April 2010
Volume 51, Issue 13
Free
ARVO Annual Meeting Abstract  |   April 2010
Adapting to Blur Produced by Ocular High Order Aberrations
Author Affiliations & Notes
  • L. Sawides
    Instituto de Optica, CSIC, Madrid, Spain
  • P. de Gracia
    Instituto de Optica, CSIC, Madrid, Spain
  • C. Dorronsoro
    Instituto de Optica, CSIC, Madrid, Spain
  • E. Gambra
    Instituto de Optica, CSIC, Madrid, Spain
  • M. Webster
    Department of Psychology, University of Nevada, Reno, Nevada
  • S. Marcos
    Instituto de Optica, CSIC, Madrid, Spain
  • Footnotes
    Commercial Relationships  L. Sawides, None; P. de Gracia, None; C. Dorronsoro, None; E. Gambra, None; M. Webster, None; S. Marcos, None.
  • Footnotes
    Support  MICINN FIS2008-02065 and EURYI-05-102-ES (EURHORCs-ESF) to SM; MICINN FPI Predoctoral Fellowship FIS2005-04382 to LS; CSIC JAE-Pre to PdG; CSIC I3P Predoctoral Fellowship to EG; EY-10834 to MW.
Investigative Ophthalmology & Visual Science April 2010, Vol.51, 6347. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      L. Sawides, P. de Gracia, C. Dorronsoro, E. Gambra, M. Webster, S. Marcos; Adapting to Blur Produced by Ocular High Order Aberrations. Invest. Ophthalmol. Vis. Sci. 2010;51(13):6347.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose: : (1) To evaluate the effect of adaptation to High Order Aberrations (HOA). (2) To examine if the adaptation is selective for each subject’s own aberrations.

Methods: : Blur judgements were measured in 4 subjects to images degraded by different amounts of HOA, before (gray screen) and after prior adaptation to images with 5 levels of optical degradation (from sharpest to double the amount of natural blur). A custom-developed Adaptive-Optics (AO) system (provided with an electromagnetic deformable mirror and Hartmann-Shack wavefront sensor) was used to measure and correct the subject’s HOA. A psychophysical channel allowed the presentation of gray-scale images on a CRT monitor viewed through a Badal system (which corrected for spherical error) and the deformable mirror. Each subject viewed 1.98-deg face stimuli degraded by his/her own HOA, as well as by the other subjects’ HOA. Optical blur was generated by convolution of the corresponding PSF with the image, and ranged from diffraction-limit (0×) to 2× the natural HOA of each eye, at 0.05× steps. Adapting images were jittered in time to prevent local light adaptation and presented for 60s at the beginning and 5s between trials. AO-correction and pupil centration were continuously monitored and controlled during the experiment. A 2AFCP (Blur/Sharp) with a QUEST algorithm was used to estimate the subject’s perceived focus point in each condition. The results were analysed in terms of the shift of the perceived focus point before (gray) and after adaptation to sharp, natural and blurred images.

Results: : Natural HOA RMS ranged from 0.18 to 0.39 um (5-mm pupils), and AO correction produced practically diffraction-limited performance. (1) All subjects adapted to the blur imposed by HOA. Adaptation to a sharp image (0×) shifted the perceived focus point toward sharper levels by -0.14±0.04 µm RMS on average, while adapting to a blurred image (1.5× RMS) to more blurred levels by 0.07±0.03 µm on average. The effect is proportional to the amount of blur, with saturation at over ×1.5 RMS blur (except for one subject who showed saturation at 1×). (2) Aftereffect magnitude differed when the subject adapted to their own vs. other subject's HOA. The perceived focus point without prior adaptation differs by less than 0.03 µm on average from that after adaptation to his/her natural aberrations.

Conclusions: : (1) Subjects can adapt to blur produced by ocular HOA, and the effect depends on the amount of blur. (2) Different aftereffects occur when adapting to proper vs. someone else's HOA, suggesting that subjects are adapted to their own natural aberrations.

Keywords: adaptation: blur • aberrations • perception 
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×