Abstract

Depth of focus of the human eye is determined by the loss of resolving power (visual acuity) with increase in out-of-focus blurring of the retinal image. An instrument is described which permits accurate measurement of these phenomena, using psychophysical methods with the checkerboard visual-acuity test chart. All test conditions are held constant, binocular vision is maintained, and time of exposure of the test target is limited to 0.2 second. Depth of focus was measured under the two following conditions: (1) increase in the angular size of the test target, and (2) increase and decrease of pupil size as effected by suitable drugs. With the angular size of the test target equivalent to 20/25 Snellen notation, for three subjects the mean total depth of focus was found to be 0.94 diopter at the 50% level of probable visual resolution of the target details and 0.63 diopter at the estimated 99% level. It was found that for each step of increase in target size (20/25 to 20/30, and so on) the total depth of focus increased by about 0.35 diopter. It was found also that over the range of pupil size from 2.5 to 8.0 mm the total depth of focus decreased about 0.12 diopter per millimeter of increase in the size of the pupil. These results were reviewed with respect to hyperfocal distance.

© 1959 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. F. W. Campbell, “The depth of field of the human eye,” (Great Britain, March, 1954).
  2. J. Adamson and E. F. Fincham, Trans. Ophthalmol. Soc., United Kingdom 59, 163–179 (1939).
  3. K. N. Ogle, “Measurements on the depth of focus of the human eye with various test objects,” (unpublished thesis, Dartmouth College, Hanover, New Hampshire, 1927).
  4. Gunnar von Bahr, Acta Ophthalmol. 30, 39–44 (1952).
  5. Sukeyuki Oshima, Japan. J. Ophthalmol. 2, 63–72 (1958).
  6. “Adjutant General's Office, PRS report No. 742, studies in visual acuity, report of progress,” (Personnel Research Section, Washington, D. C., 1947).
  7. F. L. Dimmick and L. M. Rudolph, “Checkerboard visual acuity targets: An experimental validation: Variations in visual acuity under different conditions of illumination,” , U. S. Naval Submarine Base, New London, Connecticut, December, 1948.
  8. Morris, Katz, and Bowen, J. Opt. Soc. Am. 45, 834–838 (1955).
    [Crossref] [PubMed]
  9. Badal, Ann. oculist 75, 5–13 (January–February, 1876).
  10. G. A. Fry, Am. J. Optometry. 30, 22–37 (January, 1953).
    [Crossref]
  11. M. Françon, Rev. opt. 30, 71–80 (1951).
  12. Ogle, Imus, Madigan, Bannon, and Wilson, A. M. A. Arch. Ophthalmol. 24, 1179–1189 (1940).
    [Crossref]
  13. G. W. Hartmann, J. Expertl. Psychol. 16, 383–392 (1933).
    [Crossref]
  14. P. W. Cobb, Am. J. Physiol. 36, 335–346 (February, 1915).
  15. Gerald Westheimer, J. Opt. Soc. Am. 47, 714–718 (1957).
    [Crossref] [PubMed]
  16. F. W. Campbell and J. G. Robson, Nature (London) 181, 362 (1958).
    [Crossref]

1958 (2)

Sukeyuki Oshima, Japan. J. Ophthalmol. 2, 63–72 (1958).

F. W. Campbell and J. G. Robson, Nature (London) 181, 362 (1958).
[Crossref]

1957 (1)

1955 (1)

1953 (1)

G. A. Fry, Am. J. Optometry. 30, 22–37 (January, 1953).
[Crossref]

1952 (1)

Gunnar von Bahr, Acta Ophthalmol. 30, 39–44 (1952).

1951 (1)

M. Françon, Rev. opt. 30, 71–80 (1951).

1940 (1)

Ogle, Imus, Madigan, Bannon, and Wilson, A. M. A. Arch. Ophthalmol. 24, 1179–1189 (1940).
[Crossref]

1939 (1)

J. Adamson and E. F. Fincham, Trans. Ophthalmol. Soc., United Kingdom 59, 163–179 (1939).

1933 (1)

G. W. Hartmann, J. Expertl. Psychol. 16, 383–392 (1933).
[Crossref]

1915 (1)

P. W. Cobb, Am. J. Physiol. 36, 335–346 (February, 1915).

1876 (1)

Badal, Ann. oculist 75, 5–13 (January–February, 1876).

Adamson, J.

J. Adamson and E. F. Fincham, Trans. Ophthalmol. Soc., United Kingdom 59, 163–179 (1939).

Badal,

Badal, Ann. oculist 75, 5–13 (January–February, 1876).

Bannon,

Ogle, Imus, Madigan, Bannon, and Wilson, A. M. A. Arch. Ophthalmol. 24, 1179–1189 (1940).
[Crossref]

Bowen,

Campbell, F. W.

F. W. Campbell and J. G. Robson, Nature (London) 181, 362 (1958).
[Crossref]

F. W. Campbell, “The depth of field of the human eye,” (Great Britain, March, 1954).

Cobb, P. W.

P. W. Cobb, Am. J. Physiol. 36, 335–346 (February, 1915).

Dimmick, F. L.

F. L. Dimmick and L. M. Rudolph, “Checkerboard visual acuity targets: An experimental validation: Variations in visual acuity under different conditions of illumination,” , U. S. Naval Submarine Base, New London, Connecticut, December, 1948.

Fincham, E. F.

J. Adamson and E. F. Fincham, Trans. Ophthalmol. Soc., United Kingdom 59, 163–179 (1939).

Françon, M.

M. Françon, Rev. opt. 30, 71–80 (1951).

Fry, G. A.

G. A. Fry, Am. J. Optometry. 30, 22–37 (January, 1953).
[Crossref]

Hartmann, G. W.

G. W. Hartmann, J. Expertl. Psychol. 16, 383–392 (1933).
[Crossref]

Imus,

Ogle, Imus, Madigan, Bannon, and Wilson, A. M. A. Arch. Ophthalmol. 24, 1179–1189 (1940).
[Crossref]

Katz,

Madigan,

Ogle, Imus, Madigan, Bannon, and Wilson, A. M. A. Arch. Ophthalmol. 24, 1179–1189 (1940).
[Crossref]

Morris,

Ogle,

Ogle, Imus, Madigan, Bannon, and Wilson, A. M. A. Arch. Ophthalmol. 24, 1179–1189 (1940).
[Crossref]

Ogle, K. N.

K. N. Ogle, “Measurements on the depth of focus of the human eye with various test objects,” (unpublished thesis, Dartmouth College, Hanover, New Hampshire, 1927).

Oshima, Sukeyuki

Sukeyuki Oshima, Japan. J. Ophthalmol. 2, 63–72 (1958).

Robson, J. G.

F. W. Campbell and J. G. Robson, Nature (London) 181, 362 (1958).
[Crossref]

Rudolph, L. M.

F. L. Dimmick and L. M. Rudolph, “Checkerboard visual acuity targets: An experimental validation: Variations in visual acuity under different conditions of illumination,” , U. S. Naval Submarine Base, New London, Connecticut, December, 1948.

von Bahr, Gunnar

Gunnar von Bahr, Acta Ophthalmol. 30, 39–44 (1952).

Westheimer, Gerald

Wilson,

Ogle, Imus, Madigan, Bannon, and Wilson, A. M. A. Arch. Ophthalmol. 24, 1179–1189 (1940).
[Crossref]

A. M. A. Arch. Ophthalmol. (1)

Ogle, Imus, Madigan, Bannon, and Wilson, A. M. A. Arch. Ophthalmol. 24, 1179–1189 (1940).
[Crossref]

Acta Ophthalmol. (1)

Gunnar von Bahr, Acta Ophthalmol. 30, 39–44 (1952).

Am. J. Optometry. (1)

G. A. Fry, Am. J. Optometry. 30, 22–37 (January, 1953).
[Crossref]

Am. J. Physiol. (1)

P. W. Cobb, Am. J. Physiol. 36, 335–346 (February, 1915).

Ann. oculist (1)

Badal, Ann. oculist 75, 5–13 (January–February, 1876).

J. Expertl. Psychol. (1)

G. W. Hartmann, J. Expertl. Psychol. 16, 383–392 (1933).
[Crossref]

J. Opt. Soc. Am. (2)

Japan. J. Ophthalmol. (1)

Sukeyuki Oshima, Japan. J. Ophthalmol. 2, 63–72 (1958).

Nature (London) (1)

F. W. Campbell and J. G. Robson, Nature (London) 181, 362 (1958).
[Crossref]

Rev. opt. (1)

M. Françon, Rev. opt. 30, 71–80 (1951).

Trans. Ophthalmol. Soc., United Kingdom (1)

J. Adamson and E. F. Fincham, Trans. Ophthalmol. Soc., United Kingdom 59, 163–179 (1939).

Other (4)

K. N. Ogle, “Measurements on the depth of focus of the human eye with various test objects,” (unpublished thesis, Dartmouth College, Hanover, New Hampshire, 1927).

F. W. Campbell, “The depth of field of the human eye,” (Great Britain, March, 1954).

“Adjutant General's Office, PRS report No. 742, studies in visual acuity, report of progress,” (Personnel Research Section, Washington, D. C., 1947).

F. L. Dimmick and L. M. Rudolph, “Checkerboard visual acuity targets: An experimental validation: Variations in visual acuity under different conditions of illumination,” , U. S. Naval Submarine Base, New London, Connecticut, December, 1948.

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 (7)

Fig. 1
Fig. 1

A perspective sketch of the instrument used to measure the depth of focus of the eye.

Fig. 2
Fig. 2

Typical data from one subject of proximal and distal limits of the depth of focus of the eye, plotted on a probability scale, and showing the deterioration of resolution with increased out-of-focus blurring.

Fig. 3
Fig. 3

Graph of the summary of the depth-of-focus measurements for one subject, for different angular sizes of the test target, for the 50% and estimated 99% levels of probable visual resolution.

Fig. 4
Fig. 4

Measurements of the depth of focus of the eye of one subject, for various entrance pupil sizes induced by the various drugs as indicated.

Fig. 5
Fig. 5

The same data as those of Fig. 4, but plotted with pupil size on a reciprocal scale.

Fig. 6
Fig. 6

The results for three subjects showing the change in the depth of focus of the eye at the 50% level of probable visual resolution with change in entrance pupil size induced by drugs. Each point is the mean of determinations on 3 separate days.

Fig. 7
Fig. 7

Graphic illustration of the hyperfocal distances computed for the three subjects on the basis of data from depth-of- focus measurements.

Tables (1)

Tables Icon

Table I Average depth-of-focus measurements of three observers.a

Equations (3)

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

T = 1 / p - 1 / d .
Q = F 2 u - F ,
1 / p - 1 / c = 1 / c - 1 / d = 1 2 T .