Analog CMOS design for optical coherence tomography signal detection and processing.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 18269983.
- Also identified by DOI 10.1109/TBME.2007.905402.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
A CMOS circuit was designed and fabricated for optical coherence tomography (OCT) signal detection and processing. The circuit includes a photoreceiver, differential gain stage and lock-in amplifier based demodulator. The photoreceiver consists of a CMOS photodetector and low noise differential transimpedance amplifier which converts the optical interference signal into a voltage. The differential gain stage further amplifies the signal. The in-phase and quadrature channels of the lock-in amplifier each include an analog mixer and switched-capacitor low-pass filter with an external mixer reference signal. The interferogram envelope and phase can be extracted with this configuration, enabling Doppler OCT measurements. A sensitivity of -80 dB is achieved with faithful reproduction of the interferometric signal envelope. A sample image of finger tip is presented.
Medical subject headings
- Image Enhancement
- Image Interpretation, Computer-Assisted
- Signal Processing, Computer-Assisted
- Tomography, Optical Coherence