Optics Tutorial LAK

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    Basic OpticsLaura KranendonkERC, UW Madison

    2004

    Table of Contents

    Basic Optics

    1. Introduction 1

    2. Proerties o! Li"#t.. 1

    a. Co$or 1%. &ectra$ Po'er 2

    c. Po$ari(ation. 4

    ). *tica$ +undaenta$s. 4a. +erat-s Princi$e

    %. &ne$$-s La'. /c. +resne$ Euations.

    d. Etendue e. Co#erence 11

    !. &catterin". 1)

    Optical Laboratory Toolbox

    1. Introduction. 1

    2. Creatin" Li"#t.. 1a. Lasers.. 1

    %. LE3s.. 1

    ). 3irectin" Li"#t.. 1a. LensesMirrors. 1

    %. +i%ers.. 22

    4. Contro$$in" Wa5e$en"t#. 24

    a. 3i!!raction 6ratin". 24%. Eta$ons.. 2/

    c. 7aronic 6eneration 2

    . Measurin" Li"#t.. 28a. 3etectors.. 28

    %. Caeras39es 28

    Appendix1. &I Pre!i:es.. 2

    2. Laser C$assi!ications.. 2

    ). Cornin" &M+;28 *tica$ +i%er Product 3ata s#eet

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    Basic Optics

    Introduction

    In 1/0, t#e !irst Ru%9 $aser 'as %ui$t >1?, oenin" t#e door !or an9 ne' otica$

    in5entions and researc# toics. Mec#anica$ en"ineers in articu$ar are current$9 'orkin"on otica$ et#ods !or easurin" !$uid and "as roerties, easurin" ec#anica$

    stresses, and anu!acturin" tec#niues. In order to understand t#ese ne' de5e$oents,

    a %asic understandin" o! $i"#t and $i"#t roerties is reuired. @#ese notes are eanton$9 as a re5ie' o! $i"#t toics in order to understand rinci$es coon$9 used in t#e

    ec#anica$ en"ineer-s otica$ $a%orator9. @#e #9sics %e#ind t#e ateria$s %ein"

    resented are "enera$$9 co5ered in introductor9 #9sics courses.

    Properties of Light

    Aisi%$e $i"#t is a sa$$ art o! t#e e$ectroa"netic sectru. E$ectroa"netic 'a5es

    #a5e e$ectric and a"netic !ie$ds erendicu$ar to t#e direction o! otion. @#e9 are a%$e

    to tra5e$ t#rou"# a 5acuu or a ediu. @#ere are se5era$ roerties coon$9 used todescri%e $i"#t suc# as co$or B'a5e$en"t#, 'a5enu%er, !reuenc9, ener"9, and o'er

    Bintensit9.

    Figure 1.1 E$ectroa"netic sectru, #ttD#9er#9sics.#9;astr."su.edu#%asees1.#t$

    Wa5e$en"t# BD easured in nanoeters Bn, icroeters B, or an"stros B , 1 0.1 n, t#e distance !ro one eak to t#e ne:t.

    +reuenc9 B!D easured in 7ert( B7(, 17( 1s;1. +reuenc9 is t#e in5erse o! t#e tie

    it 'ou$d take a 'a5e to tra5e$ 1 'a5e$en"t#. @o ca$cu$ate !reuenc9 !ro 'a5e$en"t#D

    fc= B1.1&eed o! $i"#t in a 5acuu Bc ) : 108s

    Wa5enu%er BD easured in in5erse centieters Bc;1. @#e 'a5enu%er is #o'

    an9 'a5es !it in t#e distance o! 1 c.

    2

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    Ener"9 BED easured in Fo$e, F#oton, or e$ectron 5o$t BeA, 1eA1./ : 10;1F er

    #oton or er o$e o! #otons. Ener"9 o! t#e 'a5e can %e ca$cu$ated direct$9 !ro t#e

    'a5e$en"t# or !reuenc9 usin" t#e !o$$o'in" euationD

    chhfE == B1.2

    P$anck-s constant, h/./2/ : 10;)4

    Fs.!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    !"xa#ple 1.1

    a. Consider a 10 n 'a5e. W#at are t#e !reuenc9, 'a5enu%er and

    ener"9 Bin a 5acuuG

    Frequency:

    ( ) Hz

    s

    Hz

    m

    nm

    nms

    mcf 14

    8

    10H4.11

    1H

    10

    1H

    10

    1H

    10H)=

    ==

    1$% T&'

    Wavenumber:

    =

    cm

    m

    m

    nm

    nm 100

    1H

    10

    1H

    10

    1

    (%)1.(1c#*1

    Energy:

    ( )

    ==

    sxJsxhfE

    1104.1H10/2/./ 14)4 1.+,)x1-*1$/photon

    %. Consider t#e dia"ra %e$o'. W#at is , , and !G

    W#en ca$cu$atin" di!!erences, it is iortant con5ert into coon unitsbeforetakin" t#e di!!erence.

    00n;/00n 1--n#

    cm

    m

    m

    nm

    nmnm 100

    1H

    10

    1H

    00

    1

    /00

    1 +0,-.$)c#

    *1

    )

    >n?

    P

    >W?

    /00 00

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    nm

    mW.. in

    0001.0

    1=

    =

    1- 3/n#

    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    !

    Po$ari(ationD W#en t#e e$ectroa"netic 'a5es coosin" a $i"#t %ea 5i%rate in t#esae direction, t#e $i"#t is said to %e o$ari(ed. Po$ari(ed $i"#t is "enera$$9 c$assi!ied into

    2 "rous deendin" on #o' t#e e$ectric 'a5es are a$i"ned 'it# t#e $ane o! incidence.

    @#e $ane o! incidence is t#e $ane coosin" t#e incident, re!$ected, and transitted

    ra9s. @rans5erse a"netic B@M, ara$$e$ BJJ, P, and * are a$$ 'a9s to re!er to 'a5es t#atare o$ari(ed suc# t#at t#e e$ectric !ie$d is in t#e $ane o! incidence. @rans5erse e$ectric

    B@E, erendicu$ar B , &, and E are a$$ 'a9s to re!er to o$ari(ation erendicu$ar tot#e $ane o! incidence. @#e o$ari(ation o! $i"#t can a!!ect an9 asects o! otics.Materia$s can #a5e di!!erent roerties !or di!!erent o$ari(ations, suc# as inde:es o!

    re!raction B%ire!rin"ents or re!$ecti5it9. In addition to t#ese o$ari(ed cases, $i"#t can %e

    rando$9 o$ari(ed Ba$so ca$$ed natura$ $i"#t, or circu$ar$9 or e$$itica$$9 o$ari(ed.

    Figure 1.0Para$$e$ o$ari(ation dia"ra.

    Figure 1.%Perendicu$ar o$ari(ation dia"ra.

    Optical Funda#entals

    In t#is section, !undaenta$ otica$ rinci$es 'i$$ %e re5ie'ed in order to understand$i"#t %e#a5ior. *nce t#ese %asic rinci$es are understood, co$e: otica$ a$ications

    W#en t#e e$ectric !ie$d

    BE is ara$$e$ to t#eaer Bas dra'n, it is

    ca$$edD @M, P, *, or JJ.

    @#e ara$$e$ $ines are 1

    reresentation o! t#iso$ari(ation.

    Incident ra9 Re!$ected ra9

    @ransitted ra9

    W#en t#e e$ectric !ie$dBE is erendicu$ar to

    t#e aer $ane, it is

    ca$$edD @E, &, E, or .

    @#e dots are 1

    reresentation o! t#is

    o$ari(ation.

    Incident ra9 Re!$ected ra9

    @ransitted ra9

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    and too$s can %e studied. @#ere!ore, it is 5er9 iortant to #a5e a "ood understandin" o!

    t#ese !undaenta$ rinci$es.

    +erat-s Princi$e

    +erat-s rinci$e states t#at $i"#t 'i$$ take at# 'it# t#e s#ortest tra5e$ tie to "o !ro

    one oint to anot#er, as s#o'n in !i"ure 4.

    Figure 1.) I$$ustration o! +erat-s rinci$e, $i"#t 'i$$ tra5e$ in a strai"#t $ine !ro one oint to anot#er

    since a strai"#t $ine 'i$$ %e t#e uickest at#.

    +erat-s rinci$e can %e used to s#o' t#e %e#a5ior o! re!$ection. 3eendin" on t#e

    incident an"$e o! t#e $i"#t onto a sur!ace Bsa9 a irror, $i"#t 'i$$ on$9 re!$ect at t#at sae

    incident an"$e. @#ere!oreD

    ri = B1.)

    Figure 1.(+erat-s rinci$e on a irror. @#e %ea !ro t#e das#ed at# is iossi%$e %ecause it is a

    $on"er tra5e$ tie t#an t#e so$id $ine at#.

    +erat-s rinci$e can a$so %e used to s#o' #o' a $ens !ocuses $i"#t. In order tounderstand t#is #enoenon, it is iortant to kno' t#at $i"#t tra5e$s at di!!erent seeds

    deendin" on t#e inde: o! re!raction Bn o! t#e ateria$. 6$ass t9ica$$9 #as an inde: o!re!raction o! a%out 1., '#ereas air #as an inde: o! re!raction o! essentia$$9 1 Bc seedo! $i"#t in a 5acuu. @#e seed t#at $i"#t tra5e$s t#rou"# a ediu isD

    n

    cvlight= B1.4

    In !i"ure /, it can t#en %e deduced t#at $i"#t 'i$$ tra5e$ !ro oint = to oint in t#esae aount o! tie Band t#ere!ore t#e s#ortest aount o! tie !or a$$ o! t#e $ines.

    BHintD t#e t#ickest art o! t#e $ens #as t#e o5era$$ s#ortest at# $en"t#, %ut since t#e $i"#t

    /

    2

    1

    1

    2

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    'i$$ tra5e$ s$o'er in t#e "$ass, t#e o5era$$ tie to tra5e$ !ro = to 'i$$ %e t#e sae !or

    t#e center$ine.

    Figure 1. Li"#t at#'a9s t#rou"# a $ens, oint = and are at t'ice t#e !ocus $en"t# o! t#e $ens.

    &ne$$-s La'

    &ne$$-s $a' redicts t#e direction o! $i"#t as it tra5e$s t#rou"# di!!erent edius. &ne$$-s$a' can %e stated %9 t#e !o$$o'in" euation '#ere nis t#e inde: o! re!raction, and i, t,andrstand !or incident, transitted, and re!$ected.

    ttii nn sinsin = B1.

    Figure 1.,3ia"ra o! &ne$$-s $a', s#o'in" $i"#t tra5e$in" !ro air to "$ass.

    @ota$ interna$ re!$ection can occur '#en $i"#t in a #i"# inde: ediu reac#es a $o'

    inde: ediu Bni nt. In t#ese conditions, '#en t0o, t#e corresondin" incident

    an"$e is ca$$ed t#e critica$ an"$e. =n9 incident ra9 at t#e critica$ an"$e or #i"#er 'i$$

    cause tota$ interna$ re!$ection, eanin" a$$ o! t#e $i"#t is re!$ected and none is transitted.@#is 'i$$ %ecoe iortant '#en dea$in" 'it# !i%er otic ca%$es.

    n"$ass

    1.

    nair

    1

    r

    t

    i

    =

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    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    "xa#ple 1.0

    a. Consider a %ea tra5e$in" !ro air Bn1 to "$ass Bn1. at a )0oincident an"$e. &ketc# t#e s9ste, ca$cu$atin" t#e re!$ection and

    transission an"$es.

    ri = 0-oB+erat-s Princi$e

    ttii nn sinsin = B&ne$$-s La'o

    iti nn )0L.1L1 ===

    ( )

    = )0sinH

    .1

    1sin 1t 1$.%

    o

    %. W#at is t#e critica$ an"$e Bonset o! tota$ interna$ re!$ection !or a"$assair inter!aceG inc;&e$enideair Bn2.G

    @o !ind t#e onset o! tota$ interna$ re!$ection B@IR, set t#e transissionan"$e eua$ to 0o. @#ere!oreD

    /lass:

    ( )

    =

    = 1H

    1

    .1sin0sinsin 11

    i

    ti

    n

    n %1.,o

    0inc"1elenide:

    ( )

    =

    = 1H

    1

    .2sin0sinsin 11

    i

    t

    i

    n

    n +0.),o

    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    +resne$-s Euations

    @#e aount o! $i"#t t#at is transitted or re!$ected can %e deterined %9 t#e +resne$

    euations. @#e ratio o! re!$ected to incident o'er Bor t#e !raction o! o'er re!$ecteddeends on t#e o$ari(ation o! t#e $i"#t, and can %e 'ritten asD

    8

    n"$ass

    1.

    nair

    1

    )0o

    1.o

    )0o

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    2

    JJcoscos

    coscos

    +

    =itti

    tiit

    nn

    nn2

    BPara$$e$ o$ari(ed $i"#t B1./

    2

    coscos

    coscos

    +

    =ttii

    ttii

    nn

    nn2

    BPerendicu$ar o$ari(ed $i"#t B1.

    '#ic# can %e si$i!ied to

    2

    +

    =ti

    it

    nn

    nn2 '#en i0. 2is a$so ca$$ed t#e re!$ected

    o'er coe!!icient. I! no $i"#t is a%sor%ed in t#e ateria$, transitted o'er can t#en %e

    ca$cu$ated %9 initia$ o'er u$ti$ied %9D

    C1B 23 = B1.8!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    !"xa#ple 1.%

    a. I! a 1W $aser %ea is directed t#rou"# a "$ass icroscoe s$ide,'#at is t#e transitted o'erG (4ssume there is no 5o6er absor5tion in

    the glass)

    Usin" t#e +resne$ euations, it is ossi%$e to ca$cu$ate t#e re!$ected o'er

    coe!!icient !or %ot# t#e air"$ass inter!ace, and t#e "$ass air inter!ace. It

    turns out t#at t#ese are t#e saeD

    04.0.2

    .0 22

    =

    =

    +

    =ti

    it

    nn

    nn2

    &ince t#ere is no a%sor%ance, t#e transitted o'er coe!!icient is t#en Nust1;2. @#ere!ore, /O B1;0.04 o! t#e o'er is transitted, or 0./W.

    %. W#at 'ou$d %e t#e transitted o'er i! t#ere 'ere 0 icroscoe

    s$ides %et'een t#e $aser and detectorG (4ssume an air ga5 bet6een eachslide)

    Rea$i(in" t#at at eac# inter!ace, /O o! t#e o'er is transitted, and t#ereare a tota$ o! 100 inter!aces, it can %e deduced t#atD

    01/.0C/.0B 100 ==3@#ere!ore, 1./O o! t#e ori"ina$ o'er or 0.01/W is transitted.

    1W $aser

    air"$ass inter!ace

    "$assair inter!ace

    Li"#t detector,

    a%$e to easureo'er o! $i"#t

    %ea.

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    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    !

    Figure 1.$Re!$ection 5ersus incident an"$e !or an air"$ass s9ste.

    Euations B1.4 and B1. can %e $otted 5ersus incident an"$e, as s#o'n in !i"ure 1.. =t

    /.4o, t#ere is no re!$ection !or one o! t#e o$ari(ations. @#is is a secia$ incident an"$ekno'n as re'ster-s an"$e. 9 aniu$atin" t#e incident an"$e, it is ossi%$e to o$ari(e

    uno$ari(ed $i"#t.

    "xa#ple 1.)

    I! t#ere 'ere t#e sae 0 s$ides as in e:a$e 1.), %ut no' t#e incident

    an"$e 'as at re'ster-s an"$e, '#at 'ou$d t#e transitted o'er %eG

    (4ssume the light is un5olarized* and equal amounts of 5er5endicular and5arallel"5olarized light)

    4ns6er:

    =t re'ster-s an"$e, none o! t#e ara$$e$;o$ari(ed $i"#t 'i$$ %e re!$ectedB100O transission, or 0O net transission. +ro euation Bor !ro

    t#e "ra# in !i"ure 8, t#e re!$ection !or 1 air"$ass and "$assair 0.14.

    @#ere!ore, t#e erendicu$ar o$ari(ed $i"#t transits 8.1O B1;0.14 ateac# inter!ace, so o5er a$$ 100 inter!aces, 0.81100.84:10;8is transitted

    Bessentially !.

    *5era$$, t#e tota$ transission is t#en )-4.

    Etendue

    Etendue, a$so kno'n as t#e araeter roduct, can %e t#ou"#t o! as t#e ua$it9 o! $i"#t,and is uanti!ied %9 si(e u$ti$ied %9 di5er"ence. @#e sa$$er t#e etendue, t#e %etter

    co$$iated t#e $i"#t can %e. Etendue is t#e otica$ eui5a$ent o! entro9 at %est it 'i$$

    10

    Reflection versus incident angle (air-glass interface)

    0

    0.2

    0.4

    0.6

    0.8

    1

    0 20 40 60 80 100

    Incident Angle

    Reflectance

    RJJ

    R

    re'ster-san"$e/.4o

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    reain constant, #o'e5er it 'i$$ ne5er iro5e. +i"ure 1.10 s#o's #o' etendue is

    ca$cu$ated and "ra#ica$$9 reresented.

    Figure 1.1- 6ra#ica$ reresentation o! etendue.

    @#e sa$$est etendue ossi%$e is ca$$ed t#e di!!raction $iit. @#e di!!raction $iit is

    'a5e$en"t# deendent, and can %e ca$cu$ated !ro t#e !o$$o'in" euation, '#ere dis t#e

    sot si(eQ, t#e diaeter o! t#e $i"#t sourceD

    ( )

    halfdH B1.8

    @#e di!!raction $iit t#ere!ore $eads to t#e iniu sot si(e t#at a %ea cou$d roduce

    Brat#er t#an an in!inite$9 sa$$ oint. Lasers are a%$e to roduce $i"#t t#at is neardi!!raction $iited. = "enuine increase in etendue is ca$$ed %ea steerin".

    "xa#ple 1.(

    a. Li"#t at /10 n, $ea5es a $aser at t#e di!!raction $iit. @#e$aser #as a 1 diaeter eittin" area. W#at is t#e di5er"ence

    an"$e o! t#e $aserG

    =halfdH

    =

    m

    m

    nm

    m

    m

    nmhalf

    1

    10H

    10

    1H

    1

    1H

    /10 /

    11.1+)o

    %. I! t#e $aser %ea 'ere co$$ected in a 1 c diaeter $ens at t#e !oca$$en"t#, #o' $ar"e 'ou$d t#e roNected sot %e 10 k !ro t#e $ensG

    First* calculated the divergence angle leaving the lens:

    ( ) ( )2211 sinsin rr =

    mmr

    .02

    11 =

    =

    11

    !

    a1

    1

    2

    2

    Etendue %est caseD

    a1sinB

    1a

    2sinB

    2

    1tan;1Ba

    2!

    2tan;1Ba

    1!

    Li"#t source

    a2

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    cmr

    o

    .0

    2.22

    2

    1

    =

    =

    ( )

    =

    =

    m

    cm

    m

    m

    cm

    m

    r

    r o

    1

    100H

    10

    1H

    .0

    2.22sinH.0sin

    CsinBsin

    /

    1

    2

    1112

    0.002o

    Next* using trigonometry* figure outthe size of the s5ot:

    ( ) ( )o7r 002.0tanH10000tanH 2) == 0.) 2

    )H r4 = -.%) #+

    Co#erence

    W#en 2 or ore $i"#t %eas are sueriosed on eac# ot#er, t#e9 #a5e t#e otentia$ to%e eit#er co#erent or inco#erent. W#en co#erent $i"#t #as t#e sae eaks and 5a$$e9s, it

    constructi5e$9 inter!eres, '#ereas i! a eak $ines u 'it# a 5a$$e9, t#ere is destructi5e

    inter!erence, '#ic# 'eakens t#e si"na$.

    W#en 'a5es o! di!!erent 'a5e$en"t#s are tra5e$in" a$on" t#e sae at#, it is use!u$ tokno' at '#at $en"t# t#e 'a5es %ecoe inco#erent. @#is co#erence $en"t#- can %e

    ca$cu$ated 'it# t#e !o$$o'in" euationD

    =

    2

    c7 B1.

    12

    Destructive Interference

    -1.5

    0

    1.5

    0

    Constructive Interference

    -2

    0

    2

    0 250

    Incoherent Light

    -1.2

    0

    1.2

    0

    Figure 1.11E:a$es o! destructi5e and constructi5e

    inter!erence, and inco#erent $i"#t.

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    "xa#ple 1.

    @'o 10 W $asers eittin" 5er9 near$9 t#e sae co$or are arran"ed ass#o'n %e$o'. @#e to $aser is a !ree;runnin" $aser, and t#e %otto is a

    sta%i$i(ed $aser t#e sta%i$i(ed $aser #as a si"ni!icant$9 sa$$er $ine'idt#.

    @#e !u$$ 'idt# #a$! a:- B+W7M o! t#e to $aser is 0.1 c;1

    , and t#e+W7M o! t#e $o'er $aser is )00 k7(. +W7M is t#e %and'idt# at #a$! t#ea:iu, since ost $asers and ot#er otica$ sources roduce 'a5es on a

    6aussian cur5e +W7M is a "ood aro:iation o! %and'idt#.

    +ree runnin" $aserD fr 00.01 n, +W7M 0.1c;1

    &ta%i$i(ed $aserD s 00 n, +W7M )00 k7(

    a. W#at is t#e co#erence $en"t# o! t#e 2 $asersG

    Free running laser:

    +

    =

    frfrfrfr

    fr

    nm

    m

    m

    cmcm

    H.0

    1

    H.0

    1

    10

    1H

    1

    100H

    1

    fr 0.004 n

    nm

    m

    nm

    nm7 frc

    222

    ,10

    1H

    004.0

    01.00=

    =

    -.1 #

    1tabilized laser:

    +

    =

    ssss

    cHz

    Hz8Hz

    H.0

    1

    H.0

    1H

    1

    1000H

    s4.:10;n

    nm

    m

    nmx

    nm7

    s

    s

    sc

    222

    ,10

    1H

    10.4

    00

    =

    =

    15--- #

    %. @#e detector is not readin" a si"na$. W#9 cou$d t#is %eG

    4ns6er:

    1)

    +ree runnin"

    sta%a$i(ed

    3etectorLasersD

    %ea s$itter

    irror

    )0 c

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    &ince t#e co#erence $en"t# in t#e !ree;runnin" $aser is s#orter t#an t#e at#

    it is tra5e$in", t#e $i"#t %ecoes inco#erent, and t#ere!ore cannot a$i"n

    'it# t#e sta%i$i(ed $aser.

    &catterin"W#en $i"#t #its o$ecu$es, it can %ecoe scattered in se5era$ 'a9s. W#en $i"#t is

    scattered %9 5er9 sa$$ o$ecu$es Bd SS e$astic BRa9$ei"# scatterin", ine$astic 'it#

    increased ener"9 B=nti;&tokes Raan scatterin", or ine$astic 'it# decreased ener"9

    B&tokes Raan scatterin" scatterin" can occur. W#en $i"#t is scattered %9 $ar"er

    o$ecu$es Bd, Mie scatterin" occurs.

    @#e incident o'er, densit9 o! o$ecu$es, 5o$ue o! interest, and co$$ection an"$e o! t#e

    otics can deterine t#e scattered o'er !or eac# t9e o! scatterin". @#e euation !or

    scattered o'er is as !o$$o'sD

    =

    n7.

    .

    9

    s

    B1.10

    9

    s

    .

    . ratio o! scattered o'er to incident o'er

    di!!erentia$ scatterin" cross;section

    &rHo$ecu$es

    c2

    so$id an"$e o! co$$ection >&r?, 1 &teradian 4Hradians

    n o$ecu$ar densit9

    (at standard tem5erature and 5ressure* air has a molecular density of:

    #&+!

    '

    molecules;cm

    $

    )2ayleigh:

    42

    22 C1B4

    o2ayleigh N

    n=

    B1.11

    13.nmatN2ayleigh 1rmolec

    cm

    ,00

    2

    28

    2

    10H4.8

    !or en. B1.11, n re!racti5e inde: o! o$ecu$e

    No nu%er densit9 at &@P

    @#is in5erse re$ations#i 'it# 'a5e$en"t# can %e used to e:$ain '#9 durin" t#e da9, t#e

    sk9 is %$ue and not red. =s t#e sun sets, t#e sun-s ra9s tra5e$ t#rou"# ore o! t#eatos#ere, a$$o'in" ore scatterin", causin" t#e sunset to %e a redder co$or.

    2aman:

    2ayleigh2aman

    )10

    -ie:

    14

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    2

    2d-ie

    =

    d diaeter o! scatterin" o$ecu$e

    Wa5e$en"t# c#an"es due to Raan scatterin" can %e ca$cu$ated %9 t#e !o$$o'in"euationsD

    =nti;&tokes RaanDhEEE +=+ TL B1.12

    &tokes RaanDh

    EEE

    = TL B1.1)

    "xa#ple 1.,

    = 1 W $aser at 00n is directed into air at roo teerature and

    ressure. I! a detector cou$d ick u 10O o! t#e area o! a s#ere, and 1 c$on", #o' uc# o'er 'ou$d %e detected due to Ra9$ei"# scatterin"G

    4ns6er:

    =

    2ayleigh9

    s n7

    .

    .

    n2.H101o$ecu$esc)

    0.1H4 1.2/

    71 c

    =

    1rmolecule

    cmx

    2ayleigh H104.8

    228

    .s 2.8/:10;8W

    Conclusions

    In t#is section, 'e #a5e de5e$oed t#e too$s necessar9 to understand #enoena dea$in"'it# otics. Wit# t#ese !undaenta$ rinci$es, 'e can no' o5e a#ead to $earnin"a%out t#e instruents used in otica$ $a%oratories, and ot#er otica$ a$ications.

    1

    L

    Pin

    3etector

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    Optical Laboratory Toolbox

    In t#e otica$ $a%orator9, it is iortant to %e a%$e to contro$ t#e direction, 'a5e$en"t#,

    and sectra$ o'er o! $i"#t. Usin" t#e rinci$es de5e$oed in t#e re5ious section, it is

    ossi%$e to do t#is in an9 'a9s. Lasers and LE3s can %e used to create $i"#t at seci!ic'a5e$en"t#s and o'ers. Lenses, irrors, and !i%er otics can %e used to direct $i"#t.

    3i!!raction "ratin"s and eta$ons are e:a$es o! 'a9s to contro$ t#e 'a5e$en"t#. +ina$$9,

    5arious detectors can %e used to easure $i"#t roerties.

    Creating Light

    W#en 'e t#ink o! arti!icia$ $i"#t sources, t#e !irst t#in" t#at coes to ind is ro%a%$9 a$i"#t %u$%. Li"#t %u$%s "i5e o!! inco#erent $i"#t o5er a 'ide ran"e o! 'a5e$en"t#s.

    7eatin" eta$ !i$aents creates $i"#t in standard $i"#t %u$%s. W#en seci!ic 'a5e$en"t#s

    or co#erent $i"#t is reuired, $asers or LE3-s are t#e usua$ et#od.

    Lasers 7i"#t4$i!ication %9 1tiu$atedEission o!2adiationLasers roduce co#erent e$ectroa"netic 'a5es at narro' 'a5e$en"t# %ands, eit#er

    continuous$9 or u$sed. @#ere are t#ree arts to a $aserD "ain ediu, u, and!eed%ack. @#e %asic idea %e#ind a $aser is t#at !irst atos in t#e "ain ediu are e:cited

    to #i"#er t#an usua$ ener"9 states. *nce enou"# atos are e:cited, a #oton causes t#e

    to dro to a $o'er ener"9 state. In "oin" !ro a #i"#er ener"9 state to a $o'er ener"9state, t#e atos "i5e o!! anot#er #oton at a seci!ic 'a5e$en"t#. @#ese #otons cascade

    t#rou"#out t#e ediu %et'een irrors, causin" ore t#e rocess to continua$$9 reeat.

    +ina$$9, one o! t#e irrors 'i$$ #a5e on$9 artia$ re!$ection, a$$o'in" a %ea to e:it t#e

    ca5it9 Bsee !i"ure 2.1. Lasers #a5e t#e otentia$ to #a5e 5er9 #i"# o'er, and cou$d %edan"erous i! roer sa!et9 recautions are not used. =endi: ) %reaks do'n t#e t9es

    o! $asers into c$assi!ications %ased on o'er and otentia$ #ar!u$ness.

    Figure +.1 &i$i!ied dia"ra o! a Ru%9 $aser. Ru%9 B=$2*) Cr is t#e "ain ediu $as are used to

    u t#e ru%9 to an e:cited state 'it# irrors on eit#er end o! t#e ca5it9.

    Lasers are c$assi!ied accordin" to t#e ediu t#at is %ein" e:cited. @#e t#ree %asic

    cate"ories are so$id Bi&e&Ru%9, "as Bi&e&7e;

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    deterines t#e 'a5e$en"t# t#at t#e $aser roduces. 6ain edius can %e 5er9 di!!erent,

    %ut essentia$$9 t#e9 a$$ need to do t#e sae t#in". +irst, a ou$ation in5ersionQ needs to

    occur. Indi5idua$ atos nora$$9 are !ound in a "round ener"9 state. W#en 1 e$ectron ise:cited and o5es to a di!!erent or%itin" s#e$$, t#e ato #as an o5era$$ #i"#er ener"9

    state. Pou$ation in5ersion occurs '#en t#ere are ore atos in t#e e:cited state t#an t#e

    "round state. =n e:a$e o! a no%$e "as B

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    Figure +.%@#e t#ree ain transitions, stiu$ated a%sor%ance, sontaneous eission, and stiu$ated

    eission.

    &oe atos #a5e etasta%$e states, '#ic# are sta%$e, #i"#;ener"9 states. Metasta%$estates are crucia$ !or $asers %ecause t#e9 a$$o's !or ou$ation in5ersion. 6ain edia is

    $iited to o$ecu$es t#at #a5e etasta%$e states B"enera$$9 a rare occurrence. =s an

    ato "oes !ro t#e etasta%$e state to a $o'er state, it re$eases a #oton 'it# seci!ic'a5e$en"t#. @#ere a9 %e a sa$$ ran"e o! ener"ies at t#e etasta%$e state t#at cause t#e

    $aser to #a5e a ran"e o! 'a5e$en"t#s. 3eendin" on t#e a$ication, t#is can %e eit#er

    %ene!icia$ or not. We 'i$$ see $ater in t#is c#ater #o' to aniu$ate 'a5e$en"t#s.

    Pro%a%$9 t#e %est 'a9 to understand #o' $asers 'ork is to $ook at an aniation !ro oneo! t#e 'e%sites $isted in aendi: 4, #o'e5er !i"ure 2. "i5es a "enera$ o5er5ie' o! t#e

    rocess. = $ist o! soe a5ai$a%$e $asers and t#eir 'a5e$en"t#s is $isted in aendi: 2.

    18

    &ontaneous Eission

    #oton

    6round &tate

    E:cited &tate

    &tiu$ated Eission

    6round &tate

    E:cited &tate

    Ener"9@ransissions

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    Figure +.) &tes in creatin" a $aser. @#e "ra9 dots reresent atos as t#e9 tra5e$ !ro natura$$9 occurrin"

    "round states, to #i"#er etasta%$e states '#en stiu$ated %9 #otons. @#is !i"ure is si$i!ied !or c$arit9.

    In actua$it9, eac# ato %ein" stiu$ated reuires 1 #oton, '#ereas on$9 1 #oton tota$ is s#o'n in t#is

    dia"ra. @#e #otons %ounce %ack and !ort# %et'een t#e surroundin" irrors Bnot s#o'n, a$$o'in" t#e

    stiu$ated eission to continue. @#e odd ato t#at 'ent to a #i"#er state is a rare occurrence it is s#o'n#ere to si$9 to i$$ustration '#at can #aen.

    =s entioned %e!ore, $asers can %e eit#er u$sed or continuous. Pu$sed $asers #a5e a

    $iit to #o' s#ort t#e9 can %e %ased on t#e 7eisen%er" Uncertaint9 Princi$e, '#ic# is

    stated as !o$$o'sD

    4hEt B2.1

    '#ere tis t#e u$se duration, Eis t#e ener"9 Bree%erE

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    11 0010.0.1//// +=+ cmcm 1////.010 c;1

    =

    +=

    010.1////

    1

    .1////

    111

    0.0000)8 n

    ==

    nm

    m7c

    22

    10

    1

    0000)8.0

    /00

    $.) #

    @#e $en"t# o! t#e u$se is Nust seed o! sound u$ti$ied %9 t#e u$se durationD

    [ ] [ ]

    ==

    ns

    sns

    smxtc7 55ulse

    8

    10

    1H10H10)H 0 #

    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    !

    LE3s 7i"#tEittin"=iodes

    LE3s are sii$ar to $asers, #o'e5er t#e9 use on$9 sontaneous eission rat#er t#an

    stiu$ated. Reo5in" t#e irrors !ro a $aser "ets rid o! t#e stiu$ated eission. @#e

    ain di!!erence t#ere!ore %et'een $asers and LE3s is t#at LE3s roduce inco#erent$i"#t. &ince LE3s are ore e!!icient t#an $i"#t %u$%s, and $ess #ar!u$ to t#e #uan e9e

    t#en $asers, LE3s #a5e !ound an9 ractica$ a$ications suc# as %rake $i"#ts and sto

    $i"#ts.

    6irecting Light

    *nce 'e #a5e $i"#t !ro a $i"#t source, 'e need to %e a%$e to accurate$9 contro$ '#ere ittra5e$s. @#ere are se5era$ 'a9s to do t#is. Lenses can %e used to co$$iate or !ocus $i"#t.

    Mirrors are used to re!$ect $i"#t. +ina$$9, !i%er otic ca%$es are 5er9 use!u$ !or

    trans!errin" $i"#t to seci!ic $ocations.

    LensesLenses can %e used to eit#er !ocus or co$$iate $i"#t. = $ens can %e conca5e, con5e:, or

    co%inations o! t#e 2. Co$$iated $i"#t coin" in t#rou"# a conca5e $ens 'i$$ !ocus att#e !oca$ $en"t# Bf. In "enera$, t#e 6aussian $ens !oru$a isD

    =+fss io

    111B2.)

    and t#e a"ni!ication !ro t#e $ens isD

    o

    i

    s

    s-= B2.4

    20

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    Figure +.(3ia"ra !or 6aussian $ens !oru$aD B1so B1si B1!

    Figure +. Lens secia$ case, a oint source at t#e !oca$ $en"t# co$$iates $i"#t. = oint source not on t#ecenter $ane B9et sti$$ at t#e !oca$ $en"t# 'i$$ co$$iate t#e $i"#t at an an"$e to t#e center $ane.

    Figure +.,=n ia"e at t'ice t#e !oca$ $en"t# 'i$$ "i5e 1D1 ia"in".

    @#e +;nu%er Bre!erred to asD +V or +V in industr9 o! a $ens isf;d, as s#o'n in !i"ure2.8. *t#er %e#a5iors o! $enses can %e deterined !ro &ne$$-s $a'. =na$9tica$$9, t#is can

    21

    f

    2f

    ;2f "f f

    d

    so

    si

    i;con5e: $ens

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    %e uite ri"orous, #o'e5er "ra#ica$ so$utions or ra9 tracin" so!t'are ro"ras can

    si$i!9 t#e coutationa$ 'ork.

    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    !"xa#ple +.+

    6i5en an LE3 'it# a 100 diaeter eission area, and #a$!;an"$e di5er"ence

    o! 20o, '#at +V $ens 'ou$d 9ou need to #a5e a di5er"ence #a$! an"$e o! a t9ica$$aser ointer, 0.01oG

    4ns6er:+irst ca$cu$ate t#e iniu diaeter o! t#e $ens !ro %asic etendue rinci$esD

    =

    21,22

    21,11 sinsin dd

    ( )( )01.0sin

    20sin10100

    sin

    sin /

    2

    1,2

    21,11

    2

    ox

    d

    d

    =

    =

    0.1/

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    %$urrin" o! t#e ia"e 'i$$ resu$t, '#ic# is kno'n as coa a%erration. +ie$d cur5ature

    occurs '#en a $ens tends to !ocus on a cur5ed, rat#er t#an !$at $ane. W#en ia"e s#aes

    do not actua$$9 corre$ate 'it# t#e actua$ s#ae o! t#e o%Nect, distortion is occurrin".3istortion is usua$$9 increased as t#e o%Nect is $aced !urt#er o!! t#e center a:is. +ina$$9,

    c#roatic a%erration occurs '#en di!!erent 'a5e$en"t#s #a5e di!!erent %e#a5iors t#rou"#

    t#e $ens, causin" di!!erent co$ors to !ocus at di!!erent oints. It is iortant to kno' t#ata$$ o! t#ese a%errations can %e eit#er e$iinated or inii(ed 'it# 5arious tec#niues

    suc# as usin" u$ti$e $enses or t#e use o! as#erica$ irrors.

    Mirrors

    Mirrors are ade 'it# #i"#$9 re!$ecti5e sur!aces. +erat-s rinci$e can %e used to

    deduce t#at t#e re!$ection an"$e is a$'a9s eua$ to t#e incident an"$e. =side !ro !$at

    irrors, ara%o$ic s#aed irrors are coon$9 !ound in otica$ $a%oratories. Para%o$icirrors !ocus $i"#t to a oint.

    +i%ers

    = 5er9 use!u$ too$ in toda9-s otica$ too$%o: is t#e !i%er. +i%ers are essentia$$9 dra'n"$ass Bor soe transarent ediu 'it# a rotecti5e coatin". = sa$e dia"ra o! a

    !i%er is "i5en in !i"ure 2..

    Figure +.$ 3ia"ra o! !i%er otic ca%$e.

    W#en $i"#t is directed into t#e core at sa$$ enou"# an"$es, tota$ interna$ re!$ection 'i$$

    occur %et'een t#e core and c$addin" inter!ace. @#e nuerica$ aerture is t#e sine o! t#ea:iu #a$! an"$e t#at can %e directed at t#e core and tota$ interna$ re!$ection 'i$$ sti$$

    occur Bsee !i"ure 2.10. @#e !o$$o'in" euation can t#ere!ore %e ca$cu$ated !ro &ne$$-$a'D

    22

    21sin claddingcore nnN4 =

    = B2.

    2)

    Core, n1

    C$addin", n2

    u!!er

    Facket

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    Figure +.1- W#en $i"#t is "uided into a !i%er at an an"$e $ess t#en t#e #a$! an"$e, tota$ interna$ re!$ection

    'i$$ occur, iro5in" $i"#t transission.

    W#en t#e diaeter o! t#e !i%er core is sa$$ enou"#, 'a5es on$9 can tra5e$ in one at#.

    @#ese !i%ers are ca$$ed sin"$e;ode !i%ers. =t $ar"er diaeters, 'a5es coin" in at

    di!!erent an"$es can tra5e$ in di!!erent at#s, and are t#ere!ore tered u$ti;ode at#s.@#e nu%er o! odes a !i%er #as can %e deterined !roD

    V odes 2

    .0

    =

    dN4Nm B2./

    3ue to t#e "enera$$9 $on" $en"t#s, attenuation B$oss due to scatterin" and a%sor%ance is acritica$ roert9 !or !i%ers. +i"ure 2.11 s#o's attenuations in deci%e$s er ki$oeter !or a

    coon !i%er ateria$, si$ica. Po'er transission !or t#e $en"t# o! !i%er can %e t#en

    ca$cu$ated.

    10107

    3

    = B2.

    '#ere is t#e $oss in deci%e$s er $en"t#Bdk, and 3is o'er out o5er initia$ o'er.

    =endi: 4 is a roduct data s#eet !or Cornin"-s &M+;28 *tica$ +i%er B&M+ sin"$eode !i%er. 7oe!u$$9 %9 no' ost o! t#e roerties are c$ear.

    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    !"xa#ple +.%

    Usin" !i"ure 2.11, '#at is t#e transission Bratio o! outut to inut intensit9 o! a

    10 k $en"t# o! !i%er at 80 nG =t 10 nG

    4ns6er:+ro t#e !i"ure, at 80 n, t#ere is aro:iate$9 2 dk attenuation $oss,

    10

    10H2

    80 10

    =nm3 14 transission

    at 10n t#ere is aro:iate$9 0.2 dk attenuation $oss

    24

    Core, n1.

    C$addin", n1.48

    Li"#t 'it#in t#is cone

    is "uided a$on" !i%er

    cr

    12

    12

    12.2o

    12

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    10

    10H2.0

    10 10

    =nm3 (0 4transission

    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    !

    Figure +.11 =ttenuation in !used si$ica Bcoon ateria$ o! !i%ers. +roD

    #ttD'''.se.onas#.edu.auteac#in"sc)011e$ecXotB).d!Bro%a%$9 s#ou$d !ind a %etter "ra#

    Controlling 3a7elength

    Man9 ties, it is necessar9 to 'ork 'it# a seci!ic 'a5e$en"t# or to searate $i"#t %9

    'a5e$en"t#. @#is is esecia$$9 use!u$ in sectrosco9 a$ications. @#ere arean9 'a9s to searate 'a5e$en"t#. @#is section 'i$$ descri%e soe o! t#e

    ore strai"#t!or'ard et#odsD di!!raction "ratin"s, eta$ons, and #aronic

    "eneration.

    3i!!raction 6ratin"

    W#en o$9c#roatic $i"#t is directed at a di!!raction "ratin", it is re!$ected as a s#eet.

    @#e 'a5es sread out into t#e s#eet accordin" to 'a5e$en"t#. 3i!!raction "ratin"s areirrors 'it# 5er9 recise "roo5es cut into t#e. +i"ure 2.12 i$$ustrates t#e %e#a5ior o! a

    di!!raction "ratin".

    2

    http://www.spme.monash.edu.au/teaching/msc3011/elec_&_opt(3).pdfhttp://www.spme.monash.edu.au/teaching/msc3011/elec_&_opt(3).pdf
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    Figure +.1+ 3ia"ra o! a di!!raction "ratin". @#e $i"#t is incident at an"$e , and $ea5es at discreet

    an"$es .

    @#e "ratin" euation is as !o$$o's, '#ere mis t#e orderD( ) sinsindm += B2.8

    &o !or di!!erent 'a5e$en"t#s, t#ere are di!!erent an"$es, causin" t#e $i"#t s#eet. =s a

    "enera$ ru$e o! t#u%, t#e ost e!!icient use o! t#e "ratin" occurs around t#e %$a(e

    'a5e$en"t#.

    +orD efficient>?laze?laze 0

    2

    )

    )

    2>

    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    !"xa#ple +.)

    =n in!rared B1. diode $aser #as an eittin" area o! 1 : 1 eittin"

    area. = !oca$ $en"t# $ens is used to co$$iate t#e $aser. @#e %ea isdirected at a 1200 " B"ratin" er i$$ieter "ratin". =t '#at an"$e does t#e

    1storder di!!racted %ea coe %ack to'ards t#e $aser Bt#is is ca$$ed t#e Littro'

    an"$eG4ns6er:

    +irst, ca$cu$ate dD

    [ ] mx&m

    mmmm

    gd 10))8

    10001

    12001 =

    =

    @#en, $u" into t#e "ratin" euationD( ) sinsin +=dm

    kno'in"D = !or Littro' condition, and 1 Border 1 sin2= 2 (%.1(o

    2/

    %$a(e

    incident an"$e

    re!$ected an"$e

    &u%scrits are t#e

    order o! t#e "ratin"

    d

    o

    ;1

    1

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    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    !

    Eta$ons

    =n eta$on can occur '#ene5er t#ere are airs o! !$at $ates searated %9 an otica$$9

    contacted sacer Bsuc# as a $aser ca5it9, or e5en Nust a icroscoe s$ide. 3ue toconstructi5e and destructi5e inter!erence, eta$ons on$9 a$$o' certain 'a5e$en"t#s to %e

    transitted. Man9 ties eta$ons are un'anted, #o'e5er eit#er usin" an"$ed sur!aces or

    s#i!tin" t#e incident $i"#t to an an"$e can e$iinate t#e.

    +ree &ectra$ Ran"e B+&R [ ]Hznd

    c

    2B2.

    n inde: o! re!raction, d distance %et'een ara$$e$ $anes

    +inesse B+ 2

    2

    1

    B2.10

    and'idt# +W7M B!u$$ 'idt# #a$! a: F

    F12B2.11

    Figure +.10 Eta$on dia"ra.

    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    !"xa#ple +.(

    W#at is t#e !ree sectra$ ran"e and +W7M o! a "$ass Bn1. icroscoe s$ide, 1

    'ideG

    4ns6er:

    /101H.1H2 =

    x

    cF12 100 @7(

    [ ]s

    x

    smx

    fcfc

    110100

    10)

    12

    8

    === 0# 2 F89

    2

    +W7M

    +&R

    Wa5e$en"t#

    @ransission

    BO

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    2

    1

    1

    +

    =n

    n2 0.04

    2

    2F

    =

    1

    0./4

    [ ]

    /4.0

    )mm

    F

    F12

    FWH- == %.),% #!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    !

    7aronic 6eneration

    =side !ro searatin" 'a5e$en"t#s 'it# "ratin"s or usin" inter!erence as in eta$ons, it isossi%$e to i: 'a5e$en"t#s to "et ne' 'a5e$en"t#s. @#ese rocesses ust satis!9

    ener"9 and oentu conser5ation B#o'e5er, not #oton conser5ation. +i"ure 2.14

    deonstrations #o' di!!erentia$ and suation i:in" can occur.

    Figure +.1% I$$ustration o! 2ndand )rd#aronic "eneration.

    !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    !"xa#ple +.

    +ourt# #aronic "eneration is i$$ustrated in t#e !i"ure %e$o'. Ca$cu$ate t#e !ina$

    'a5e$en"t# %9 er!orin" an ener"9 %a$ance. =$$ o! t#e inut %eas enter at10/4 n.

    28

    non$inear

    cr9sta$Q

    110/4 n

    210/4 n

    ) )2 n

    Ener"9 a$anceDE

    in E

    out

    &econd 7aronic 6enerationD

    110/4 n

    210/4 n

    ) )2 n

    Ener"9 a$anceD

    Ein Eout

    )21

    hchchc=+

    4)

    hchchc=+

    @#ird 7aronic 6enerationD

    410/4 n ) n

    non$inearcr9sta$Q

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    4ns6er:

    +irst, rea$i(e t#e das#ed $ine a%o5e can de!ine t#e s9ste. @#en, EinEoutD

    out

    hchc

    =

    1

    4

    out2 +(( n#!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    !

    :easuring Light

    *nce 'e !ina$$9 #a5e $i"#t directed in t#e correct direction and at t#e desired 'a5e$en"t#,

    it is usua$$9 iortant to %e a%$e to detect t#e $i"#t. Caeras can %e used !or 5isua$detection, and 5arious ot#er detectors can %e used to easure o'er, 'a5e$en"t#,

    o$ari(ation, and co#erence. @#is section needs ore 'ork

    Conclusion

    In t#is section, 'e #a5e %een introduced to soe o! t#e %asic too$s used in an otics

    $a%orator9. Li"#t %u$%s, $asers, and diodes can %e used to create $i"#t, irrors, $enses,

    and !i%ers can %e used to direct $i"#t. 6ratin"s, eta$ons, and #aronic "eneration are

    'a9s to aniu$ate t#e 'a5e$en"t#. +ina$$9, detectors and caeras are used to easure$i"#t intensit9. 9 no 'a9 #o'e5er did t#is c#ater contain a co$ete $ist o! otica$

    too$s a5ai$a%$e. In t#e ne:t section, otica$ a$ications 'i$$ %e discussed to rea$i(e t#eotentia$ o! t#ese too$s.

    2

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    Appendix 1

    &cienti!ic Units*tics !reuent$9 dea$s 'it# 5er9 $ar"e or 5er9 sa$$ nu%ers Bn, 67(, etc..

    @#ere!ore, it is iortant to %ecoe !ai$iar 'it# t#e &I re!i:esD

    @era @ 1012 Centi c 10;2 Pico 10;12

    6i"a 6 10 Mi$$i M 10;) +eto ! 10;1

    Me"a M 10/ Micro 10;/ =tto = 10;18

    Ki$o k 10)

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    7ere is anot#er descrition t#at re$ates t#e $aser c$assi!ications to coon $aser t9es and o'er $e5e$sD

    C$ass I ; EYEMP@ L=&ER&, considered Tsa!eT !or intra%ea 5ie'in". Aisi%$e %ea.

    Ma:iu o'er $ess t#an 0.4 W. @#is 'i$$ not cause daa"e e5en '#ere t#e entire

    %ea enters t#e e9e and it is %ein" stared at continuous$9.

    C$ass II ; L*W;P*WERE3 AI&ILE BCW *R 7I67 PUL&E R=@E L=&ER&, 'onTt

    daa"e 9our e9e i! 5ie'ed oentari$9. Aisi%$e %ea.

    Ma:iu o'er $ess t#an 1 W !or 7e

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    Appendix % ; =seful 3ebsites

    #ttDscience'or$d.'o$!ra.co#9sicstoics*tics.#t$#ttDicro.a"net.!su.edurier$i"#tandco$orinde:.#t$

    #ttD'''.#o'stu!!'orks.co

    #ttD'e%#9sics.#.sstate.eduNa5airror

    http://scienceworld.wolfram.com/physics/topics/Optics.htmlhttp://www.howstuffworks.com/http://webphysics.ph.msstate.edu/javamirror/http://scienceworld.wolfram.com/physics/topics/Optics.htmlhttp://www.howstuffworks.com/http://webphysics.ph.msstate.edu/javamirror/