Accounting for Focal Shift in the Shack-Hartmann Wavefront Sensor

Overview

Journal Opt Lett

Specialty Ophthalmology

Date 2019 Aug 30

PMID 31465350

Citations 14

Authors

Vyas Akondi

Alfredo Dubra

Affiliations

Soon will be listed here.

Abstract

The Shack-Hartmann wavefront sensor samples a beam of light using an array of lenslets, each of which creates an image onto a pixelated sensor. These images translate from their nominal position by a distance proportional to the average wavefront slope over the corresponding lenslet. This principle fails in partially and/or non-uniformly illuminated lenslets when the lenslet array is focused to maximize peak intensity, leading to image centroid bias. Here, we show that this bias is due to the low Fresnel number of the lenslets, which shifts the diffraction focus away from the geometrical focus. We then demonstrate how the geometrical focus can be empirically found by minimizing the bias in partially illuminated lenslets.

Citing Articles

Quantification of optical lensing by cellular structures in the living human eye.

Bedggood P, Ding Y, Dierickx D, Dubra A, Metha A Biomed Opt Express. 2025; 16(2):473-498.

PMID: 39958845 PMC: 11828430. DOI: 10.1364/BOE.547734.

Ultrafast adaptive optics for imaging the living human eye.

Liu Y, Crowell J, Kurokawa K, Bernucci M, Ji Q, Lassoued A Nat Commun. 2024; 15(1):10409.

PMID: 39613735 PMC: 11607088. DOI: 10.1038/s41467-024-54687-z.

Statistical optimal parameters obtained by using clinical human ocular aberrations for high-precision aberration measurement.

Yue X, Yang Y, Chen S, Dai H Int Ophthalmol. 2024; 44(1):292.

PMID: 38940969 DOI: 10.1007/s10792-024-03176-9.

Evolution of adaptive optics retinal imaging [Invited].

Williams D, Burns S, Miller D, Roorda A Biomed Opt Express. 2023; 14(3):1307-1338.

PMID: 36950228 PMC: 10026580. DOI: 10.1364/BOE.485371.

Quantitative Phase Imaging: Recent Advances and Expanding Potential in Biomedicine.

Nguyen T, Pradeep S, Judson-Torres R, Reed J, Teitell M, Zangle T ACS Nano. 2022; 16(8):11516-11544.

PMID: 35916417 PMC: 10112851. DOI: 10.1021/acsnano.1c11507.

References

Pfund J, Lindlein N, Schwider J . Dynamic range expansion of a Shack-Hartmann sensor by use of a modified unwrapping algorithm. Opt Lett. 2007; 23(13):995-7. DOI: 10.1364/ol.23.000995. View

Zou W, Qi X, Burns S . Woofer-tweeter adaptive optics scanning laser ophthalmoscopic imaging based on Lagrange-multiplier damped least-squares algorithm. Biomed Opt Express. 2011; 2(7):1986-2004. PMC: 3130583. DOI: 10.1364/BOE.2.001986. View

Rha J, Jonnal R, Thorn K, Qu J, Zhang Y, Miller D . Adaptive optics flood-illumination camera for high speed retinal imaging. Opt Express. 2009; 14(10):4552-69. DOI: 10.1364/oe.14.004552. View

Yoon G, Pantanelli S, Nagy L . Large-dynamic-range Shack-Hartmann wavefront sensor for highly aberrated eyes. J Biomed Opt. 2006; 11(3):30502. DOI: 10.1117/1.2197860. View

Levine B, Martinsen E, Wirth A, Jankevics A, Toledo-Quinones M, Landers F . Horizontal Line-of-Sight Turbulence Over Near-Ground Paths and Implications for Adaptive Optics Corrections in Laser Communications. Appl Opt. 2008; 37(21):4553-60. DOI: 10.1364/ao.37.004553. View

Doble N, Miller D, Yoon G, Williams D . Requirements for discrete actuator and segmented wavefront correctors for aberration compensation in two large populations of human eyes. Appl Opt. 2007; 46(20):4501-14. PMC: 2654185. DOI: 10.1364/ao.46.004501. View

Sheppard C, Torok P . Focal shift and the axial optical coordinate for high-aperture systems of finite Fresnel number. J Opt Soc Am A Opt Image Sci Vis. 2003; 20(11):2156-62. DOI: 10.1364/josaa.20.002156. View

Tabernero J, Artal P . Optical modeling of a corneal inlay in real eyes to increase depth of focus: optimum centration and residual defocus. J Cataract Refract Surg. 2011; 38(2):270-7. DOI: 10.1016/j.jcrs.2011.07.040. View

Mira-Agudelo A, Lundstrom L, Artal P . Temporal dynamics of ocular aberrations: monocular vs binocular vision. Ophthalmic Physiol Opt. 2009; 29(3):256-63. DOI: 10.1111/j.1475-1313.2009.00655.x. View

10.

Hermann B, Fernandez E, Unterhuber A, Sattmann H, Fercher A, Drexler W . Adaptive-optics ultrahigh-resolution optical coherence tomography. Opt Lett. 2004; 29(18):2142-4. DOI: 10.1364/ol.29.002142. View

11.

Hammer D, Ferguson R, Bigelow C, Iftimia N, Ustun T, Burns S . Adaptive optics scanning laser ophthalmoscope for stabilized retinal imaging. Opt Express. 2009; 14(8):3354-67. PMC: 2923468. DOI: 10.1364/oe.14.003354. View

12.

Mansell J, Hennawi J, Gustafson E, Fejer M, Byer R, Clubley D . Evaluating the effect of transmissive optic thermal lensing on laser beam quality with a shack-hartmann wave-front sensor. Appl Opt. 2008; 40(3):366-74. DOI: 10.1364/ao.40.000366. View

13.

Booth M . Adaptive optics in microscopy. Philos Trans A Math Phys Eng Sci. 2007; 365(1861):2829-43. DOI: 10.1098/rsta.2007.0013. View

14.

Bara S . Measuring eye aberrations with Hartmann-Shack wave-front sensors: should the irradiance distribution across the eye pupil be taken into account?. J Opt Soc Am A Opt Image Sci Vis. 2003; 20(12):2237-45. DOI: 10.1364/josaa.20.002237. View

15.

Bahk S, Rousseau P, Planchon T, Chvykov V, Kalintchenko G, Maksimchuk A . Generation and characterization of the highest laser intensities (10(22) W/cm2). Opt Lett. 2005; 29(24):2837-9. DOI: 10.1364/ol.29.002837. View

16.

Liang J, Williams D, Miller D . Supernormal vision and high-resolution retinal imaging through adaptive optics. J Opt Soc Am A Opt Image Sci Vis. 1997; 14(11):2884-92. DOI: 10.1364/josaa.14.002884. View

17.

Schwarz C, Prieto P, Fernandez E, Artal P . Binocular adaptive optics vision analyzer with full control over the complex pupil functions. Opt Lett. 2011; 36(24):4779-81. DOI: 10.1364/OL.36.004779. View

18.

Zhang Y, Poonja S, Roorda A . MEMS-based adaptive optics scanning laser ophthalmoscopy. Opt Lett. 2006; 31(9):1268-70. DOI: 10.1364/ol.31.001268. View

19.

Hofer H, Artal P, Singer B, Aragon J, Williams D . Dynamics of the eye's wave aberration. J Opt Soc Am A Opt Image Sci Vis. 2001; 18(3):497-506. DOI: 10.1364/josaa.18.000497. View

20.

van Dam M, Le Mignant D, Macintosh B . Performance of the Keck Observatory adaptive-optics system. Appl Opt. 2004; 43(29):5458-67. DOI: 10.1364/ao.43.005458. View