Adaptive Optics. Adaptive optics for imaging. Adaptive optics to improve. Ocular High order Aberrations (HOA)

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1 Effect of Adaptive Optics Correction on Visual Performance and Accommodation Adaptive optics for imaging Astromomy Retinal imaging Since 977, Hardy et al, JOSA A Since 989, Dreher et al. Appl Opt Susana Marcos, PhD Instituto de Optica, CSIC, Madrid, Spain C.R: None Courtesy of Galactic Center Group, UCLA Courtesy of Austin Roorda, UC, Berkeley Ocular High order Aberrations (HOA) Adaptive optics to improve retinal images Decrease resolution and contrast of fundus images Decrease quality of images projected on the retina Adaptive optics to improve vision Motivation Customized refractive surgery, custom IOLs, contact lenses or ophthalmic lenses aim at correcting high order aberrations In the even that high order aberration correction was achieved, is this relevant to vision? Adaptive Optics

2 First psycophysical measurements with 7.5 c/deg 6 increase 6 nm 9 Td Visual benefit of correction Shown for relatively high luminances Yoon et al. JOSA A Artal et al. JOV 5 cd/m Fixed luminance 55 c/deg Not detectable wo Liang and Williams, JOSA A 997 Thruluminance with relatively large targets Dalimier et al. JOM 7 Change of VA with correction Does high contrast Visual Acuity improve with correction of HOA? How does this depend on target luminance (5.8 cd/m ) and polarity? Is the improvement in visual quality correlated with the improvement optical quality? Marcos, Sawides, Gambra & Dorronsoro; Journal of Vision 8 Adaptive optics system Imagine Eyes MIR5d 5 actuators 5 μm stroke Focus corrector/ Accommodative demand Deformable mirror SLD (87 nm) Pupil camera HS wavefront sensor Minidisplay Imagine Eyes Haso x microlenses Mitshubishi CRT; CRS VISAGE Stimulus generator Visual Optics and Biophotonics Lab. Instituto de Optica, CSIC, Madrid, Spain Adaptive optics correction Wavefront Close loopmeasurement correction correction of HOA Wave Aberration PSF RMS RMS = =.9.7 μm μm RMS (microns),5 AF CD LR NC SB SM LS Subjects Pupil diameter: 6.6 mm Marcos et al., JOV 8

3 correction of HOA RMS (microns),5 Marcos et al., JOV 8 Correction : 7% AF CD LR NC SB SM LS Subjects Volume under MTF Focus shift after HOA correction,8,6, Subjective focus shift: -.5D Best focus adjusted by the subject before and correction,8,6,,, AF SM -,5 -, -,,,5 -,5 -, -,,,5 Marcos et al. JOV 8 Defocus (D) Subjective focus shift: -.9D Visual Acuity vs luminance: Effect of correction,5 AF Example on one subject, Target luminance (cd/m ) Visual Acuity vs luminance: Effect of correction,5 n=7, Target luminance (cd/m ) Marcos et al. JOV 8 Marcos et al. JOV 8 Comparison with previous literature Marcos et al. JOV 8 Effect of -correction on VA NATURAL CORRECTED Marcos et al. JOV 8 5 cd/m; Visual Acuity vs luminance Reversed polarity,5 AF Marcos et al. JOV 8 Example on one subject, Target luminance (cd/m )

4 Visual Acuity vs luminance Comparison with previous literature Effect of contrast polarity on VA (natural aberrations) BoW WoB,5,5,, dilated pupil (6 mm) Marcos et al. JOV 8 Target luminance (cd/m ) Average across eyes Marcos et al. JOV 8. (JOV 8) Westheimer, OVS Ratio VA = WoB/BoW.8 (OVS I).5 (OVS II) Effect of on WoB/BoW ratio Ratio VA WoB/BoW,5 WoB/BoW Without OA With OA No OA OA, Marcos et al. JOV 8 Target Luminance (cd/m) Ratio VA OA/noOA Benefit on VA: Summary.5.5. Marcos et al. JOV 8 Target luminance (cd/m) Dilated pupil Dilated pupil Natural pupil Correlation of optical/visual performance Improvement in optics & vision:correlated Marcos, Sawides, Gambra and Dorronsoro. Journal of Vision 8 Marcos, Sawides, Gambra and Dorronsoro. Journal of Vision 8

5 Effect of on visual performance with real-world targets Subjective quality preference of natural images Familiar face Recognition Facial expression recognition Effect of aberrations on accommodation Rosales et al JOV 6 Are monochromatic aberrations a cue for the direction of accommodation? Wilson et al. JOSA A.. Investigated using Response time (s) Natural Gain Depends on the subject Fernández & Artal JOSA A, 5 Chen et al JOSA A, 6 Effect of aberrations on accommodation Rosales et al JOV 6 Is the accommodative lag (or the accuracy of accommodative response) influenced by the absence or presence- of certain types of HOA? Do the fluctuations of accommodation depend on the presence/absence of HOA? Approaches Conditions () natural aberrations, Simulated targets Allows testing the effect of retinal blur on the accommodative response Adaptive Optics Also allows possible interactions between defocus and accommodationinduced HOA () corrected aberrations (of the unaccommodated state) () adding μm of spherical aberration, () adding - μm of spherical aberration + + Gambra et al. JOV 9 (submitted) (5) - μm of vertical coma. + 5

6 Experiment 6 5 Staircase accommodation test t (sec) Gambra, Sawides, Dorronsoro & Marcos. JOV 9. In press Hz Wavefront sensing Accommodative response Real-time accommodative response LS Gambra et al. JOV 9. In press Correcting HOA aberrations improves accommodation accuracy Inducing Positive Sph Ab. Or Coma increases lag Favorable contribution of negative spherical aberration Accommodative lag & fluctuations Highest lag Accommodative lag & fluctuations Highest Fluctuations Lag (D) Lowest lag (n=5) Gambra et al. JOV 9. In press Lag (D) Fluctuations (D) Lowest Fluctuations (n=5) Gambra et al. JOV 9. In press Conclusions Visual Optics and Biophotonics Lab.- Adaptive optics allows to test relationships between optical and visual performance. Carlos Dorronsoro Enrique Gambra Daniel Pascual Pablo de Gracia.- Correcting aberrations improves visual acuity in most conditions, at least in subjects that experience significant correction..- Aberrations play a role in the accommodative response and fluctuations. Correction of higher order aberrations reduced accommodative lag. Induction of HOA increases fluctuations. Lucie Sawides 6

7 Funding MINISTERIO DE CIENCIA E INNOVACION FIS5-8; PET-6-78; FIS