Transcript 各式光偵測器及其原理介紹

各式光偵測器及其原理介紹
各式光偵測器及其原理介紹
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Detector performance parameters
Photoemissive devices
Vacuum photodiode
Photomultiplier
Multiple quantum well detectors
PN junction detectors
PIN junction detectors
Schottky photodiodes
Phototransistors
Charge-coupled devices (CCD)
Detector performance parameters
Response:
R(  ) 
Detector _ Output
Singal _ Input
R( f ) 
R(0)
(1  4 2 f 2 2 )1 / 2
response time 
modulation frequency f
cut-off frequency fc
fc 
1
2
Sensitivity:
NEP* 
NEP
( Af )1 / 2
( Af )1/ 2
D 
NEP
*
signal-to-noise ratio (S/N)
noise equivalent power (NEP)
specific detectivity
Photoemissive devices
Vacuum photodiode
Photomultiplier
Multiple quantum well detectors
PN junction detectors
PIN junction detectors
Schottky photodiodes
Phototransistors
Charge-coupled devices (CCD)