Visual Acuity and Optical Parameters in Progressive-Power Lenses

@article{Villegas2006VisualAA,
  title={Visual Acuity and Optical Parameters in Progressive-Power Lenses},
  author={Eloy A Villegas and Pablo Artal},
  journal={Optometry and Vision Science},
  year={2006},
  volume={83},
  pages={672-681}
}
Purposes. The purposes of this study are to explore the effect of astigmatism and high-order aberrations of progressive-power lenses (PPLs) on visual acuity (VA) and to find a good optical metric for evaluating visual performance of PPLs. Methods. A Hartmann-Shack (HS) wavefront sensor was used to measure PPLs and human eyes either independently or in combination. An additional channel permits the measurement of VA under the same optical conditions. Measurements were taken in six relevant… Expand
Scoring of Progressive Power Lenses by Means of User Power Maps
TLDR
Although Sheedy's test is an important tool to compare different PPL designs, it cannot be used to compare those designs optimized for improving user power from classical front side designs when power has been measured for both types of designs with a standard focimeter. Expand
Optical performance of progressive addition lenses (PALs) with astigmatic prescription
TLDR
Significant impacts of astigmatic prescription are revealed, providing evidence for the usefulness of four novel optical metrics sensitive to variation of refractive power across the lens surface of PALs in quantifying the optical performance of Pals for patients with astigmatic prescriptions. Expand
Impact of positive coupling of the eye's trefoil and coma in retinal image quality and visual acuity.
TLDR
This work evaluated the relationships among different aberration terms in the human eye-coma, trefoil, and spherical aberration-and their effects on both retinal image quality and visual acuity and found a positive coupling that produces a better retinal images quality than any of the other possible combinations of these terms. Expand
Optical performance of progressive addition lenses (PALs) with astigmatic prescription
The progressive addition lens (PAL) is a spectacle lens design with progressive refractive power changes across the lens surface to provide sharp vision at different viewing distances for patientsExpand
Visual Performance with Lenses Correcting Peripheral Refractive Errors
TLDR
It is possible to design and manufacture lenses to give near-optimum peripheral visual performance to at least ±30° along one visual field meridian, but the benefit is likely to be manifest only if a subject has a considerable relative peripheral refraction, for example, of the order of 2 D. Expand
Measurement and Comparison of Progressive Addition Lenses by Three Techniques
Purpose. To measure and evaluate variations in spherical power, astigmatism and higher-order aberrations (HOAs) in progressive addition lenses (PALs) by three techniques and to compare theirExpand
Characterization of the optical properties of progressive addition lenses (PALs) using root mean square of the power error (RMSPE)
Over the past few decades, progressive addition lenses (PALs) have emerged as an effective correction strategy for presbyopic patients. PALs offer a cosmetic and optical advantage to traditionalExpand
Optical performance of the eye with progressive addition lens correction
The aim of this study was to simulate the retinal image of the eye with progressive addition lens (PAL), correction (without cylindrical component) and investigate its quality. The optical design andExpand
Visual acuity under combined astigmatism and coma: optical and neural adaptation effects.
TLDR
The fact that the expected performance occurs mainly in eyes with no natural astigmatism suggests relevant neural adaptation effects in eyes normally exposed to astigmatic blur. Expand
Comparison of Three Techniques in Measuring Progressive Addition Lenses
TLDR
The three measurement methods are comparable for measuring spherical and cylindrical power across PALs and the non-optical method, CMM, can be used to evaluate the optical properties of a PAL by measuring front and back surface height measurements, although its estimates of HOAs are lower than those from the HSWFS. Expand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 62 REFERENCES
Spatially Resolved Wavefront Aberrations of Ophthalmic Progressive-Power Lenses in Normal Viewing Conditions
  • Eloy A Villegas, P. Artal
  • Physics, Medicine
  • Optometry and vision science : official publication of the American Academy of Optometry
  • 2003
TLDR
A wavefront sensor was designed and built to perform spatially resolved aberration measurements in ophthalmic lenses, in particular in PPL’s, either isolated or in combination with the eye. Expand
Metrics of optical quality derived from wave aberrations predict visual performance.
TLDR
This work presents the correlation of 31 single-value metrics of optical quality to high-contrast visual acuity for 34 conditions where the RMS wavefront error was equal to 0.25 microm over a 6-mm pupil and finds the best metric, called the visual Strehl ratio, accounts for 81% of the variance in high- Contrast logMAR acuity. Expand
Aberrations and retinal image quality of the normal human eye.
  • J. Liang, D. Williams
  • Physics, Medicine
  • Journal of the Optical Society of America. A, Optics, image science, and vision
  • 1997
TLDR
A wave-front sensor is constructed to measure the irregular as well as the classical aberrations of the eye, providing a more complete description of the Eye, indicating that they are not random defects. Expand
Comparison of aberrations in different types of progressive power lenses
  • Eloy A Villegas, P. Artal
  • Mathematics, Medicine
  • Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians
  • 2004
TLDR
Differences in the spatial distribution of the aberrations but not in the global RMS are found, indicating that current PPLs are rather similar to a waterbed, with theAberrations being the water: they can be moved but they cannot be eliminated. Expand
Optical Fourier filtering for whole lens assessment of progressive power lenses
  • T. Spiers, C. Hull
  • Medicine
  • Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians
  • 2000
TLDR
Good qualitative agreement was found between the iso‐cylinder plots provided by the manufacturer and the Fourier filter fringe patterns for the PPLs indicating that optical Fourier filtering provides the ability to map the power distribution across the entire lens aperture without the need for multiple point measurements. Expand
Grating Visual Acuity Testing as a Means of Psychophysical Assessment of Progressive Addition Lenses
  • C. Sullivan, C. Fowler
  • Psychology, Medicine
  • Optometry and vision science : official publication of the American Academy of Optometry
  • 1989
TLDR
A technique previously used for the psychophysical assessment of contact lenses and spectacle lenses is adapted and demonstrated for the measurement of grating visual acuity (VA) through the aspheric portion of PAL's. Expand
Visual instrument image quality metrics and the effects of coma and astigmatism.
  • P. Mouroulis, H. Zhang
  • Mathematics, Medicine
  • Journal of the Optical Society of America. A, Optics and image science
  • 1992
TLDR
This work examines subjective contrast and edge sharpness discrimination in the presence of different amounts of coma, astigmatism, and combinations of these two aberrations and finds that the MTFa correlates with subjective results for all target orientations. Expand
Visual Acuity as a Function of Zernike Mode and Level of Root Mean Square Error
TLDR
Increase the RMS error within any single mode of the normalized Zernike expansion decreases visual acuity in a linear fashion, which means new metrics of the combined effects of the optical and the neural transfer functions that are predictive of visual performance need to be developed. Expand
Optical and retinal factors affecting visual resolution.
TLDR
An improved version of the well-known interference fringe technique which theoretically allows a sinusoidal pattern of very high contrast to be formed directly on the retina to be obtained without prior modification by the optics of the eye is reported. Expand
Adaptive optics visual simulator.
TLDR
The adaptive optics visual simulator is a powerful, non-invasive tool to evaluate how aberrations affect vision and can be used for the interactive design and testing of new ophthalmic devices, and for the simulation of visual outcomes in customized refractive surgery. Expand
...
1
2
3
4
5
...