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B GIO DC V O TOTRNG CAO NG CNG NGH THNH

KHOA IN T-VIN THNG= = = = o0o = = = =

H THNG THNG TIN QUANG

TI: B PHT QUANG

BI TP LN

Gio vin hng dn: L Vn ThnSinh vin thc hin: Nguyn Vn Cng

Nguyn Th Lan

V Linh QuyLp : C in T 1_K3

H Ni 10 - 2008

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Ngun Pht quangNgun Pht quangCC VNG NNG LNG

Qu trnh c bn xy ra gia trng thi nng lng nguyn t

a, Hp Th b, Bc x t pht c, Bc x kch thch

hv

hv

hv

hv

E1 v E2: trng thi t v trng thi kch thch ca ccnguyn t ca mi trng hp th . nh sng ti c tn sv,nng lng photon hv

Nguyn t c kch thch quay v trng thi t v pht ranh sng. Thng qua 2 qu trnh l bc x t pht v bc xkch thch

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Ngun pht quangNgun pht quangTip gip P-N:Hnh thnh t 2 loi bn dn loi n v bn dn loi p:Khi cha t in p phn cc => Cc ht ti asKhuych tn qua lp tip gip => Hnh thnhhng ro thTrng thi cn bng thit lp => Vng ngho(khng c ht ti linh ng)

Vng ngho

P

P

NN

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Ngun pht quangNgun pht quangTip gip P-N: Phn cc ng-c: Vng ngho m rng ra, cc in t

v cc l trng kh gp nhau ti hp pht ra nh

sng.S dng trong photodiode.

Dng ht mang thiu s Bng ho tr

Truyn dn

Pha n Pha p

Vng ngho m rng

Ngun ngoi

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Ngun pht quangNgun pht quangTip gip P-N:

Phn cc thun: Vng ngho hp li hay hng ro ththp xung cc in t v cc l trng -c bm vovng ngho d dng ti hp pht ra nh sng.

Quan h gia dng chy qua tip gip v th t vo

Vng ngho hp li

Ngun ngoi

Pha pPha n

P N

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Ngun pht quangNgun pht quangTip gip P-N:

Cu trc ng th: cc ht ti khng b giam hm hiu sutpht x km.

Cu trc d th kp: gm 3 lpc bn

Lp bn dn mng gia c Eg nh(lp tch cc)

Hai lp bn dn p v n hai bn c Egln hn (cc lp hn ch)

u im:- Giam hm ht ti

- Giam hm photon

Loi n Loi p

bng

truyn dn

bngho tr

Mtnghing

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Ngun pht quangNgun pht quangCu trc LED:

Cu trc d th kp

Da trn c ch pht x tpht

nh sng pht ra l nh sngkhng kt hp c rngph ln (30 - 60 nm)

rng chm sng pht xln Hiu sut ghp nh

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Ngun pht quangNgun pht quangCu trc LED:LED pht mt:

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Ngun pht quangNgun pht quangCu trc LED:LED pht cnh:

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Ngun pht quangNgun pht quangCu trc LED:

p ng ca LED:

-ng c tnh P-I t l theo I

bo ho dng bm cao.

Nhit tng p nggim.

c tnh P-I ca LED:

Dng iu khin(mA)Dng iu khin(mA)

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Ngun pht quangNgun pht quangCu trc LED:

c tnh ph ca LED:Ph ca LED lin quan n ph pht x t pht.

rngph:

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Ngun pht quangNgun pht quangCu trc LASER:Laser: B cng h-ng trong mt mi tr-ng tch cc(khuych i)

Laser bn dn hay LD: cu trc d th kp

Di thanh ngang

Li bn

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Ngun pht quangNgun pht quangCu trc LASER:Qu trnh hi tip quang: thc hin trong mt hp cngh-ng hnh thnh bi 2 g-ng phn x.

phn x:

Ng-ng laser: cc photon sinh rat pht x kch thch b xung cho

cc photon b mt i do suy hao

khuych i quang phi ln

b suy hao hp cng h-ng Hot

ng laser ch xy ra khi dng

bm > dng ng-ng. Tng trung bnh

Gng

Mt tch

Phng x

Phun dng

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Ngun pht quangNgun pht quangCu trc LASER:

. Giam hm dng bm: Dng bm ch chy qua vngtch cc.

. Mt s ph-ng php -c s dng:

- in cc di hp

- Tng in tr sut bng bn ph proton

- To ro cn bng mt lp tip gip p-n phn cc ng-c

- Knh dn bng khuych tn cht pha tp

- iu bin dy lp bn dn

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Ngun pht quangNgun pht quangCu trc LASER:

Mt s v d c th:

Cu trc LD dn sng khuych i:

a,di oxide

b,di tip gip

Cht in mi Khuych tn nh sng

C

ht nnC

ht nn

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Ngun pht quangNgun pht quangCu trc LASER:

Cu trc LD dn sng chit sut

a,dn sng chit sut yu

b,dn sng chit sut mnh

Tip xc Tip xc

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Ngun pht quangNgun pht quangCu trc LASER:Laser phn b hi tip (DFB): Qu trnh hi tip -cthc hin bi nhiu x Bragg ghp cp cc sng lantruyn theo chiu thun ng-c.

Ghp cp ch xy ra i vi mode tho mn iu kinBragg:

Li st

Phng x

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Ngun pht quangNgun pht quangCu trc LASER:c tnh P-I

nh h-ng ca nhit :

cng sut pht x theo nhit:

Dng iu khin(mA)

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THE END !