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Updated: May 18, 2026

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Published on: October 11, 2016
Characterizing the Coherence of Broadband Sources using Optical Phase Space Contours
A new method uses optical phase-space contours to measure the spatial coherence of broadband light, crucial for optical coherence tomography (OCT). This technique characterizes light sources like superluminescent diodes (SLDs) for improved OCT imaging.
Area of Science:
- Optics and Photonics
- Biomedical Imaging
- Quantum Optics
Background:
- Advances in optical coherence tomography (OCT) necessitate broadband light with precise spatial coherence.
- Characterizing the coherence properties of light sources is essential for optimizing OCT system performance.
Purpose of the Study:
- To present a novel technique for characterizing the coherence properties of broadband light.
- To enable quantitative assessment of longitudinal and transverse coherence and wavefront curvature.
- To compare the performance of a new high-power extended-bandwidth superluminescent diode (SLD) with existing SLDs.
Main Methods:
- Utilizing optical phase-space contours in transverse momentum and position to analyze light coherence.
- Employing a simple heterodyne imaging scheme for direct measurement of phase space distributions.
- Achieving high dynamic range (130 dB) and high sensitivity (0.1 fW) in measurements.
Main Results:
- Demonstrated direct measurement of optical phase-space contours.
- Phase space distributions provide quantitative data on light beam coherence and wavefront curvature.
- Characterized a novel high-power extended-bandwidth SLD, comparing its performance to commercial SLDs.
Conclusions:
- The presented technique offers a robust method for characterizing broadband light coherence.
- This method is vital for the development and optimization of advanced OCT systems.
- The novel SLD shows potential for applications requiring high-power, extended-bandwidth coherent light sources.
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