physics assignment 2.docx

8/19/2019 physics assignment 2.docx

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Applications of Polaroids

Polaroids polarize light. A number of needle shaped crystals quinine iodosulphate with theiraxes parallel to one another are packed between two sheets of plastic. This arrangementserves as the polaroids.

The important uses are:

• These reduce excess glare and hence sun glasses are tted with Polaroid sheets.

• These are also used to reduce headlight glare of cars.

• They are used to improve color contrast in old oil paintings.• These are useful in !"# motion pictures i.e.$ holography.

• %ind shields of automobiles are also made of Polaroid sheets.

Uses of Polaroids

Polaroids polarize light. A number of needle shaped crystals quinine iodosulphate with their

axes parallel to one another are packed between two sheets of plastic. This arrangement

serves as the polaroids. The important uses are:

• These reduce excess glare and hence sun glasses are tted with Polaroid sheets.

• These are also used to reduce headlight glare of cars.

• They are used to improve color contrast in old oil paintings.

• These are useful in !"# motion pictures i.e.$ holography.

• %ind shields of automobiles are also made of Polaroid sheets.

Polarizing sheets are used in liquid crystal displays$ optical microscopes and sunglasses. &ince

Polaroid sheet is dichroic$ it will absorb impinging light of one plane of polarization$ so

sunglasses will reduce the partially polarized light re'ected from level surfaces such as

windows and sheets of water$ for example. They are also used to examine for chain

orientation in transparent plastic products made from polystyrene or polycarbonate.

The intensity of light passing through a Polaroid polarizer is described by (alus) law.

Uses of polaroid

*. Polaroids are used in the laboratory to produce and analyse plane polarized light+. Polaroids are widely used as polarizing sun glasses!. They are used to eliminate the head light glare in motor cars.,. They are used to improve colour contrasts in old oil paintings.-. Polaroid lms are used to produce three"dimensonal moving pictures.. They are used as glass windows in trains and aeroplanes to control the intensity

of light. /n aeroplane one polaroid is xed outside the window while the other is

tted inside which can be rotated. The intensity of light can be ad0usted by

rotating the inner polaroid.

1. Aerial pictures may be taken from slightly di2erent angles and when viewedthrough polaroids give a better perception of depth.

3. /n calculators and watches$ letters and numbers are formed by liquid crystal

display456#7 through polarisation of light.8. Polarization is also used to study size and shape of molecules.

http://en.wikipedia.org/wiki/Liquid_crystal_displayhttp://en.wikipedia.org/wiki/Microscopehttp://en.wikipedia.org/wiki/Sunglasseshttp://en.wikipedia.org/wiki/Polystyrenehttp://en.wikipedia.org/wiki/Polycarbonatehttp://en.wikipedia.org/wiki/Polarizer#Malus.27_law_and_other_propertieshttp://en.wikipedia.org/wiki/Microscopehttp://en.wikipedia.org/wiki/Sunglasseshttp://en.wikipedia.org/wiki/Polystyrenehttp://en.wikipedia.org/wiki/Polycarbonatehttp://en.wikipedia.org/wiki/Polarizer#Malus.27_law_and_other_propertieshttp://en.wikipedia.org/wiki/Liquid_crystal_display


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Applications of Ultrasonics

9omogenizing #ispersing and #eagglomeration

mulsifying %et"(illing and ;rinding

#isintegration

6ell xtraction 9ot %ater #isinfection

&onochemistry

Transesterication 4ltrasonic homogenizing is very e?cient for the reduction of soft and hard particles.

9ielscher produces ultrasonic devices for the homogenization of any liquid volume for batch

or inline processing. 5aboratory ultrasonic devices can be used for volumes from *.-m5 to

approx. +5. >ltrasonic industrial devices are used for the process development and production

of batches from @.- to approx +@@@5 or 'ow rates from @.*5 to +@m per hour.

Ultrasonic Dispersing and Deagglomeration

The dispersing and deagglomeration of solids into liquids is an important application of

ultrasonic devices. >ltrasonic cavitation generates high shear forces that break particle

agglomerates into single dispersed particles. The mixing of powders into liquids is a common

step in the formulation of various products$ such as paint$ ink$ shampoo$ beverages$ or

polishing media. The individual particles are held together by attraction forces of various

physical and chemical nature$ including van der %aals forces and liquid surface tension. The

attraction forces must be overcome on order to deagglomerate and disperse the particles into

liquid media. Bor the dispersing and deagglomeration of powders in liquids$ high intensity

ultrasonication is an interesting alternative to high pressure homogenizers and rotor"stator"

mixers.

Ultrasonic Emulsifying

A wide range of intermediate and consumer products$ such as cosmetics and skin lotions$

pharmaceutical ointments$ varnishes$ paints and lubricants and fuels are based wholly or in

part of emulsions. mulsions are dispersions of two or more immiscible liquids. 9ighly

intensive ultrasound supplies the power needed to disperse a liquid phase 4dispersed phase7

in small droplets in a second phase 4continuous phase7. /n the dispersing zone$ imploding

cavitation bubbles cause intensive shock waves in the surrounding liquid and result in the

formation of liquid 0ets of high liquid velocity. At appropriate energy density levels$ ultrasound

can well achieve a mean droplet sizes below * micron 4micro"emulsion7.

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Ultrasonic Wet-Milling and Grinding

>ltrasonication is an e?cient means for the wet"milling and micro"grinding of particles. /n

particular for the manufacturing of superne"size slurries$ ultrasound has many advantages$

when compared with common size reduction equipment$ such as: colloid mills 4e.g. ball mills$

bead mills7$ disc mills or 0et mills. >ltrasonication allows for the processing of high"

concentration and high"viscosity slurries C therefore reducing the volume to be processed.

>ltrasonic milling is suitable for processing micron"size and nano"size materials$ such asceramics$ alumina trihydrate$ barium sulphate$ calcium carbonate and metal oxides.

Ultrasonic Cell Disintegration

>ltrasonic treatment can disintegrate brous$ cellulosic material into ne particles and break

the walls of the cell structure. This releases more of the intra"cellular material$ such as starch

or sugar into the liquid. /n addition to that the cell wall material is being broken into small

debris.

This e2ect can be used for fermentation$ digestion and other conversion processes of organic

matter. After milling and grinding$ ultrasonication makes more of the intra"cellular material

e.g. starch as well as the cell wall debris available to the enzymes that convert starch into

sugars. /t does also increase the surface area exposed to the enzymes during liquefaction or

saccharication. This does typically increase the speed and yield of yeast fermentation and

other conversion processes$ e.g. to boost the ethanol production from biomass.

Ultrasonic Cell Extraction

The extraction of enzymes and proteins stored in cells and subcellular particles is an e2ective

application of high"intensity ultrasound$ as the extraction of organic compounds contained

within the body of plants and seeds by a solvent can be signicantly improved. >ltrasound

has a potential benet in the extraction and isolation of novel potentially bioactive

components$ e.g. from non"utilized by"product streams formed in current processes.

Continuous Disinfection of Hot Water ystems

To ght the dangerous 5egionella bacteria in hot water systems and secure a safer showering

environment the;ruenbeck company has developed the ;DE"breakF system. This system

uses 9ielscher ultrasonic technology in combination with >G"6 light.

onoc!emical Application of Ultrasonics

&onochemistry is the application of ultrasound to chemical reactions and processes. The

mechanism causing sonochemical e2ects in liquids is the phenomenon of acoustic cavitation.

The sonochemical e2ects to chemical reactions and processes include increase in reaction

speed and=or output$ more e?cient energy usage$ performance improvement of phase

transfer catalysts$ activation of metals and solids or increase in the reactivity of reagents or

catalysts.

Ultrasonic "ransesteri#cation of $il to %iodiesel

>ltrasonication increases the chemical reaction speed and yield of the transesterication of

vegetable oils and animal fats into biodiesel. This allows changing the production from batch

processing to continuous 'ow processing and it reduces investment and operational costs.

The manufacturing of biodiesel from vegetable oils or animal fats$ involves the base"catalyzed

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transesterication of fatty acids with methanol or ethanol to give the corresponding methyl

esters or ethyl esters. >ltrasonication can achieve a biodiesel yield in excess of 88H.

>ltrasound reduces the processing time and the separation time signicantly.

Ultrasonic Degassing of &i'uids

#egassing of liquids is an interesting application of ultrasonic devices. /n this case the

ultrasound removes small suspended gas"bubbles from the liquid and reduces the level of dissolved gas below the natural equilibrium level.

onication of %ottles and Cans for &ea( Detection

>ltrasound is being used in bottling and lling machines to check cans and bottles for leaks.

The instantaneous release of carbon dioxide is the decisive e2ect of ultrasonic leakage tests

of containers lled with carbonated beverages.

Ultrasonic Wire) Ca*le and trip Cleaning

>ltrasonic cleaning is an environmentally friendly alternative for the cleaning of continuous

materials$ such as wire and cable$ tape or tubes. The e2ect of the cavitation generated by the

ultrasonic power removes lubrication residues like oil or grease$ soaps$ stearates or dust.

Applications of Ultrasonic Sound

Sounds in the range 20-100kHz are commonly used for communication and navigationby bats, dolphins, and some other species. uch higher fre!uencies, in the range 1-20

Hz, are used for medical ultrasound. Such sounds are produced by ultrasonic

transducers. " #ide variety of medical diagnostic applications use both the echo time

and the $oppler shift of the reflected sounds to measure the distance to internal organs

and structures and the speed of movement of those structures. %ypical is the

echocardiogram, in #hich a moving image of the heart&s action is produced in video

form #ith false colors to indicate the speed and direction of blood flo# and heart valve

movements. 'ltrasound imaging near the surface of the body is capable of resolutions

less than a millimeter. %he resolution decreases #ith the depth of penetration since

lo#er fre!uencies must be used (the attenuation of the #aves in tissue goes up #ith

increasing fre!uency.) %he use of longer #avelengths implies lo#er resolution since the

ma*imum resolution of any imaging process is proportional to the #avelength of the

imaging #ave.

http://www.hielscher.com/degassing_01.htmhttp://www.hielscher.com/bottle_can_leak_testing_01.htmhttp://www.hielscher.com/wire_01.htmhttp://www.hielscher.com/degassing_01.htmhttp://www.hielscher.com/bottle_can_leak_testing_01.htmhttp://www.hielscher.com/wire_01.htm


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+rior to orld ar , sonar, the techni!ue of sending sound #aves through #ater and observing

the returning echoes to characterize submerged obects, inspired early ultrasound investigators to

e*plore #ays to apply the concept to medical diagnosis. n 1/2/ and 1/, Sokolov studied the

use of ultrasonic #aves in detecting metal obects. ulhauser, in 1/1, obtained a patent for using

ultrasonic #aves, using t#o transducers to detect fla#s in solids. irestone (1/30) and Simons

(1/3) developed pulsed ultrasonic testing using a pulse-echo techni!ue.

Shortly after the close of orld ar , researchers in 4apan began to e*plore medical diagnostic

capabilities of ultrasound. %he first ultrasonic instruments used an "-mode presentation #ith blips

on an oscilloscope screen. %hat #as follo#ed by a 5-mode presentation #ith a t#o dimensional,

gray scale imaging.

4apan&s #ork in ultrasound #as relatively unkno#n in the 'nited States and 6urope until the

1/0s. %hen researchers presented their findings on the use of ultrasound to detect gallstones,

breast masses, and tumors to the international medical community. 4apan #as also the firstcountry to apply $oppler ultrasound, an application of ultrasound that detects internal moving

obects such as blood coursing through the heart for cardiovascular investigation.

'ltrasound pioneers #orking in the 'nited States contributed many innovations and important

discoveries to the field during the follo#ing decades. 7esearchers learned to use ultrasound to

detect potential cancer and to visualize tumors in living subects and in e*cised tissue. 7eal-time

imaging, another significant diagnostic tool for physicians, presented ultrasound images directly onthe system&s 87% screen at the time of scanning. %he introduction of spectral $oppler and later

color $oppler depicted blood flo# in various colors to indicate

speed of flo# and direction.

%he 'nited States also produced the earliest hand held

9contact9 scanner for clinical use, the second generation of 5-

mode e!uipment, and the prototype for the first articulated-

arm hand held scanner, #ith 2-$ images.

Beginnings of Nondestructive Evaluation (NDE)

:ondestructive testing has been practiced for many decades, #ith initial rapid developments in

instrumentation spurred by the technological advances that occurred during orld ar and the

subse!uent defense effort. $uring the earlier days, the primary purpose #as the detection of

defects. "s a part of 9safe life9 design, it #as intended that a structure should not develop

macroscopic defects during its life, #ith the detection of such defects being a cause for removal of

the component from service. n response to this need, increasingly sophisticated techni!ues using

ultrasonics, eddy currents, *-rays, dye penetrants, magnetic particles, and other forms of


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interrogating energy emerged.

n the early 1/;0&s, t#o events occurred #hich caused a maor change. %he continued

improvement of the technology, in particular its ability to detect small fla#s, led to the

unsatisfactory situation that more and more parts had to be reected, even though the probability

of failure had not changed. Ho#ever, the discipline of fracture mechanics emerged, #hich enabled

one to predict #hether a crack of a given size #ould fail under a particular load if a material

property, fracture toughness, #ere kno#n.


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by the velocity of sound in the test material. %he result is e*pressed in the #ell-kno#n

relationship

d = vt/2 or v = 2d/t

#here d is the distance from the surface to the discontinuity in the test piece, v is the

velocity of sound #aves in the material, and t is the measured round-trip transit time.

%he diagram belo# allo#s you to move a transducer over the surface of a stainless

steel test block and see return echoes as they #ould appear on an oscilloscope. %he

transducer employed is a Hz broadband transducer 0.2 inches in diameter. %he

signals #ere generated #ith computer soft#are similar to that found in the %hompson-

?ray easurement odel and '%S developed at the 8enter for :ondestructive

6valuation at o#a State 'niversity.

+recision ultrasonic thickness gages usually operate at fre!uencies bet#een 00 kHz

and 100 Hz, by means of piezoelectric transducers that generate bursts of sound

#aves #hen e*cited by electrical pulses. " #ide variety of transducers #ith various

acoustic characteristics have been developed to meet the needs of industrial

applications. %ypically, lo#er fre!uencies are used to optimize penetration #hen

measuring thick, highly attenuating or highly scattering materials, #hile higher

fre!uencies #ill be recommended to optimize resolution in thinner, non-attenuating,

non-scattering materials.

n thickness gauging, ultrasonic techni!ues permit !uick and reliable measurement of

thickness #ithout re!uiring access to both sides of a part. "ccuracy&s as high as @1

micron or @0.0001 inch can be achieved in some applications. t is possible to measure

most engineering materials ultrasonically, including metals, plastic, ceramics,

composites, epo*ies, and glass as #ell as li!uid levels and the thickness of certain

biological specimens.


8/15

%he most commonly occurring defects in #elded oints are porosity, slag inclusions,

lack of side-#all fusion, lack of inter-run fusion, lack of root penetration, undercutting,

and longitudinal or transverse cracks.

ith the e*ception of single gas pores all the defects listed are usually #ell detectable

by ultrasonics. ost applications are on lo#-alloy construction !uality steels, ho#ever,

#elds in aluminum can also be tested. 'ltrasonic fla# detection has long been thepreferred method for nondestructive testing in #elding applications. %his safe, accurate,

and simple techni!ue has pushed ultrasonics to the forefront of inspection technology.

'ltrasonic #eld inspections are typically performed using a straight beam transducer in

conunction #ith an angle beam transducer and #edge. " straight beam transducer,

producing a longitudinal #ave at normal incidence into the test piece, is first used to

locate any laminations in or near the heat-affected zone. %his is important because an

angle beam transducer may not be able to provide a return signal from a laminar fla#.

%he second step in the inspection involves using an angle beam transducer to inspect

the actual #eld. "ngle beam transducers use the principles of refraction and mode

conversion to produce refracted shear or longitudinal #aves in the test material. A:oteB

any "S inspections are performed using refracted shear #aves. Ho#ever, material

having a large grain structure, such as stainless steel may re!uire refracted longitudinal

#aves for successful inspections.C %his inspection may include the root, side#all,

cro#n, and heat-affected zones of a #eld. %he process involves scanning the surface of


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the material around the #eldment #ith the transducer. %his refracted sound #ave #ill

bounce off a reflector (discontinuity) in the path of the sound beam. ith proper angle

beam techni!ues, echoes returned from the #eld zone may allo# the operator to

determine the location and type of discontinuity.

%o determine the proper scanning area for the #eld, the inspector must first calculate

the location of the sound beam in the test material. 'sing the refracted angle, beam

inde* point and material thickness, the D-path and skip distance of the sound beam is

found.


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e*ist> ho#ever, there is the 8enter for the Holographic "rts in :e# ForkA3;C and the H


11/15

n static holography, recording, developing and reconstructing occur se!uentially, and a permanent hologram is

produced.

%here also e*ist holographic materials that do not need the developing process and can record a hologram in a

very short time. %his allo#s one to use holography to perform some simple operations in an all-optical #ay.

6*amples of applications of such real-time holograms include phase-conugate mirrors (9time-reversal9 of light),

optical cache memories, image processing (pattern recognition of time-varying images), andoptical computing.

%he amount of processed information can be very high (terabitsLs), since the operation is performed in parallel

on a #hole image. %his compensates for the fact that the recording time, #hich is in the order of a microsecond,

is still very long compared to the processing time of an electronic computer. %he optical processing performed by

a dynamic hologram is also much less fle*ible than electronic processing.


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any of these holographers #ould go on to produce art holograms. n 1/, red 'nterseher published

the Holography Handbook , a remarkably easy-to-read description of making holograms at home. %his brought in

a ne# #ave of holographers and gave simple methods to use the then-available "?" silver halide recording

materials.

n 2000, rank $ereitas published the Shoebox Holography Book and introduced the use of ine*pensive laser

pointers to countless hobbyists. %his #as a very important development for amateurs, as the cost for a mlaser dropped from M1200 to M as semiconductor laser diodes reached mass market. :o#, there are hundreds

to thousands of amateur holographers #orld#ide.

5y late 2000, holography kits #ith the ine*pensive laser pointer diodes entered the mainstream consumer

market. %hese kits enabled students, teachers, and hobbyists to make many kinds of holograms #ithout

specialized e!uipment, and became popular gift items by 200. A3C %he introduction of holography kits #ith self-

developing film plates in 200 made it even possible for hobbyists to make holograms #ithout using chemical

developers.AC

n 200G, a large number of surplus Holography =uality ?reen Iasers (8oherent 81) became available and put

$ichromated ?elatin ($8?) #ithin the reach of the amateur holographer. %he holography community #as

surprised at the amazing sensitivity of $8? to green light. t had been assumed that the sensitivity #ould be

non-e*istent. 4eff 5lyth responded #ith the ?0; formulation of $8? to increase the speed and sensitivity to

these ne# lasers.AGC

any film suppliers have come and gone from the silver-halide market. hile more film manufactures have filled

in the voids, many amateurs are no# making their o#n film. %he favorite formulations are $ichromated ?elatin,

ethylene 5lue Sensitised $ichromated ?elatin and $iffusion ethod Silver Halide preparations. 4eff 5lyth has

published very accurate methods for making film in a small lab or garage. A;C

" small group of amateurs are even constructing their o#n pulsed lasers to make holograms of moving obects.

AC

Holographic interferometryAeditC

Main article: holographic interferometry

Holographic interferometry (H) is a techni!ue that enables static and dynamic displacements of obects #ith

optically rough surfaces to be measured to optical interferometric precision (i.e. to fractions of a #avelength of

light).A/CAG0C t can also be used to detect optical-path-length variations in transparent media, #hich enables, for

e*ample, fluid flo# to be visualized and analyzed. t can also be used to generate contours representing the form

of the surface.

t has been #idely used to measure stress, strain, and vibration in engineering structures.

nterferometric microscopyAeditC

Main article: Interferometric microscopy

http://en.wikipedia.org/wiki/Silver_halidehttp://en.wikipedia.org/wiki/Silver_halidehttp://en.wikipedia.org/wiki/Frank_DeFreitashttp://en.wikipedia.org/wiki/Frank_DeFreitashttp://en.wikipedia.org/wiki/Laser_pointerhttp://en.wikipedia.org/wiki/Laser_pointerhttp://en.wikipedia.org/wiki/Laser_pointerhttp://en.wikipedia.org/wiki/Hobbyhttp://en.wikipedia.org/wiki/Holography#cite_note-IEEE-54http://en.wikipedia.org/wiki/Holography#cite_note-physicsteacher-55http://en.wikipedia.org/wiki/Lighthttp://en.wikipedia.org/wiki/Holography#cite_note-56http://en.wikipedia.org/wiki/Holography#cite_note-57http://en.wikipedia.org/wiki/Holography#cite_note-58http://en.wikipedia.org/w/index.php?title=Holography&action=edit&section=29http://en.wikipedia.org/wiki/Holographic_interferometryhttp://en.wikipedia.org/wiki/Holographic_interferometryhttp://en.wikipedia.org/wiki/Holography#cite_note-59http://en.wikipedia.org/wiki/Holography#cite_note-60http://en.wikipedia.org/w/index.php?title=Holography&action=edit&section=30http://en.wikipedia.org/wiki/Interferometric_microscopyhttp://en.wikipedia.org/wiki/Interferometric_microscopyhttp://en.wikipedia.org/wiki/Silver_halidehttp://en.wikipedia.org/wiki/Frank_DeFreitashttp://en.wikipedia.org/wiki/Laser_pointerhttp://en.wikipedia.org/wiki/Laser_pointerhttp://en.wikipedia.org/wiki/Hobbyhttp://en.wikipedia.org/wiki/Holography#cite_note-IEEE-54http://en.wikipedia.org/wiki/Holography#cite_note-physicsteacher-55http://en.wikipedia.org/wiki/Lighthttp://en.wikipedia.org/wiki/Holography#cite_note-56http://en.wikipedia.org/wiki/Holography#cite_note-57http://en.wikipedia.org/wiki/Holography#cite_note-58http://en.wikipedia.org/w/index.php?title=Holography&action=edit&section=29http://en.wikipedia.org/wiki/Holographic_interferometryhttp://en.wikipedia.org/wiki/Holography#cite_note-59http://en.wikipedia.org/wiki/Holography#cite_note-60http://en.wikipedia.org/w/index.php?title=Holography&action=edit&section=30http://en.wikipedia.org/wiki/Interferometric_microscopy


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%he hologram keeps the information on the amplitude and phase of the field. Several holograms may keep

information about the same distribution of light, emitted to various directions. %he numerical analysis of such

holograms allo#s one to emulate large numerical aperture, #hich, in turn, enables enhancement of the

resolution of optical microscopy. %he corresponding techni!ue is called interferometric microscopy. 7ecent

achievements of interferometric microscopy allo# one to approach the !uarter-#avelength limit of resolution. AG1C

Sensors or biosensorsAeditC

Main article: Holographic sensor

%he hologram is made #ith a modified material that interacts #ith certain molecules generating a change in the

fringe periodicity or refractive inde*, therefore, the color of the holographic reflection. AG2CAGC

SecurityAeditC

Main article: Security hologram

Identigram as a security element in a ?erman identity card

Security holograms are very difficult to forge, because they are replicated from a master hologram that re!uires

e*pensive, specialized and technologically advanced e!uipment. %hey are used #idely in many currencies, such

as the 5razilian 20, 0, and 100-reais notes> 5ritish , 10, and 20-pound notes> South Norean 000, 10,000, and

0,000-#on notes> 4apanese 000 and 10,000 yen notes> and all the currently-circulating banknotes of

the 8anadian dollar , $anish krone, and 6uro. %hey can also be found in credit and bank cards as #ell

as passports, $ cards, books, $D$s, and sports e!uipment.

8overtly storing information #ithin a full colour image hologram #as achieved in 8anada, in 200, at the 'H7

lab. %he method used a fourth #avelength, aside from the 7?5 components of the obect and reference beams,to record additional data, #hich could be retrieved only #ith the correct key combination of #avelength and

angle. %his techni!ue remained in the prototype stage and #as never developed for commercial applications.


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Non-optical holography AeditC

n principle, it is possible to make a hologram for any #ave.

6lectron holography is the application of holography techni!ues to electron #aves rather than light #aves.

6lectron holography #as invented by $ennis ?abor to improve the resolution and avoid the aberrations of

the transmission electron microscope. %oday it is commonly used to study electric and magnetic fields in thinfilms, as magnetic and electric fields can shift the phase of the interfering #ave passing through the sample.

AGC %he principle of electron holography can also be applied to interference lithography.AGGC

"coustic holography is a method used to estimate the sound field near a source by measuring acoustic

parameters a#ay from the source via an array of pressure andLor particle velocity transducers. easuring

techni!ues included #ithin acoustic holography are becoming increasingly popular in various fields, most notably

those of transportation, vehicle and aircraft design, and :DH. %he general idea of acoustic holography has led to

different versions such as near-field acoustic holography (:"H) and statistically optimal near-field acoustic

holography (S


15/15

8rypton uture edia, a music soft#are company that produced Hatsune iku,A;1C one of many Docaloid singing

synthesizer applications, has produced concerts that have iku, along #ith other 8rypton Docaloids, performing

on stage as 9holographic9 characters. %hese concerts use rear proection onto a semi-transparent $I"$

screenA;2CA;C to achieve its 9holographic9 effect.A;3CA;CA;GC

n 2011, in 5eiing, apparel company 5urberry produced the 95urberry +rorsum "utumnLinter 2011 Hologram

7un#ay Sho#9, #hich included life size 2-$ proections of models. %he company&s o#n videoA;;C

sho#s severalcentered and off-center shots of the main 2-dimensional proection screen, the latter revealing the flatness of the

virtual models. %he claim that holography #as used #as reported as fact in the trade media. A;C

icrosoft Hololens can potentially be mistaken for a true hologram.

Holography in fictionAeditC

Main article: Holography in fiction

Holography has been #idely referred to in novels, %D and movies.
http://en.wikipedia.org/wiki/Crypton_Future_Mediahttp://en.wikipedia.org/wiki/Hatsune_Mikuhttp://en.wikipedia.org/wiki/Holography#cite_note-71http://en.wikipedia.org/wiki/Vocaloidhttp://en.wikipedia.org/wiki/Vocaloidhttp://en.wikipedia.org/wiki/Holography#cite_note-72http://en.wikipedia.org/wiki/Holography#cite_note-72http://en.wikipedia.org/wiki/Holography#cite_note-73http://en.wikipedia.org/wiki/Holography#cite_note-74http://en.wikipedia.org/wiki/Holography#cite_note-75http://en.wikipedia.org/wiki/Holography#cite_note-75http://en.wikipedia.org/wiki/Holography#cite_note-76http://en.wikipedia.org/wiki/Burberryhttp://en.wikipedia.org/wiki/Burberryhttp://en.wikipedia.org/wiki/Holography#cite_note-77http://en.wikipedia.org/wiki/Holography#cite_note-78http://en.wikipedia.org/wiki/Microsoft_Hololenshttp://en.wikipedia.org/wiki/Microsoft_Hololenshttp://en.wikipedia.org/w/index.php?title=Holography&action=edit&section=36http://en.wikipedia.org/wiki/Holography_in_fictionhttp://en.wikipedia.org/wiki/Holography_in_fictionhttp://en.wikipedia.org/wiki/Crypton_Future_Mediahttp://en.wikipedia.org/wiki/Hatsune_Mikuhttp://en.wikipedia.org/wiki/Holography#cite_note-71http://en.wikipedia.org/wiki/Vocaloidhttp://en.wikipedia.org/wiki/Holography#cite_note-72http://en.wikipedia.org/wiki/Holography#cite_note-73http://en.wikipedia.org/wiki/Holography#cite_note-74http://en.wikipedia.org/wiki/Holography#cite_note-75http://en.wikipedia.org/wiki/Holography#cite_note-76http://en.wikipedia.org/wiki/Burberryhttp://en.wikipedia.org/wiki/Holography#cite_note-77http://en.wikipedia.org/wiki/Holography#cite_note-78http://en.wikipedia.org/wiki/Microsoft_Hololenshttp://en.wikipedia.org/w/index.php?title=Holography&action=edit&section=36http://en.wikipedia.org/wiki/Holography_in_fiction

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