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Updated: May 1, 2026
11:21
Integrated Photoacoustic Ophthalmoscopy and Spectral-domain Optical Coherence Tomography
Published on: January 15, 2013
10.9K
Complete complex conjugate resolved heterodyne swept source optical coherence tomography using a dispersive optical
Al-Hafeez Dhalla1, Joseph A Izatt
1Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA.
Biomedical Optics Express
|March 22, 2012
Summary
A dispersive optical delay line (DODL) in swept source optical coherence tomography (SSOCT) does not cause pure phase modulation. Coherence revival, not the DODL, was responsible for phase modulation in prior studies.
Area of Science:
- Biomedical Optics
- Optical Coherence Tomography
- Metrology
Background:
- Previous research incorrectly attributed phase modulation in swept source optical coherence tomography (SSOCT) to a dispersive optical delay line (DODL).
- This erroneous conclusion suggested the DODL enabled complex conjugate artifact removal in Fourier domain OCT through optical heterodyning.
Purpose of the Study:
- To correct a significant error in a prior publication regarding the function of a DODL in SSOCT systems.
- To accurately identify the phenomenon responsible for phase modulation and clarify the role of the DODL.
Main Methods:
- Re-evaluation of experimental observations from a SSOCT system utilizing a DODL.
- Analysis of optical phenomena, specifically distinguishing between DODL-induced effects and coherence revival.
Main Results:
- The dispersive optical delay line (DODL) does not generate pure phase modulation in SSOCT.
- The observed phase modulation was determined to be a result of coherence revival.
- The DODL was confirmed to provide a compact method for achieving significant group delay and adjustable group velocity dispersion compensation.
Conclusions:
- The dispersive optical delay line (DODL) is not the source of phase modulation for complex conjugate artifact removal in Fourier domain OCT.
- Coherence revival is the phenomenon responsible for the phase modulation previously misinterpreted in SSOCT systems.
- The DODL remains a valuable component for group delay and dispersion management in SSOCT systems.
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