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Published on: June 28, 2017
Dynamic-range compression and contrast enhancement in swept-source optical coherence tomography systems with a
Shanshan Liang1, Xinyu Li1, Yao Qin1
1Sun Yat-Sen University, School of Electronics and Information Technology, Guangzhou, China.
Significance:
Optical coherence tomography (OCT) has been widely used in clinical studies. However, the image quality of OCT decreases with increasing imaging depth since the light is rapidly attenuated in biological tissues.
Aim:
We present a compensation approach to preserve weak high-frequency signals from deep structures and compress the dynamic range of the detected signal for superior analog-to-digital conversion and image display capability.
Approach:
A homemade frequency gain compensation amplifier is designed and fabricated to amplify the electrical signal from a balanced photodetector and compensate for the signal attenuation in swept-source OCT (SSOCT).
Results:
It is demonstrated in imaging various objects that this cost-efficient technique effectively enhances the contrast of the deep tissue image.
Conclusions:
A frequency gain compensation amplifier is designed and used to compress the dynamic range of the electrical signal detected by the photodetector of an SSOCT system, which enables weak signals from deep structures to be acquired by the ADC and displayed with enhanced local contrast.
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