Phase noise and phase modulation in optical coherence tomography.
The signal in optical coherence tomography is often modulated either in phase or by use of the Doppler modulation generated by a depth-scanning mechanism. The effect of each type of modulation on the signal's amplitude is evaluated. The advantages of each type of modulation in terms of immunity to phase noise and penetration depth are discussed in relation to two envelope detection schemes, i.e., lock-in detection and rms-to-dc conversion. Phase noise due to drifts and demodulation instabilities causes distortion of the signal envelope and can be responsible in part for the speckle appearance of the image.
Parrein
Pascale
P
Center for Research and Education in Optics and Lasers, University of Central Florida, 4000 Central Florida Boulevard, Orlando, Florida 32816-2700, USA. pascale.parrein@cea.fr
Meier
Joachim
J
D000818:Animals; D016477:Artifacts; D019544:Equipment Failure Analysis / Q000379:methods*; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D051379:Mice; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012867:Skin / Q000166:cytology*; D013269:Stochastic Processes; D041623:Tomography, Optical Coherence / Q000295:instrumentation* / Q000379:methods*