Stokes polarimeter based endoscopes are emerging as an area of technology where polarization imaging can greatly impact clinical care by improving diagnostic tools without the use of exogenous contrast. Image acquisition in minimally invasive surgical settings is often beset by inherently limited illumination. A comprehensive analysis of how signal-to-noise (SNR) propagates through Stokes polarimetric outcomes such as degree of linear polarization (DoLP) and angle of polarization (AoP) in low light is important for future interpretation of data acquired in low-light conditions. A previously developed theoretical model of quantitative polarized light imaging (QPLI) analysis described SNR as a function of both incident light intensity and DoLP. When polarized light interacts with biological tissues, the resultant DoLP of exiting light is dependent on the underlying tissue microstructure. Therefore, in this study we explore how low light impacts SNR of QPLI outcomes of DoLP and AoP differently in tissue phantoms of varying microstructures. Data are compared to theoretical solutions of SNR of DoLP and AoP. Tissues were additionally loaded to varying magnitudes of strain to investigate how variable SNR affects the ability to discern dynamic realignment in biological tissues. We observed a high degree of congruency between experimental and theoretical data, with SNR depending on both light intensity and DoLP. Additionally, we found that AoP may have a greater resilience to noise overall than DoLP and, as such, may be particularly useful in conditions where light is inherently limited.
Recent advancements in nanofabrication technology has led to commercialization of single-chip polarization and color-polarization imaging sensors in the visible spectrum. Novel applications have arisen with the emergence of these sensors leading to questions about noise in the reconstructed polarization images. In this paper, we provide theoretical analysis for the input and output referred noise for the angle and degree of linear polarization information. We validated our theoretical model with experimental data collected from a division of focal plane polarization sensor. Our data indicates that the noise in the angle of polarization images depends on both incident light intensity and degree of linear polarization and is independent of the incident angle of polarization. However, noise in degree of linear polarization images depends on all three parameters: incident light intensity, angle and degree of linear polarization. This theoretical model can help guide the development of imaging setups to record optimal polarization information.
more » « less- Award ID(s):
- 1761561
- NSF-PAR ID:
- 10224519
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- OSA Continuum
- Volume:
- 4
- Issue:
- 5
- ISSN:
- 2578-7519
- Format(s):
- Medium: X Size: Article No. 1461
- Size(s):
- Article No. 1461
- Sponsoring Org:
- National Science Foundation
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