Abstract

The contrast sensitivity of the visual system to interference fringes has been measured in the range from 10 to 65 cycles/deg with a forced-choice psychophysical procedure. Masking produced by the spatial-noise characteristic of coherent fields was avoided by diluting the interferometric field with a fixed amount of uniform, incoherent light. The loss of contrast sensitivity between 10 and 60 cycles/deg ranged from 0.85 to 1.5 log units depending on the observer. Despite these individual differences, the mean contrast sensitivity for six observers at 60 cycles/deg was more than a factor of 8 higher than the most sensitive previous estimates, suggesting that the neural visual system is much more sensitive to fine detail than previously believed. The most sensitive observer required only 4% contrast to detect a 60-cycle/deg interference fringe. Even the shallow interferometric contrast-sensitivity functions reported here are too steep to be explained solely by scattered light at the retina. It is argued that the optical properties of the photoreceptor mosaic make a negligible contribution to the contrast-sensitivity loss between 0 and 60 cycles/deg, and neural factors must be implicated.

© 1985 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. B. E. A. Saleh, “Optical information processing and the human visual system,” in Applications of Optical Fourier TransformsHenry Stark, ed. (Academic, New York, 1982), pp. 431–463.
    [CrossRef]
  2. Y. Le Grand, “Sur la mesure de l’acuité visuelle au moyen de franges d’interference.” C. R. Acad. Sci. Paris 200, 490–491 (1935).
  3. M. A. Arnulf, M. O. Dupuy, “La transmission des contrastes par le systeme optique de l’oeil et les seuils de contrastes retinines,” C. R. Acad. Sci. Paris 250, 2757–2759 (1960).
  4. F. W. Campbell, D. G. Green, “Optical and retinal factors affecting visual resolution,” J. Physiol. 181, 576–593, (1965).
    [PubMed]
  5. H. Ohzu, “Application of laser in ophthalmology and vision research,” Mem. Sch. Sci. Eng. Wasada Univ. 40, 1–28, (1976).
  6. M. Dressler, B. Rassow, “Neural contrast sensitivity measurements with a laser inteference system for clinical and scientific screening application,” Invest. Ophthalmol. 21, 737–744 (1982).
  7. G. J. Burton, “Evidence for non-linear response processes in the human visual system from measurements on the thresholds of spatial beat frequencies,” Vision Res. 13, 1211–1225 (1972).
    [CrossRef]
  8. D. G. Green, “Visual resolution when light enters the eye through different parts of the pupil,” J. Physiol. (London) 190, 583–593 (1967).
  9. F. Kayazawa, T. Yamamoto, M. Itoi, “Clinical measurement of contrast sensitivity function using laser generated sinusoidal grating,” Jpn. J. Ophthalmol. 25, 229–236 (1981).
  10. D. E. Mitchell, R. D. Freeman, G. Westheimer, “Effect of orientation on the modulation sensitivity for interference fringes on the retina,” J. Opt. Soc. Am. 57, 246–249 (1967).
    [CrossRef] [PubMed]
  11. G. Westheimer, “Modulation thresholds for sinusoidal light distributions on the retina,” J. Physiol. (London) 152, 67–74 (1960).
  12. D. R. Williams, “Aliasing in human foveal vision,” Vision Res. 25, 195–206 (1985).
    [CrossRef] [PubMed]
  13. G. M. Byram, “The physical and photochemical basis of visual resolving power. Part II. Visual acuity and the photochemistry of the retina,” J. Opt. Soc. Am. 34, 718–738 (1944).
    [CrossRef]
  14. F. W. Campbell, J. J. Kulikowski, J. Levinson, “The effect of orientation on the visual resolution of gratings,” J. Physiol. (London) 187, 427–436 (1966).
  15. J. M. Enoch, G. M. Hope, “Interferometric resolution determinations in the fovea and parafovea,” Doc. Ophthalmol. 34, 143–156 (1973).
    [CrossRef] [PubMed]
  16. L. Frisen, M. Frisen, “Simple relationship between the probability distribution of visual acuity and the density of retinal output channels,” Acta Ophthalmol. 54, 437–444, (1976).
    [CrossRef]
  17. L. Frisen, A. Glansholm, “Optical and neural resolution in peripheral vision,” Invest. Ophthalmol. 14, 528–536, (1975).
    [PubMed]
  18. D. G. Green, “Regional variations in the visual acuity for interference fringes on the retina,” J. Physiol. (London) 207, 351–356 (1970).
  19. D. G. Green, “Testing the vision of cataract patients by means of laser-generated interference fringes,” Science 168, 1240–1242 (1970).
    [CrossRef] [PubMed]
  20. D. G. Green, M. M. Cohen, “Laser interferometry in the evaluation of potential macular function in the presence of opacities in the ocular media,” Trans. Am. Acad. Ophthalmol. Otolaryngol. 75, 629–637 (1971).
    [PubMed]
  21. J. Wilson, J. F. B. Hawkes, Optoelectronics: An Introduction (Prentice-Hall, New York, 1983).
  22. Contrast-sensitivity measurements at 50 cycles/deg on observer DG failed to show a reliable difference for horizontal and vertical fringes. Experiments on observer DW showed that field size was not an important parameter for the high spatial frequencies used here, since they can be detected only in the foveal center. Control experiments in which the field was smoothly windowed with a Gaussian aperture also did not affect contrast-sensitivity measurements, suggesting that observers were not using a truncation artifact to detect fringes.
  23. J. Nachmias, R. V. Sansbury, “Grating contrast: discrimination may be better than detection,” Vision Res. 4, 1139–1142 (1974).
  24. The implicit assumption in the correction for this observer is that the masking effect is frequency independent within the range of frequencies from 50 to 65 cycles/deg. Although the data of Figs. 2 and 3 for DW show that this is not strictly true for all observers, the change in masking is probably sufficiently small over this small range of frequencies that it can be ignored.
  25. This experiment does not rule out the possibility that the observer used the moiré pattern (alias) formed between the grating and the cone mosaic to discriminate between horizontal and vertical gratings, although he insisted that the fringe did not appear distorted in the manner of zebra stripes. In any case, it suggests that the observer did not use the color and brightness changes associated with high-contrast interference fringes to detect 60-cycle/deg fringes near threshold.
  26. It may seem that the high-contrast sensitivity to high-frequency interference fringes reported here combined with the known contrast sensitivity to incoherent gratings would yield unreasonably low estimates of the optical quality of the eye. Estimates of optical quality made on a subset of the observers studied here will be given elsewhere. However, preliminary measurements of the incoherent contrast sensitivity of the three most sensitive observers yielded estimates of optical quality falling within the range of estimates from other studies, such as those of Campbell and Green4 and Campbell and Gubisch.27
  27. F. W. Campbell, R. W. Gubisch, “Optical quality of the human eye,” J. Physiol. (London) 186, 558–578 (1966).
  28. A. W. Synder, W. H. Miller, “Photoreceptor diameter and spacing for highest resolving power,” J. Opt. Soc. Am. 67, 696–698 (1977).
    [CrossRef]
  29. W. H. Miller, G. D. Bernard, “Averaging over the foveal receptor aperture curtails aliasing,” Vision Res. 23, 1365–1369 (1984).
    [CrossRef]
  30. G. Osterberg, “Topography of the layer of rods and cones in the human retina,” Acta Ophthalmol. Suppl. 6, 1–103 (1935).
  31. W. H. Miller, “Comparative physiology and evolution of vision in invertebrates,” reprint from Vol VII/6A of Handbook of Sensory Physiology, H. Autrum, ed. (Springer-Verlag, Berlin, 1979), pp. 69–143.
    [CrossRef]
  32. H. Ohzu, J. M. Enoch, “Optical modulation by the isolated human fovea,” Vision Res. 12, 245–251 (1972).
    [CrossRef]

1985 (1)

D. R. Williams, “Aliasing in human foveal vision,” Vision Res. 25, 195–206 (1985).
[CrossRef] [PubMed]

1984 (1)

W. H. Miller, G. D. Bernard, “Averaging over the foveal receptor aperture curtails aliasing,” Vision Res. 23, 1365–1369 (1984).
[CrossRef]

1982 (1)

M. Dressler, B. Rassow, “Neural contrast sensitivity measurements with a laser inteference system for clinical and scientific screening application,” Invest. Ophthalmol. 21, 737–744 (1982).

1981 (1)

F. Kayazawa, T. Yamamoto, M. Itoi, “Clinical measurement of contrast sensitivity function using laser generated sinusoidal grating,” Jpn. J. Ophthalmol. 25, 229–236 (1981).

1977 (1)

1976 (2)

H. Ohzu, “Application of laser in ophthalmology and vision research,” Mem. Sch. Sci. Eng. Wasada Univ. 40, 1–28, (1976).

L. Frisen, M. Frisen, “Simple relationship between the probability distribution of visual acuity and the density of retinal output channels,” Acta Ophthalmol. 54, 437–444, (1976).
[CrossRef]

1975 (1)

L. Frisen, A. Glansholm, “Optical and neural resolution in peripheral vision,” Invest. Ophthalmol. 14, 528–536, (1975).
[PubMed]

1974 (1)

J. Nachmias, R. V. Sansbury, “Grating contrast: discrimination may be better than detection,” Vision Res. 4, 1139–1142 (1974).

1973 (1)

J. M. Enoch, G. M. Hope, “Interferometric resolution determinations in the fovea and parafovea,” Doc. Ophthalmol. 34, 143–156 (1973).
[CrossRef] [PubMed]

1972 (2)

G. J. Burton, “Evidence for non-linear response processes in the human visual system from measurements on the thresholds of spatial beat frequencies,” Vision Res. 13, 1211–1225 (1972).
[CrossRef]

H. Ohzu, J. M. Enoch, “Optical modulation by the isolated human fovea,” Vision Res. 12, 245–251 (1972).
[CrossRef]

1971 (1)

D. G. Green, M. M. Cohen, “Laser interferometry in the evaluation of potential macular function in the presence of opacities in the ocular media,” Trans. Am. Acad. Ophthalmol. Otolaryngol. 75, 629–637 (1971).
[PubMed]

1970 (2)

D. G. Green, “Regional variations in the visual acuity for interference fringes on the retina,” J. Physiol. (London) 207, 351–356 (1970).

D. G. Green, “Testing the vision of cataract patients by means of laser-generated interference fringes,” Science 168, 1240–1242 (1970).
[CrossRef] [PubMed]

1967 (2)

D. G. Green, “Visual resolution when light enters the eye through different parts of the pupil,” J. Physiol. (London) 190, 583–593 (1967).

D. E. Mitchell, R. D. Freeman, G. Westheimer, “Effect of orientation on the modulation sensitivity for interference fringes on the retina,” J. Opt. Soc. Am. 57, 246–249 (1967).
[CrossRef] [PubMed]

1966 (2)

F. W. Campbell, J. J. Kulikowski, J. Levinson, “The effect of orientation on the visual resolution of gratings,” J. Physiol. (London) 187, 427–436 (1966).

F. W. Campbell, R. W. Gubisch, “Optical quality of the human eye,” J. Physiol. (London) 186, 558–578 (1966).

1965 (1)

F. W. Campbell, D. G. Green, “Optical and retinal factors affecting visual resolution,” J. Physiol. 181, 576–593, (1965).
[PubMed]

1960 (2)

M. A. Arnulf, M. O. Dupuy, “La transmission des contrastes par le systeme optique de l’oeil et les seuils de contrastes retinines,” C. R. Acad. Sci. Paris 250, 2757–2759 (1960).

G. Westheimer, “Modulation thresholds for sinusoidal light distributions on the retina,” J. Physiol. (London) 152, 67–74 (1960).

1944 (1)

1935 (2)

Y. Le Grand, “Sur la mesure de l’acuité visuelle au moyen de franges d’interference.” C. R. Acad. Sci. Paris 200, 490–491 (1935).

G. Osterberg, “Topography of the layer of rods and cones in the human retina,” Acta Ophthalmol. Suppl. 6, 1–103 (1935).

Arnulf, M. A.

M. A. Arnulf, M. O. Dupuy, “La transmission des contrastes par le systeme optique de l’oeil et les seuils de contrastes retinines,” C. R. Acad. Sci. Paris 250, 2757–2759 (1960).

Bernard, G. D.

W. H. Miller, G. D. Bernard, “Averaging over the foveal receptor aperture curtails aliasing,” Vision Res. 23, 1365–1369 (1984).
[CrossRef]

Burton, G. J.

G. J. Burton, “Evidence for non-linear response processes in the human visual system from measurements on the thresholds of spatial beat frequencies,” Vision Res. 13, 1211–1225 (1972).
[CrossRef]

Byram, G. M.

Campbell, F. W.

F. W. Campbell, J. J. Kulikowski, J. Levinson, “The effect of orientation on the visual resolution of gratings,” J. Physiol. (London) 187, 427–436 (1966).

F. W. Campbell, R. W. Gubisch, “Optical quality of the human eye,” J. Physiol. (London) 186, 558–578 (1966).

F. W. Campbell, D. G. Green, “Optical and retinal factors affecting visual resolution,” J. Physiol. 181, 576–593, (1965).
[PubMed]

Cohen, M. M.

D. G. Green, M. M. Cohen, “Laser interferometry in the evaluation of potential macular function in the presence of opacities in the ocular media,” Trans. Am. Acad. Ophthalmol. Otolaryngol. 75, 629–637 (1971).
[PubMed]

Dressler, M.

M. Dressler, B. Rassow, “Neural contrast sensitivity measurements with a laser inteference system for clinical and scientific screening application,” Invest. Ophthalmol. 21, 737–744 (1982).

Dupuy, M. O.

M. A. Arnulf, M. O. Dupuy, “La transmission des contrastes par le systeme optique de l’oeil et les seuils de contrastes retinines,” C. R. Acad. Sci. Paris 250, 2757–2759 (1960).

Enoch, J. M.

J. M. Enoch, G. M. Hope, “Interferometric resolution determinations in the fovea and parafovea,” Doc. Ophthalmol. 34, 143–156 (1973).
[CrossRef] [PubMed]

H. Ohzu, J. M. Enoch, “Optical modulation by the isolated human fovea,” Vision Res. 12, 245–251 (1972).
[CrossRef]

Freeman, R. D.

Frisen, L.

L. Frisen, M. Frisen, “Simple relationship between the probability distribution of visual acuity and the density of retinal output channels,” Acta Ophthalmol. 54, 437–444, (1976).
[CrossRef]

L. Frisen, A. Glansholm, “Optical and neural resolution in peripheral vision,” Invest. Ophthalmol. 14, 528–536, (1975).
[PubMed]

Frisen, M.

L. Frisen, M. Frisen, “Simple relationship between the probability distribution of visual acuity and the density of retinal output channels,” Acta Ophthalmol. 54, 437–444, (1976).
[CrossRef]

Glansholm, A.

L. Frisen, A. Glansholm, “Optical and neural resolution in peripheral vision,” Invest. Ophthalmol. 14, 528–536, (1975).
[PubMed]

Green, D. G.

D. G. Green, M. M. Cohen, “Laser interferometry in the evaluation of potential macular function in the presence of opacities in the ocular media,” Trans. Am. Acad. Ophthalmol. Otolaryngol. 75, 629–637 (1971).
[PubMed]

D. G. Green, “Regional variations in the visual acuity for interference fringes on the retina,” J. Physiol. (London) 207, 351–356 (1970).

D. G. Green, “Testing the vision of cataract patients by means of laser-generated interference fringes,” Science 168, 1240–1242 (1970).
[CrossRef] [PubMed]

D. G. Green, “Visual resolution when light enters the eye through different parts of the pupil,” J. Physiol. (London) 190, 583–593 (1967).

F. W. Campbell, D. G. Green, “Optical and retinal factors affecting visual resolution,” J. Physiol. 181, 576–593, (1965).
[PubMed]

Gubisch, R. W.

F. W. Campbell, R. W. Gubisch, “Optical quality of the human eye,” J. Physiol. (London) 186, 558–578 (1966).

Hawkes, J. F. B.

J. Wilson, J. F. B. Hawkes, Optoelectronics: An Introduction (Prentice-Hall, New York, 1983).

Hope, G. M.

J. M. Enoch, G. M. Hope, “Interferometric resolution determinations in the fovea and parafovea,” Doc. Ophthalmol. 34, 143–156 (1973).
[CrossRef] [PubMed]

Itoi, M.

F. Kayazawa, T. Yamamoto, M. Itoi, “Clinical measurement of contrast sensitivity function using laser generated sinusoidal grating,” Jpn. J. Ophthalmol. 25, 229–236 (1981).

Kayazawa, F.

F. Kayazawa, T. Yamamoto, M. Itoi, “Clinical measurement of contrast sensitivity function using laser generated sinusoidal grating,” Jpn. J. Ophthalmol. 25, 229–236 (1981).

Kulikowski, J. J.

F. W. Campbell, J. J. Kulikowski, J. Levinson, “The effect of orientation on the visual resolution of gratings,” J. Physiol. (London) 187, 427–436 (1966).

Le Grand, Y.

Y. Le Grand, “Sur la mesure de l’acuité visuelle au moyen de franges d’interference.” C. R. Acad. Sci. Paris 200, 490–491 (1935).

Levinson, J.

F. W. Campbell, J. J. Kulikowski, J. Levinson, “The effect of orientation on the visual resolution of gratings,” J. Physiol. (London) 187, 427–436 (1966).

Miller, W. H.

W. H. Miller, G. D. Bernard, “Averaging over the foveal receptor aperture curtails aliasing,” Vision Res. 23, 1365–1369 (1984).
[CrossRef]

A. W. Synder, W. H. Miller, “Photoreceptor diameter and spacing for highest resolving power,” J. Opt. Soc. Am. 67, 696–698 (1977).
[CrossRef]

W. H. Miller, “Comparative physiology and evolution of vision in invertebrates,” reprint from Vol VII/6A of Handbook of Sensory Physiology, H. Autrum, ed. (Springer-Verlag, Berlin, 1979), pp. 69–143.
[CrossRef]

Mitchell, D. E.

Nachmias, J.

J. Nachmias, R. V. Sansbury, “Grating contrast: discrimination may be better than detection,” Vision Res. 4, 1139–1142 (1974).

Ohzu, H.

H. Ohzu, “Application of laser in ophthalmology and vision research,” Mem. Sch. Sci. Eng. Wasada Univ. 40, 1–28, (1976).

H. Ohzu, J. M. Enoch, “Optical modulation by the isolated human fovea,” Vision Res. 12, 245–251 (1972).
[CrossRef]

Osterberg, G.

G. Osterberg, “Topography of the layer of rods and cones in the human retina,” Acta Ophthalmol. Suppl. 6, 1–103 (1935).

Rassow, B.

M. Dressler, B. Rassow, “Neural contrast sensitivity measurements with a laser inteference system for clinical and scientific screening application,” Invest. Ophthalmol. 21, 737–744 (1982).

Saleh, B. E. A.

B. E. A. Saleh, “Optical information processing and the human visual system,” in Applications of Optical Fourier TransformsHenry Stark, ed. (Academic, New York, 1982), pp. 431–463.
[CrossRef]

Sansbury, R. V.

J. Nachmias, R. V. Sansbury, “Grating contrast: discrimination may be better than detection,” Vision Res. 4, 1139–1142 (1974).

Synder, A. W.

Westheimer, G.

D. E. Mitchell, R. D. Freeman, G. Westheimer, “Effect of orientation on the modulation sensitivity for interference fringes on the retina,” J. Opt. Soc. Am. 57, 246–249 (1967).
[CrossRef] [PubMed]

G. Westheimer, “Modulation thresholds for sinusoidal light distributions on the retina,” J. Physiol. (London) 152, 67–74 (1960).

Williams, D. R.

D. R. Williams, “Aliasing in human foveal vision,” Vision Res. 25, 195–206 (1985).
[CrossRef] [PubMed]

Wilson, J.

J. Wilson, J. F. B. Hawkes, Optoelectronics: An Introduction (Prentice-Hall, New York, 1983).

Yamamoto, T.

F. Kayazawa, T. Yamamoto, M. Itoi, “Clinical measurement of contrast sensitivity function using laser generated sinusoidal grating,” Jpn. J. Ophthalmol. 25, 229–236 (1981).

Acta Ophthalmol. (1)

L. Frisen, M. Frisen, “Simple relationship between the probability distribution of visual acuity and the density of retinal output channels,” Acta Ophthalmol. 54, 437–444, (1976).
[CrossRef]

Acta Ophthalmol. Suppl. (1)

G. Osterberg, “Topography of the layer of rods and cones in the human retina,” Acta Ophthalmol. Suppl. 6, 1–103 (1935).

C. R. Acad. Sci. Paris (2)

Y. Le Grand, “Sur la mesure de l’acuité visuelle au moyen de franges d’interference.” C. R. Acad. Sci. Paris 200, 490–491 (1935).

M. A. Arnulf, M. O. Dupuy, “La transmission des contrastes par le systeme optique de l’oeil et les seuils de contrastes retinines,” C. R. Acad. Sci. Paris 250, 2757–2759 (1960).

Doc. Ophthalmol. (1)

J. M. Enoch, G. M. Hope, “Interferometric resolution determinations in the fovea and parafovea,” Doc. Ophthalmol. 34, 143–156 (1973).
[CrossRef] [PubMed]

Invest. Ophthalmol. (2)

M. Dressler, B. Rassow, “Neural contrast sensitivity measurements with a laser inteference system for clinical and scientific screening application,” Invest. Ophthalmol. 21, 737–744 (1982).

L. Frisen, A. Glansholm, “Optical and neural resolution in peripheral vision,” Invest. Ophthalmol. 14, 528–536, (1975).
[PubMed]

J. Opt. Soc. Am. (3)

J. Physiol. (1)

F. W. Campbell, D. G. Green, “Optical and retinal factors affecting visual resolution,” J. Physiol. 181, 576–593, (1965).
[PubMed]

J. Physiol. (London) (5)

D. G. Green, “Visual resolution when light enters the eye through different parts of the pupil,” J. Physiol. (London) 190, 583–593 (1967).

F. W. Campbell, J. J. Kulikowski, J. Levinson, “The effect of orientation on the visual resolution of gratings,” J. Physiol. (London) 187, 427–436 (1966).

G. Westheimer, “Modulation thresholds for sinusoidal light distributions on the retina,” J. Physiol. (London) 152, 67–74 (1960).

D. G. Green, “Regional variations in the visual acuity for interference fringes on the retina,” J. Physiol. (London) 207, 351–356 (1970).

F. W. Campbell, R. W. Gubisch, “Optical quality of the human eye,” J. Physiol. (London) 186, 558–578 (1966).

Jpn. J. Ophthalmol. (1)

F. Kayazawa, T. Yamamoto, M. Itoi, “Clinical measurement of contrast sensitivity function using laser generated sinusoidal grating,” Jpn. J. Ophthalmol. 25, 229–236 (1981).

Mem. Sch. Sci. Eng. Wasada Univ. (1)

H. Ohzu, “Application of laser in ophthalmology and vision research,” Mem. Sch. Sci. Eng. Wasada Univ. 40, 1–28, (1976).

Science (1)

D. G. Green, “Testing the vision of cataract patients by means of laser-generated interference fringes,” Science 168, 1240–1242 (1970).
[CrossRef] [PubMed]

Trans. Am. Acad. Ophthalmol. Otolaryngol. (1)

D. G. Green, M. M. Cohen, “Laser interferometry in the evaluation of potential macular function in the presence of opacities in the ocular media,” Trans. Am. Acad. Ophthalmol. Otolaryngol. 75, 629–637 (1971).
[PubMed]

Vision Res. (5)

D. R. Williams, “Aliasing in human foveal vision,” Vision Res. 25, 195–206 (1985).
[CrossRef] [PubMed]

G. J. Burton, “Evidence for non-linear response processes in the human visual system from measurements on the thresholds of spatial beat frequencies,” Vision Res. 13, 1211–1225 (1972).
[CrossRef]

H. Ohzu, J. M. Enoch, “Optical modulation by the isolated human fovea,” Vision Res. 12, 245–251 (1972).
[CrossRef]

W. H. Miller, G. D. Bernard, “Averaging over the foveal receptor aperture curtails aliasing,” Vision Res. 23, 1365–1369 (1984).
[CrossRef]

J. Nachmias, R. V. Sansbury, “Grating contrast: discrimination may be better than detection,” Vision Res. 4, 1139–1142 (1974).

Other (7)

The implicit assumption in the correction for this observer is that the masking effect is frequency independent within the range of frequencies from 50 to 65 cycles/deg. Although the data of Figs. 2 and 3 for DW show that this is not strictly true for all observers, the change in masking is probably sufficiently small over this small range of frequencies that it can be ignored.

This experiment does not rule out the possibility that the observer used the moiré pattern (alias) formed between the grating and the cone mosaic to discriminate between horizontal and vertical gratings, although he insisted that the fringe did not appear distorted in the manner of zebra stripes. In any case, it suggests that the observer did not use the color and brightness changes associated with high-contrast interference fringes to detect 60-cycle/deg fringes near threshold.

It may seem that the high-contrast sensitivity to high-frequency interference fringes reported here combined with the known contrast sensitivity to incoherent gratings would yield unreasonably low estimates of the optical quality of the eye. Estimates of optical quality made on a subset of the observers studied here will be given elsewhere. However, preliminary measurements of the incoherent contrast sensitivity of the three most sensitive observers yielded estimates of optical quality falling within the range of estimates from other studies, such as those of Campbell and Green4 and Campbell and Gubisch.27

B. E. A. Saleh, “Optical information processing and the human visual system,” in Applications of Optical Fourier TransformsHenry Stark, ed. (Academic, New York, 1982), pp. 431–463.
[CrossRef]

W. H. Miller, “Comparative physiology and evolution of vision in invertebrates,” reprint from Vol VII/6A of Handbook of Sensory Physiology, H. Autrum, ed. (Springer-Verlag, Berlin, 1979), pp. 69–143.
[CrossRef]

J. Wilson, J. F. B. Hawkes, Optoelectronics: An Introduction (Prentice-Hall, New York, 1983).

Contrast-sensitivity measurements at 50 cycles/deg on observer DG failed to show a reliable difference for horizontal and vertical fringes. Experiments on observer DW showed that field size was not an important parameter for the high spatial frequencies used here, since they can be detected only in the foveal center. Control experiments in which the field was smoothly windowed with a Gaussian aperture also did not affect contrast-sensitivity measurements, suggesting that observers were not using a truncation artifact to detect fringes.

Cited By

OSA participates in CrossRef's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (5)

Fig. 1
Fig. 1

Components of the field containing interference fringe. Iinc is the retinal illuminance of 630-nm incoherent light. Icoh is the retinal illuminance of 632.8-nm coherent light. ΔIcoh is the amplitude of the cosinusoidal interference fringe. The average retinal illuminance across the field Icoh + Iinc was always 500 Td.

Fig. 2
Fig. 2

Interferometric contrast-sensitivity functions obtained with the coherent fraction of the total retinal illuminance P equal to 100% (filled symbols) and 10% (open symbols). Data are shown for two observers, MD (circles) and DW (squares); field size, 1.5 deg.

Fig. 3
Fig. 3

Contrast threshold as a function of the coherent fraction of the retinal illuminance P for two spatial frequencies, 10 cycles/deg (filled circles) and 50 cycles/deg (open circles). Observer, DW; field size, 1 deg.

Fig. 4
Fig. 4

Forced-choice interferometric contrast sensitivity for six observers between 10 and 65 cycles/deg. The solid line is the modulation transfer function for a circular receptor aperture with a diameter of 0.46 min of arc (2.3 μm). Vertical position of curve is arbitrary. Observers, MD (open diamonds), DG (open circles), PL (filled triangles), LL (filled circles), WM (open squares), and DW (filled squares); field size, 1 deg.

Fig. 5
Fig. 5

Comparison with previous studies. The range of interferometric contrast-sensitivity data shown in Fig. 4 for six observers is represented by the pinstripe area. Observer DG, present study (open circles); observer DG, study of Campbell and Green.4 Dotted line shows second observer (FWC) from Campbell and Green. Arnulf and Dupuy3 (filled squares), mean of three observers; retinal illuminance, 126 Td; wavelength, 546 nm. Burton7 (dashed line), mean of two observers; retinal illuminance, 2950 Td; wavelength, 632.8 nm. Westheimer11 (open squares), mean of three observers; retinal illuminance, 2200 Td; wavelength, 555 nm.

Equations (2)

Equations on this page are rendered with MathJax. Learn more.

C = Δ I coh / ( I coh + I inc ) ,
P = I coh / ( I coh + I inc ) .

Metrics