Ultralong-range phase imaging with orthogonal dispersive spectral-domain optical coherence tomography

Area of Science:

• Optics and Photonics
• Biomedical Imaging
• Spectroscopy

Background:

• Spectral-domain optical coherence tomography (SDOCT) is a key imaging modality.
• Improving spectral resolution and imaging depth in SDOCT systems remains a significant challenge.

Purpose of the Study:

• To develop an orthogonal dispersive SDOCT system with enhanced spectral resolution and extended imaging depth.
• To demonstrate the system's capability for quantitative phase imaging.

Main Methods:

• Utilized a spectrometer combining a virtually-imaged phased array (VIPA) and a diffraction grating for 2D dispersion.
• Employed a 2D CCD camera for spectral acquisition.
• Integrated the spectrometer into an SDOCT system.

Main Results:

• Achieved ultrahigh spectral resolution of 0.002 nm over a 50 nm free spectrum range.
• Realized a spectral sampling rate up to ~10^5.
• Demonstrated an imaging depth exceeding 80 mm, the longest reported for SDOCT.
• Obtained a high signal-to-noise ratio.
• Successfully performed quantitative phase imaging of optical components.

Conclusions:

• The developed orthogonal dispersive SDOCT system offers superior spectral resolution and imaging depth.
• This advancement enables high-performance SDOCT imaging and quantitative phase analysis.