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Adaptive Optics Visual Simulator (…And Depth of Focus)

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Adaptive Optics Visual Simulator (…And Depth of Focus) Adaptive Optics visual simulator (…and depth of focus) Pablo Artal LABORATORIO DE OPTICA UNIVERSIDAD DE MURCIA, SPAIN 8th International Wavefront Congress, Santa Fe, USA, February 2007 New LO·UM building! Pedro Prieto Diego Ayala Silvestre Manzanera Joe Lindacher Supported by: & Aberration correction with Adaptive Optics Active element Aberrated eye Corrected eye + = + = PhaseVisual manipulation simulation with AO Active element Original eye Modified eye + = + = Using the AO visual simulator to search for sXIII betterdefocus solutions for presbyopia… using phase masks! NO accommodation 1.0 0.8 Strehl 0.6 0.4 0.2 0.0 0 1 2 3 4 Defocus (D) Adding 1.0 0.8 Strehl phase mask 0.6 0.4 0.2 0.0 0 1 2 3 4 Defocus (D) SpectraAdaptive of Zernike modes with opticsand without paralyzed VISUALaccommodation SIMULATOR for 4.7 mm pupil Interactive design/testing of new ophthalmic devices Presbyopic corrector design procedure Phase profile design Prototype implementation Clinical testing Mass production Presbyopic corrector design procedure Phase profile design Adaptive optics visual simulator Prototype implementation Clinical testing Mass production Visual E testin Stimuli g generator ? Subject Spatial light modulator H-S Induced phase Active element: Liquid crystal programmable phase modulator Hamamatsu X8627 Advantages against deformable mirrors: _ High fidelity: no need of close-loop operation _ No continuity constrains: steep phase changes allowed _ High phase range (ideal for presbyopic zones) Adaptive Optics Visual Simulator Cold mirror Hartmann-Shack Modulator Pupil CCD camera Induced phase Polarizer LASER 633 nm Spatial Focus / vergence filter control Diode laser Pupil 780 nm Stimuli Generator Beam splitter E Subject Aberration measurement and coupling Cold mirror studies Hartmann-Shack Modulator Pupil CCD camera Induced phase Polarizer LASER 633 nm Spatial Focus / vergence filter control Diode laser Pupil 780 nm Stimuli Generator Beam splitter E Subject Objective estimation of depth of focus Cold mirror Hartmann-Shack Modulator Pupil CCD camera Induced phase Polarizer LASER 633 nm Spatial Focus / vergence filter control Pupil 0 Dp Beam splitter 1.4 Dp 2.8 Dp Subject Objective estimation of depth of focus Cold mirror Bifocal profile Hartmann-Shack 1.0 Modulator 0.8 Theoretical Experimental Pupil 0.6 CCD camera Induced phase 0.4 Polarizer Strehl 0.2 LASER Trifocal profile 633 nm 1.0 0.0 0 1 2 3 0.8 Theoretical Spatial Experimental DefocusFocus (Dp) / vergence filter control 0.6 Pupil 0.4 Strehl 0.2 0 Dp Beam 0.0 splitter 0 1.4 1Dp 2 3 Defocus 2.8(Dp) Dp Subject LO·UM_AO_visual PHASE simulatorDESIGN SOFTWARE GRAY-LEVEL IMAGE RELAY- VISUAL OPTICS TESTING SLM smile Subjective depth of focus Cold mirror Hartmann-Shack Modulator Pupil CCD camera Induced phase Polarizer LASER 633 nm Spatial Focus / vergence filter control Diode laser Pupil 780 nm Stimuli Generator Beam splitter E Subject Depth of focus with different phase profiles 22 20 no phase 18 phase A phase B 16 14 12 10 'x' 8 E size 6 (min) 4 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 Defocus (D) The best phases can be manufactured as contact lenses… Prototype checking E AOVS ON E AOVS OFF Prototype checking 2.4 mm pupil 3.6 mm pupil 0.25 0.25 0.20 0.20 0.15 0.15 0.10 0.10 (1/min) 0.05 0.05 Subject: PA Subject: PA Reading perform. 0.00 0.00 0 1 2 3 0 1 2 3 Estimulus vergence (D) Stimulus vergence (Dp) Good agreement Phase on actual contact lens ! Phase produced by the PPM in the AO system Conclusions · Adaptive Optics used as simulator is a powerful tool to better understand how optics affects vision and to develop new and improved ophthalmic solutions · In particular, we have demonstrated its potential to evaluate the depth of focus of different phase profiles to correct presbyopia Conclusions · The performance predicted with the AO system and that obtained with actual lenses were in quite a good agreement · This AO approach can save several steps in current procedures for contact lens design and eventually lead to improved visual solutions .
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