Abstract

The decrease in perceived brightness of a foveal test object produced by a peripheral glare source can be accounted for in terms of a veiling luminance produced by stray light falling on the fovea. The same effect can be produced by an artificial patch of veiling luminance superimposed on the test object. The effect of increasing the angle between the glare source and the test object is equivalent to reducing the brightness of the glare source in accordance with the stray light hypothesis. The measured amount of veiling luminance conforms to that found by previous investigators. The changes in brightness that occur immediately following the onset of a peripheral glare source as well as the changes which occur following removal of the glare source can all be accounted for in terms of the veiling luminance produced by stray light falling on the fovea.

© 1953 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. J. F. Schouten and L. S. Ornstein, J. Opt. Soc. Am. 29, 168 (1939).
    [Crossref]
  2. G. A. Fry and M. Alpern, The effect on foveal vision produced by a spot of light on the sclera near the margin of the retina (to be published).
  3. G. A. Fry and M. Alpern, “The effect of veiling luminance upon the apparent brightness of an object” (to be published).
  4. L. L. Holladay, J. Opt. Soc. Am. 12, 271 (1926).
    [Crossref]
  5. W. S. Stiles, Proc. Roy. Soc. (London) B104, 322 (1928–1929).
  6. W. S. Stiles and C. Dunbar, Ilium. Res. Comm. (Great Britain)Tech. paper No. 16, (1935).
  7. G. A. Fry and M. Alpern, Am. J. Optom. 23, 509 (1946).
  8. B. H. Crawford, Proc. Roy. Soc. (London) B134, 283 (1947).
    [Crossref]
  9. A. Ivanoff, Rev. optique 26, 479 (1947).
  10. P. Moon and D. E. Spencer, J. Opt. Soc. Am. 33, 444 (1943).
    [Crossref]
  11. P. Moon and D. E. Spencer, J. Opt. Soc. Am. 35, 233 (1945).
    [Crossref]

1947 (2)

B. H. Crawford, Proc. Roy. Soc. (London) B134, 283 (1947).
[Crossref]

A. Ivanoff, Rev. optique 26, 479 (1947).

1946 (1)

G. A. Fry and M. Alpern, Am. J. Optom. 23, 509 (1946).

1945 (1)

1943 (1)

1939 (1)

1935 (1)

W. S. Stiles and C. Dunbar, Ilium. Res. Comm. (Great Britain)Tech. paper No. 16, (1935).

1926 (1)

Alpern, M.

G. A. Fry and M. Alpern, Am. J. Optom. 23, 509 (1946).

G. A. Fry and M. Alpern, The effect on foveal vision produced by a spot of light on the sclera near the margin of the retina (to be published).

G. A. Fry and M. Alpern, “The effect of veiling luminance upon the apparent brightness of an object” (to be published).

Crawford, B. H.

B. H. Crawford, Proc. Roy. Soc. (London) B134, 283 (1947).
[Crossref]

Dunbar, C.

W. S. Stiles and C. Dunbar, Ilium. Res. Comm. (Great Britain)Tech. paper No. 16, (1935).

Fry, G. A.

G. A. Fry and M. Alpern, Am. J. Optom. 23, 509 (1946).

G. A. Fry and M. Alpern, The effect on foveal vision produced by a spot of light on the sclera near the margin of the retina (to be published).

G. A. Fry and M. Alpern, “The effect of veiling luminance upon the apparent brightness of an object” (to be published).

Holladay, L. L.

Ivanoff, A.

A. Ivanoff, Rev. optique 26, 479 (1947).

Moon, P.

Ornstein, L. S.

Schouten, J. F.

Spencer, D. E.

Stiles, W. S.

W. S. Stiles and C. Dunbar, Ilium. Res. Comm. (Great Britain)Tech. paper No. 16, (1935).

W. S. Stiles, Proc. Roy. Soc. (London) B104, 322 (1928–1929).

Am. J. Optom. (1)

G. A. Fry and M. Alpern, Am. J. Optom. 23, 509 (1946).

Ilium. Res. Comm. (Great Britain) (1)

W. S. Stiles and C. Dunbar, Ilium. Res. Comm. (Great Britain)Tech. paper No. 16, (1935).

J. Opt. Soc. Am. (4)

Proc. Roy. Soc. (London) (2)

B. H. Crawford, Proc. Roy. Soc. (London) B134, 283 (1947).
[Crossref]

W. S. Stiles, Proc. Roy. Soc. (London) B104, 322 (1928–1929).

Rev. optique (1)

A. Ivanoff, Rev. optique 26, 479 (1947).

Other (2)

G. A. Fry and M. Alpern, The effect on foveal vision produced by a spot of light on the sclera near the margin of the retina (to be published).

G. A. Fry and M. Alpern, “The effect of veiling luminance upon the apparent brightness of an object” (to be published).

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 (10)

F. 1
F. 1

Apparatus for investigating the Schouten-Ornstein effect.

F. 2
F. 2

Pattern for investigating the effect of glare sources.

F. 3
F. 3

Pattern for investigating the effect of a patch of veiling luminance.

F. 4
F. 4

Results for subject TH obtained with the stimulus pattern in Fig. 3 showing the effect of varying the luminance of the patch of veiling luminance, e.

F. 5
F. 5

Results obtained by subject GAF with the stimulus pattern shown in Fig. 2. The different curves represent different values of Bc in foot-Lamberts as follows: 1 = 27.9; 2 = 55.8; 3 = 111.7; 4 = 223.4; 5 = 335; 6 = 558; 7 = 1245; 8 = 2350.

F. 6
F. 6

Results obtained by subject TH with the stimulus pattern shown in Fig. 2. The different curves represent different values of Bc in foot-Lamberts as follows: 1 = 6.65; 2 = 16.63; 3 = 33.25; 4 = 66.5; 5 = 166.3; 6 = 332.5; 7 = 665; 8 = 1663; 9 = 3325; 10 = 6650; 11 = 16 630; 12 = 33 250; 13 = 74 100; 14 = 139 900.

F. 7
F. 7

Same data as in Fig. 6 replotted in terms of log V against log Be.

F. 8
F. 8

Values of Bc required to yield a value of unity for V for various values of θ. Data interpolated from the curves in Fig. 7.

F. 9
F. 9

Stimulus pattern employed by Schouten and Ornstein.

F. 10
F. 10

The effect of asynchronous exposure of e and a-b (Fig. 3). Zero on the time scale represents the onset of a and b which are exposed simultaneously for 5σ. The patch of veiling glare (e) is also exposed for 5σ. When e is turned off, b matches a when Bb = 9170 foot-Lamberts.

Tables (5)

Tables Icon

Table I Data for TH obtained with the stimulus pattern in Fig. 3 showing the effect of varying Be. Be and Bb are expressed in foot-Lamberts.

Tables Icon

Table II Data for GAF obtained with the stimulus pattern in Fig. 2 showing the effect of varying θ and Bc on the luminance of b required to make b match a. Luminance of a constant. Bb and Bc are expressed in foot-Lamberts.

Tables Icon

Table III Data for TH obtained with the stimulus pattern in Fig. 2 showing the effect of varying θ and Bc on the luminance of b required to make b match a in brightness. Luminance of a constant. Bb and Bc expressed in foot-Lamberts.

Tables Icon

Table IV Data from Table III expressed in terms of V.

Tables Icon

Table V The effect on V of asynchronous flash (5σ) exposures of e and a-b (see Fig. 3). Be = 5930 foot-Lamberts. Ba constant. Bb varied from one cycle of exposures to the next to obtain a match with a. Bb in foot-Lamberts.

Equations (5)

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

V = ( B b / B a ) 1 .
B e = k 9 B c / θ n ,
E = B c / π ω ,
B e = 22.4 E / θ 2.5 ,
B e = 10 E / θ 2 ,