Abstract

This paper describes a submersible spectroradiometer for measuring the spectral distribution of the multiply scattered natural light in ocean or lake water. Because of the anticipated large range of flux levels in the spectrum at the exit slit, strong measures have been taken to reduce stray light within the instrument. These methods are described in some detail. Procedures for spectral alignment and calibration, determination of bandwidth, absolute calibration, and over-all testing of the instrument are described in detail and the probable errors introduced by various components are estimated. It is estimated that the precision of measurements, limited by random errors of data taking, will be within ±2.5% and that the absolute accuracy is between 5% and 12%. The major limitations on the accuracy are the uncertainties of the standard of spectral emittance and the measurement of the bandwidth of the instrument.

The instrument makes possible a mode II determination of the optical properties of natural water as a function of wavelength and can furnish data on the spectral distribution of the flux available for photosynthesis and animal stimulation.

© 1966 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. H. Ebert, Wied. Ann 38, 489 (1889).
    [Crossref]
  2. W. G. Fastie, J. Opt. Soc. Am. 42, 641 (1952).
    [Crossref]
  3. F. S. Johnson, J. Meteorol. 11, 431 (1954).
    [Crossref]
  4. E. O. Hulburt, J. Opt. Soc. Am. 35, 698 (1945).
    [Crossref] [PubMed]
  5. A. C. Hardy, J. Opt. Soc. Am. 25, 305 (1935).
    [Crossref]
  6. Developed by George Tate and Richard Johnson at this laboratory for field checking and as a reference level for photometric instruments.
  7. R. Stair, W. E. Schneider, and J. K. Jackson, Appl. Opt. 2, 1151 (1963).
    [Crossref]
  8. R. W. Preisendorfer and Union Géodésique et Géophysique Internationale, International Association of Physical Oceanography; Symposium on Radiant Energy in the Sea, Monographie No. 10, p. 11 (1961).
  9. J. E. Tyler, Bull. Scripps Inst. Oceanog. 7, 363 (1960).
  10. J. E. Tyler, Appl. Opt. 3, 105 (1964).
    [Crossref]

1964 (1)

1963 (1)

1961 (1)

R. W. Preisendorfer and Union Géodésique et Géophysique Internationale, International Association of Physical Oceanography; Symposium on Radiant Energy in the Sea, Monographie No. 10, p. 11 (1961).

1960 (1)

J. E. Tyler, Bull. Scripps Inst. Oceanog. 7, 363 (1960).

1954 (1)

F. S. Johnson, J. Meteorol. 11, 431 (1954).
[Crossref]

1952 (1)

1945 (1)

1935 (1)

1889 (1)

H. Ebert, Wied. Ann 38, 489 (1889).
[Crossref]

Ebert, H.

H. Ebert, Wied. Ann 38, 489 (1889).
[Crossref]

Fastie, W. G.

Hardy, A. C.

Hulburt, E. O.

Jackson, J. K.

Johnson, F. S.

F. S. Johnson, J. Meteorol. 11, 431 (1954).
[Crossref]

Preisendorfer, R. W.

R. W. Preisendorfer and Union Géodésique et Géophysique Internationale, International Association of Physical Oceanography; Symposium on Radiant Energy in the Sea, Monographie No. 10, p. 11 (1961).

Schneider, W. E.

Stair, R.

Tyler, J. E.

J. E. Tyler, Appl. Opt. 3, 105 (1964).
[Crossref]

J. E. Tyler, Bull. Scripps Inst. Oceanog. 7, 363 (1960).

Appl. Opt. (2)

Bull. Scripps Inst. Oceanog. (1)

J. E. Tyler, Bull. Scripps Inst. Oceanog. 7, 363 (1960).

J. Meteorol. (1)

F. S. Johnson, J. Meteorol. 11, 431 (1954).
[Crossref]

J. Opt. Soc. Am. (3)

Symposium on Radiant Energy in the Sea (1)

R. W. Preisendorfer and Union Géodésique et Géophysique Internationale, International Association of Physical Oceanography; Symposium on Radiant Energy in the Sea, Monographie No. 10, p. 11 (1961).

Wied. Ann (1)

H. Ebert, Wied. Ann 38, 489 (1889).
[Crossref]

Other (1)

Developed by George Tate and Richard Johnson at this laboratory for field checking and as a reference level for photometric instruments.

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 (6)

Fig. 1
Fig. 1

Diagram of the optical system of the Scripps Spectroradiometer. The rotating sector mirror is indicated at m.

Fig. 2
Fig. 2

Recorder response as a function of wavelength when the input flux to the Scripps spectroradiometer was centered at 550 nm and had a bandwidth at half the peak value of about 18 nm.

Fig. 3
Fig. 3

Arrangement of Hardy monochromator and Scripps spectroradiometer for obtaining wavelength and bandwidth calibration.

Fig. 4
Fig. 4

Typical recordings of bandwidth showing extrapolation lines. This figure has been traced from the data for purposes of reproduction.

Fig. 5
Fig. 5

Bandwidth of the Scripps spectroradiometer as a function of wavelength. Curve is best visual fit to the data points.

Fig. 6
Fig. 6

Diagram of mode II specification of the optical properties of ocean water. h and H are, respectively, the scalar and horizontal irradiance and are shown for the upwelling (+) and down-welling (−) flux fields. The property, a, is the absorption coefficient. (See Preisendorfer8 for further details).