Gullstrand Eye Model: Difference between revisions

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== Methods ==
== Methods ==
We did ray tracing in CISET. The data from ray tracing was ported to ISET, from which we could plot the resulting image and do analysis on the sensor image. Using this method, we measured various characteristics of the eye such as the spherical aberration, chromatic aberration, and linespread function.
We extracted values for the Gullstrand eye model from Navarro's 1985 paper, and built a CISET lens with these values. We did ray tracing in CISET, and varied index of refraction as a function of wavelength manually in the code since the lens data file can only accommodate the aberration-free model. The data from ray tracing was ported to ISET, from which we could plot the resulting image and do analysis on the sensor image. Using this method, we measured various characteristics of the eye such as the spherical aberration, chromatic aberration, and linespread function.


== Results ==
== Results ==
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== Conclusions ==
== Conclusions ==
Based on the results we measured, we concluded that the Gullstrand eye model in CISET correlated fairly well with the Navarro Gullstrand model.
== Future Work ==
Based on the results we measured, we concluded that the Gullstrand eye model in CISET correlated fairly well with the Navarro Gullstrand model.
Based on the results we measured, we concluded that the Gullstrand eye model in CISET correlated fairly well with the Navarro Gullstrand model.


== Appendix ==
== Appendix ==
[[File:gullstrand.zip]] gullstrand.dat lens file for integrating into CISET
[[File:gullstrand.zip]] gullstrand.dat lens file for integrating into CISET

Revision as of 20:04, 11 December 2015

Introduction

Background

Methods

We extracted values for the Gullstrand eye model from Navarro's 1985 paper, and built a CISET lens with these values. We did ray tracing in CISET, and varied index of refraction as a function of wavelength manually in the code since the lens data file can only accommodate the aberration-free model. The data from ray tracing was ported to ISET, from which we could plot the resulting image and do analysis on the sensor image. Using this method, we measured various characteristics of the eye such as the spherical aberration, chromatic aberration, and linespread function.

Results

Comparison of LSA of our Gullstrand eye model in CISET versus data from Navarro's 1985 paper.

Comparison of linespread function and chromatic aberration of our Gullstrand eye model in CISET versus the actual human linespread function and data from Navarro's 1985 paper. The linespread functions are pretty comparable, and the chromatic aberration of our lens follows similar trends as modeled by Navarro.

Comparison of polychromatic PSF of our Gullstrand eye model as a function of aperture in CISET versus data from Navarro's 1985 paper. We also see that smaller aperture leads to a sharper PSF. However, we're not sure why the larger aperture does not allow more overall light through the lens in either model.

Comparison of the effects of defocus on the polychromatic MTF of our Gullstrand eye model in CISET versus data from Navarro's 1999 paper. The line in red is our sensor defocused, which has a similar characteristic to Navarro's defocused model.

Conclusions

Based on the results we measured, we concluded that the Gullstrand eye model in CISET correlated fairly well with the Navarro Gullstrand model.

Future Work

Based on the results we measured, we concluded that the Gullstrand eye model in CISET correlated fairly well with the Navarro Gullstrand model.

Appendix

File:Gullstrand.zip gullstrand.dat lens file for integrating into CISET