible. In another system, three SLMs were used to generate color holo-
graphic reconstructions . Again the Gerchberg–Saxton algorithm was used to generate the in-
line phase holo-grams that were written on the SLMs. Three phase holo-grams were calculated
separately (for red, green, and blue channel) and loaded to the SLMs. Color light-emitting
diodes (LEDs) were used as light sources; all three reconstructions were combined to obtain a
color reconstruction. Yet another system generates and displays holograms in real time . The
phase-only holograms for the display were computed using a fast, approximation-based
algorithm called accurate compensated phase-added stereogram (ACPAS) , which was
implemented on graphics processing units (GPUs) to render the holograms at video rates.
LEDs were used as light sources for reconstructions that can be observed by naked eye. Fig. 1
shows the overall setup for the real-time color holographic display system and shows the
original color 3-D model, the computer reconstruction from the phase-only hologram, and the
optical reconstruction from the same hologram written on the SLM, respectively. They also
compared the quality of optical reconstructions obtained by using a laser and a LED as the
light source Fig2 shows . Even though LEDs have broader spectra than lasers, they conclude
that reconstructions using LEDs can be still satisfactory in quality. In a recent prototype, a
curved array of six phase-only SLMs was used to increase the field of view. As a consequence
of the achieved large field of view, the observer can look at the optical reconstruction
binocularly and see a real 3-D image floating in the space. Reconstructions can also be
observed from different angles without any discontinuity and with a larger horizontal parallax.
Fig. 3 shows the optical reconstructions of a pyramid recorded from different angles. The
ghost-like 3-D image (a real optical image) was positioned next to a similar physical object
located at the same depth, and the recording camera was focused to that plane; such a setup
shows the depth location of the reconstruction, as well as its quality of parallax and sharpness
by providing a similar physical object for comparison. The actual size of the base of the
pyramid is about 1 cm _ 1 cm, and its height is about 2 cm. The reconstruction (real image) is
about 50 cm in front of the SLM.

Overall setup: BEV beam expander; BSVnonpolarizedbeam splitter
Color holographic reconstruction a) Rigid color 3D object b) Computer reconstruction of 3D hologram
c) Optical reconstruction.

CHAPTER 7
APPLICATION
Military and SpaceApplications
 Pilot Training Augmenting the Real World
 Holographic Tech in Space
 Holographic Checkpoints
Holographic Technologies for Military Applications make a lot of sense really, especially if
you consider the potential for data visualization and table top holographic displays of the Net-
Centric Battle space in 4D. Spectral Imaging is already being used in medicine and life
sciences now and this is only a start to it's over all potential for military use.
In fact if you read some of the Future Fighting Force research papers and their References and
Works Cited and do just a little extra Background Reading of other Research Papers or peruse
the Media and surf some Internet Articles on the subject it should be relatively simple to see
that this is the future. Battle Simulation and Scenarios can be played in advance so that every
possible contingency can be calculated.
Holograms are a valuable tool on the battlefield itself also, consider Holographic Decoys and
Deception Applications - deception tactics are extremely important in wartime. Better yet, just
the fact that you have these technologies makes the enemy second guess you and hesitates and
the way that wars are fought now at light speed, that is an extreme advantage.
Many new soldiers are not quite prepared for the reality of war and the gruesome sights they
will see, which often leave psychological and emotional scares. With Holographic Imaging the
soldier can be toughened up prior to battle using hologram Virtual Reality Training and Mind
Conditioning equipment.
Tele-Presence in Command and Control Communication also will be a major military
application of holographic technology. Instead of mere, voice or video, specially coded
holographic communication will rule the day. Military application and holographic
technologies make sense for a lot of reasons and the one I like best is that we can protect the
American People using Holograms as one more tool in our arsenal.

Holographic Checkpointfor Military
One of the most dangerous jobs right now in the United States Military is guarding the borders of
Iraq. Your life expectancy if you do not stay „heads up‟ is very low. It requires super human
concentration and intuition, none of which is very easy when the weather is not cooperating,
either too hot, too cold or dust storms. The soldier must be very alert at all times, follow
protocol and you just never know when someone is out to do you in. Each day the soldiers
live in fear that their number could be up in an instant, not knowing if it will happen to them,
a friend of theirs or if today is, that day.
I propose a new concept using the up and coming future advances in Holographic
Technologies, which are getting closer to becoming reality we may soon be able to design a
Holographic Soldier to stand at the check point so if someone tries to run him over, they can
try all they want as you cannot kill a ghost or a mirage which is not there at all.
I propose we put holographic projectors in the Humvees to display the 3D or 4D image of the
Soldier in Virtual Reality. The system will run off the Humvee’s extra alternator for juice and
will not need the power grid, the Humvee will can drive up point it away from the road, park
the vehicle, turn it on and the Border Patrol Soldier will do its job, along with sensors and
cameras without risking his life. If there is a problem the Soldiers away from the area will
open fire from a short distance away out of any blast range in case there is a car bomb.

Holographic TechEntertainment
Holography in Entertainment has been pushed beyond its actual capabilities in the past, although the
current technology is rapidly approaching the Futurism of the Sic Fi past. Next will come the Video
Gaming in the Living Room, IMAX Style High-Tech Theatres and Extreme Sports Holograms as our
Invisible Friends Come Alive. From Cartoons to Reality and you can do anything you want in a
dream world with Holographic Technologies of the Future and yet we are forewarned of the Dangers
of Blurring Reality as Hollywood Goes all the way with High-Tech Holography.
This potential problem should be easy to see in the future for instance there is the darker side to such
things - Holographic Adult Entertainment, which ought to bring in quite a few dollars to the infamous
porn industry. And if that is not enough, well just wait until all the Entertainment Turns into
Advertising? Nevertheless folks want their entertainment and they are willing to pay for that desire.
We know there is always big money available for Research and Development of any technology that
has a killer entertainment application. From Xbox to the new iPods, we have seen this technology
trend for decades.

Video Gaming Living Room
What will your living room look like in 2020 with all the new nifty high-tech entertainment devices
available in the future? Already we see the flat panel large screen Television monitors and the new
Xbox 360 is certainly incredible too. Then there is surround a sound and also little ear buds for
perfect sound with little tiny electronic gadgets like the iPod.
Is it possible that in the future they will add holographic projection to these devices too? A literal
virtual reality setting in your own living room; that is to say the future of Holographic Virtual Reality
in your living room may appear more real life than the real world. And probably more exciting,
challenging, entertaining and fun as well?
This does bring up a good point about the issues with visionaries and technology, as we watch the
battle for the consumer electronics surpass the average consumer’s imagination and warp your real
world into a rather augmented reality. Many high-tech engineers have lots of VR thoughts, some
military with regard to simulation, Mars CAVE, automobile and truck simulators for training too.
Particularly of interest along the concept and theme and with regard to holographic VR, turning
one's living room into your own VR gamming or learning experience; you will not have to go very
far on any Internet search engine to see my point and a glimpse into the possible Holographic
Virtual Reality Living Room. .

Teaching and Training
Holographic Technology - Teaching and Training
Holographic Projection technologies are coming soon and the scientists and researchers are being
funded by smart entrepreneurs who see the benefits and potential applications. In fact imagine a
solution to the problem in grade school with too many kids and not enough teachers? Well with
holographic technologies the Virtual Teacher's Aids Come Alive.
Of course such Virtual AI Holographic Assistants can come in many forms such as One on One
with VR Holographic Avatars or for use in training of adults in real life simulation. A college class
may have a guest speaker and sign up at the Guest Speaker's Bureau and a virtual holographic
speaker ought to be a little bit cheaper. The question is if the speaker is Real or Memorex? What
about your regular college teacher? Is Your Professor Real?
Holographic Technologies will also be great for Sport Technique Coaching and Training. In fact
nearly all training in Virtual Reality Simulation will go Holographic with Holographic
Demonstrations locally or thru Long Distance eLearning initiatives where the Holographic
Images are broadcast over the Internet.

Corporate Meetings Without Travel
The Ultimate in CorporateOnline Holographic
3D Power Point Presentations.
Virtual Reality and Computerized Projection Video Conferences with Holographic Images or
Spectral Imagining Technologies are an obvious first adopter industry use. Indeed, these
technologies already exist and those who use them swear by them.
In the future there will be VR Virtual Reality meetings using computerized holographic projection, as
these technologies are all currently available and becoming more robust and soon will be mass
marketed. Give it 3-5 years, 10 at most and we will see some pretty wide spread use of these
technologies. The first uses will be for entertainment; Virtual Lovers, Living Room 3D Gaming and
meetings with fellow bloggers and Internet Friend.
The costs at first will not be cheap and the bandwidth requirements substantial so not everyone will
have them right away. Call the challenge the "DBD" or Digital Bandwidth Divide. Well we will
need the increased speeds for future holographic meetings, video on the go and all sorts of
communication devices too. I have some ideas to be able to read the information much faster using
shapes as symbols for words rather than one's and zero's.

CHAPTER 8
FUTURE OF HOLOGRAPHIC POJECTION
3D holographic projection technology clearly has a big future ahead. As this audio visual display
continues to get high profile credibility, we are likely to see more companies advertising their
products or marketing their business in this way. Whether it be large scale, big budget product
launches or smaller retail POS systems, they are likely to become a common feature in the
advertising world.
The holographic projectors that are under development will be able to be much smaller and
portable than image projectors that rely on conventional, incoherent light beams. Ultimately,
holographic projectors may become sufficiently small to be incorporated into future generation cell
phones. Holographic techniques are being used for three-dimensional (3-D) rendering of medical
pictures including MRI and CT pictures. Medical holotechnology imaging can enable doctors to test
the insertion of medical instruments into an artificially constructed, three-dimensional version of the
surgical field before the operation. An array of micro- mirrors, whose movements are controlled by
computer, may be used to divide and focus an array of laser beams to make moving, three-
dimensional holographic pictures of internal anatomic features.
Holographic projectors will be able to render sharp projected images from relatively small
projection devices (e.g. cell-phones) because they do not require high intensity, high-temperature
light sources. Investigators at companies and universities are working toward applied science that
could make television with holographic projections (holovisions) that can project moving, three-
dimensional pictures outside of the screen. Genuine holographic motion picture science lets people
see travelling, three-dimensional images absent special glasses. One means of creating animated
holotechnology images is to send laser light by means of a lithium niobate waveguide covered by
piezoelectric material. A modulator converts video impulses into vibrations of the piezoelectric
material that, in turn, alters the configuration of the light beam going through it. When this ray is
shone into a translucent volume, it creates a 3D travelling image. Two and three dimensional
interference patterns presents some alternative perspectives.
A holographic memory device that can store as much as five gigabytes could replace flash memory
for many usages. It would be a boon to handheld machines like PDAs and smart phones. Next
generation smart phones may use holotechnology applied science for data storage and display
projection. For memory, holographic information recording and playback could significantly increase
the memory capacity of phones. For display, holotechnology projection can show images,
unconstrained by the tiny size of a handheld device. The idea of watching television on one's
cellphone is in vogue now, but who wants to watch TV on a 2" screen? If it were possible to project a
large picture from a cellphone onto a nearby wall, that would transform the use of cellphones for
visual media. Also, storing data three-dimensionally with holographic storage has interesting notes on
this holotechnology topic.
In the areas of telecommunications and instruction, remote conferencing and distance education
technologies featuring 2D screen pictures will evolve into three-dimensional, engaging holographic
projection systems. Holographic applied science is, even now, being used for "HoloCells"
(holographic cell phones that record and play three-dimensional, real time pictures of the

communicating parties that may be viewed from different angles). The site three-dimensional medical
imaging also provides information on these topics.
A holographic memory device that can hold up to several gigabytes could compete with flash
memory for several usages. It would be a boon to handheld machines especially smart phones and
PDAs. Future versions of smart phones may use holotechnology applied science for both memory and
display functions. For memory, holotechnology information recording and playback can greatly
increase the memory capacity of phones. For display, holographic projection can show pictures that
are not constrained by the small size of a mobile device. The prospect of watching TV on a mobile
phone is in vogue now, but who wants to watch television on a 3" diagonal screen? If it were possible
to project a large picture from one's cellphone onto the wall nearby, that would transform the use of
cellphones for visual media. Linked page media for holographic data storage also has different
information on this topic.
Holographic applied science can also create new methods for three- dimensional visual contact
from computing systems to human beings. This starts with screen displays with improved 3D
projection qualities and then improves to mid-air, three- dimensional computer projections that do not
require a screen. Similar holotech coverage at holographic technology and navigation may be of
interest.
Design is central to applied science, new product development and model building, building design
and construction, pharmaceuticals, biological, and Nano pharmacology, biochemistry and modeling at
the molecular scale, biomedical technology and prostheses, the apparel industry, the fine arts, and
other areas as well. Holotech applied science can help design for: manipulation of 3D models of
molecules or biological structures; assembling electronics; and other design-related tasks. Linked
page 3D imaging using micro-mirror arrays also deals with these technologies.
At the present time, DVDs and CDs are still the main formats for mobile information storage
media for music, video, and information. These traditional data storage media store information as
distinct bits on the surface of the recording medium and the medium should be spun around to
recover the information. The price of saving information is dropping but the need, however, for
long-term information storage has been increasing even more promptly. Holotech information
storage opens possibilities for saving information at much higher densities than CDs and DVDs by
storing information three- dimensionally throughout the thickness of the recordable media. Visit
also holographic data storage process .
.
The Japanese Government is pushing huge financial and technical weight into the development of
three-dimensional, virtual-reality television, and the country's Communications Ministry is aiming at
having such technology available by 2020. Peyghambarian said there are no major sponsors of the
technology at present, but as the breakthroughs continued, he hopes that will change.

CHAPTER 9
NON OPTICAL HOLOGRAPHY
In principle, it is possible to make a hologram for any wave.
Electron holography is the application of holography techniques to electron waves rather than light
waves. Electron holography was invented by Dennis Gabor to improve the resolution and avoid the
aberrations of the transmission electron microscope. Today it is commonly used to study electric and
magnetic fields in thin films, as magnetic and electric fields can shift the phase of the interfering
wave passing through the sample.The principle of electron holography can also be applied to
interference lithography.
Acoustic holography is a method used to estimate the sound field near a source by measuring
acoustic parameters away from the source via an array of pressure and/or particle velocity
transducers. Measuring techniques included within acoustic holography are becoming increasingly
popular in various fields, most notably those of transportation, vehicle and aircraft design, and NVH.
The general idea of acoustic holography has led to different versions such as near-field acoustic
holography (NAH) and statistically optimal near-field acoustic holography (SONAH). For audio
rendition, the wave field synthesis is the most related procedure.
Atomic holography has evolved out of the development of the basic elements of atom optics.
With the Fresnel diffraction lens and atomic mirrors atomic holography follows a natural step in the
development of the physics (and applications) of atomic beams. Recent developments including
atomic mirrors and especially ridged mirrors have provided the tools necessary for the creation of
atomic holograms although such holograms have not yet been commercialized.

CHAPTER 10
THINGS OFTEN CONFUSED WITH HOLOGRAPHY
Effects produced by lenticular printing, the Pepper's Ghost illusion (or modern variants such as
the Musion Eyeliner), tomography and volumetric displays are often confused with holograms.
The Pepper's ghost technique, being the easiest to implement of these methods, is most prevalent
in 3D displays that claim to be (or are referred to as) "holographic". While the original illusion, used
in theatre, involved actual physical objects and persons, located offstage, modern variants replace the
source object with a digital screen, which displays imagery generated with 3D computer graphics to
provide the necessary depth cues. Reflection, which seems to float mid-air, is still flat; however, thus
less realistic than if an actual 3D object was being reflected.
Examples of this digital version of Pepper's ghost illusion include the Gorillaz performances in
the 2005 MTV Europe Music Awards and the 48th Grammy Awards; and Tupac Shakur's virtual
performance at Coachella Valley Music and Arts Festival in 2012, rapping alongside Snoop Dogg
during his set with Dr. Dre.
During the 2008 American presidential election, CNNdebuted its tomograms to "beam in"
correspondents including musician will.i.am as "holograms".
An even simpler illusion can be created by rear-projecting realistic images into semi-transparent
screens. The rear projection is necessary because otherwise the semi-transparency of the screen
would allow the background to be illuminated by the projection, which would break the illusion.
Krypton Future Media, a music software company that produced Hatsune Miku, one of many
Vocaloid singing synthesizer applications, has produced concerts that have Miku, along with other
Crypton Vocaloids, performing on stage as "holographic" characters. These concerts use rear
projection onto a semi-transparent DILAD screen to achieve its "holographic"
In 2011, in Beijing, apparel company Burberry produced the "Burberry Prorsum Autumn/Winter
2011 Hologram Runway Show", which included life size 2-D projections of models. The company's
own video. Shows several centered and off-center shots of the main 2-dimensional projection screen,
the latter revealing the flatness of the virtual models. The claim that holography was used was
reported as fact in the trade media.

CHAPTER 11
CONCLUSION
Digital holographic video displays are strong candidates for rendering ghost-like Btrue 3-D motion
images. Interest in this technology is increasing among the research community. Many laboratories
have already reported different designs with promising results. Most of these designs are based on
SLMs; SLMs with different capabilities and specifications have been used. Therefore, it is important
to understand the limitations of such devices, and their effects on the resultant 3-D images. The two
major parameters are the size and the resolution; therefore, the SBP is a suitable metric to assess a
digital holographic device.
Reasonable sizes and resolutions seem to be sufficient for a stationary observer with no lateral or
rotational motion. However, the needed SLM size and pixel density quickly increase beyond the
capabilities of today’s electronic technology when such motion is allowed as in a natural viewing
environment. An alternative is to arrange planar SLMs on a curved mount to relieve the requirement
of small and high-density pixels.
Since the holograms are quite robust to quantization errors, and since frame refresh rates are
satisfactory for continuous perception, the focus of research is rather on designing digital holographic
display sets, which can effectively support more freedom in lateral and rotational motion of the
observer while providing satisfactory quality 3-D images

References and
Works
BackgroundReading
1.) Dr. Bjelkhagen, Hans I. Advances in Display Holography. Proceedings of the 7th
International Symposium on Display Holography. 2006.
2.) Winslow, Lance. Hover boards of the Future. Palm Desert, CA. Online Think Tank
Publishing, 2007.
3.) Winslow, Lance. Truck Technologies of the Future. Palm Desert, CA. Online Think
Tank Publishing, 2007.
4)Apple Progressing with 3D Holographic Projection Technology (The Macintosh News Network]
http://www.aboutprojectors.com/ 2008.
5)Holographic projection technology creates impact - An Activ8-3D product story. Edited by the Marketing
week Marketplace editorial team Sep 2, 2009
6) Cisco Telepresence 'On-Stage' Holographic Video Conferencing.
http://www.eyeliner3d.com/cisco_telepresence_holographic_video_conferencing.html

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