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PubMed · 15460883

Adaptive-optics ultrahigh-resolution optical coherence tomography.

B Hermann·E J Fernández·A Unterhuber·H Sattmann·A F Fercher·W Drexler·P M Prieto·P Artal
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Abstract

Merging of ultrahigh-resolution optical coherence tomography (UHR OCT) and adaptive optics (AO), resulting in high axial (3 microm) and improved transverse resolution (5-10 microm) is demonstrated for the first time to our knowledge in in vivo retinal imaging. A compact (300 mm x 300 mm) closed-loop AO system, based on a real-time Hartmann-Shack wave-front sensor operating at 30 Hz and a 37-actuator membrane deformable mirror, is interfaced to an UHR OCT system, based on a commercial OCT instrument, employing a compact Ti:sapphire laser with 130-nm bandwidth. Closed-loop correction of both ocular and system aberrations results in a residual uncorrected wave-front rms of 0.1 microm for a 3.68-mm pupil diameter. When this level of correction is achieved, OCT images are obtained under a static mirror configuration. By use of AO, an improvement of the transverse resolution of two to three times, compared with UHR OCT systems used so far, is obtained. A significant signal-to-noise ratio improvement of up to 9 dB in corrected compared with uncorrected OCT tomograms is also achieved.

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Equipment DesignEquipment Failure AnalysisFeedbackHumansOphthalmoscopesOphthalmoscopyRetinaTomography, Optical CoherenceComparative StudyEvaluation StudyJournal ArticleValidation Study

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B Hermann, E J Fernández, A Unterhuber, H Sattmann, A F Fercher, W Drexler, P M Prieto, P Artal. 2004-09-15. Adaptive-optics ultrahigh-resolution optical coherence tomography.. https://doi.org/10.1364/ol.29.002142

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