TY - JOUR
T1 - Investigation of the impact of water absorption on retinal OCT imaging in the 1060 nm range
AU - Marschall, Sebastian
AU - Pedersen, Christian
AU - Andersen, Peter E.
N1 - This paper was published in Biomedical Optics Express and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://www.opticsinfobase.org/boe/abstract.cfm?URI=boe-3-7-1620. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.
PY - 2012
Y1 - 2012
N2 - Recently, the wavelength range around 1060 nm has become attractive for retinal imaging with optical coherence tomography (OCT), promising deep penetration into the retina and the choroid. The adjacent water absorption bands limit the useful bandwidth of broadband light sources, but until now, the actual limitation has not been quantified in detail. We have numerically investigated the impact of water absorption on the axial resolution and signal amplitude for a wide range of light source bandwidths and center wavelengths. Furthermore, we have calculated the sensitivity penalty for maintaining the optimal resolution by spectral shaping. As our results show, with currently available semiconductor-based light sources with up to 100–120 nm bandwidth centered close to 1060 nm, the resolution degradation caused by the water absorption spectrum is smaller than 10%, and it can be compensated by spectral shaping with negligible sensitivity penalty. With increasing bandwidth, the resolution degradation and signal attenuation become stronger, and the optimal operating point shifts towards shorter wavelengths. These relationships are important to take into account for the development of new broadband light sources for OCT.
AB - Recently, the wavelength range around 1060 nm has become attractive for retinal imaging with optical coherence tomography (OCT), promising deep penetration into the retina and the choroid. The adjacent water absorption bands limit the useful bandwidth of broadband light sources, but until now, the actual limitation has not been quantified in detail. We have numerically investigated the impact of water absorption on the axial resolution and signal amplitude for a wide range of light source bandwidths and center wavelengths. Furthermore, we have calculated the sensitivity penalty for maintaining the optimal resolution by spectral shaping. As our results show, with currently available semiconductor-based light sources with up to 100–120 nm bandwidth centered close to 1060 nm, the resolution degradation caused by the water absorption spectrum is smaller than 10%, and it can be compensated by spectral shaping with negligible sensitivity penalty. With increasing bandwidth, the resolution degradation and signal attenuation become stronger, and the optimal operating point shifts towards shorter wavelengths. These relationships are important to take into account for the development of new broadband light sources for OCT.
U2 - 10.1364/BOE.3.001620
DO - 10.1364/BOE.3.001620
M3 - Journal article
C2 - 22808433
SN - 2156-7085
VL - 3
SP - 1620
EP - 1631
JO - Biomedical Optics Express
JF - Biomedical Optics Express
IS - 7
ER -