Abstract

By means of a large aperture quartz spectroradiometer the spectral energy distribution of a special variable-length mercury lamp was measured between 14,000 A and 2300 A under widely varying conditions. The effects of current, voltage and ventilation on the radiation at fifteen important maxima were measured, including three maxima in the infrared, four in the visible, and eight in the ultraviolet. The composition of each maximum is given, and curves are plotted showing the degree of resolution used; the variation in intensity of each maximum with voltage gradient at constant current; the variation of intensity of the strong ultraviolet maximum near 3660 A with voltage for five current values from two to four amperes; the stationary characteristic curves of a high pressure arc; two typical cases of spectral energy distribution at constant power; and the variation with current of the intensity of each maximum at constant power.

It was found that for constant current the energy in each maximum except those in the infrared increased linearly with the voltage after a certain minimum (near 8 volts for 2.5 amperes) was reached. The pressure was measured for each stationary state used, the extreme values being 20 mm of mercury and two atmospheres. Where power input was constant the energy radiated in each maximum increased rapidly with decreasing current. It was found that the most satisfactory condition for running an arc at pressures under two atmospheres, at least, was to have the pressure as high as possible, so that for a given power input the voltage was high and the current low. This condition gives the greatest efficiency and the least change in energy distribution with total energy variation. The relation of pressure to the other variables and the effects at higher pressures are being investigated further; also an absolute determination is being made of the energy available in each wave-length for photochemical purposes.

© 1925 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. Küch and Retschinsky, Ann. der Phys.,  20, p. 563; 1906.
    [Crossref]
  2. Ibid,  22, p. 595; 1907.
  3. Ibid,  22, p. 852; 1907.
  4. Pflüger, Ann. der Phys.,  26, p. 789; 1908.
    [Crossref]
  5. Athanasiu, Compt. Rend.,  178, p. 2071; 1924.
  6. Ladenburg, Phys. Zeits.,  5, p. 524; 1904.
  7. Fabry and Buisson, Compt. Rend.,  153, p. 93; 1911.
  8. Winther, Z. Electrochem.,  20, p. 109; 1914.
  9. Souder, Phys. Rev.,  8, p. 683; 1916.
    [Crossref]
  10. Coblentz, Long, and Kahler, ; 1918.
  11. Coblentz and Kahler, Bur. Stds. Sci. Papers, 378, 233; 1920.
  12. Koppius, Phys. Rev.,  18, p. 443; 1921.
    [Crossref]
  13. Buttolph, Cooper-Hewitt Bull., 105.
  14. Buttolph, Gen. Elec. Rev.,  23, 741 and 858 and 909; 1920.

1924 (1)

Athanasiu, Compt. Rend.,  178, p. 2071; 1924.

1921 (1)

Koppius, Phys. Rev.,  18, p. 443; 1921.
[Crossref]

1920 (2)

Buttolph, Gen. Elec. Rev.,  23, 741 and 858 and 909; 1920.

Coblentz and Kahler, Bur. Stds. Sci. Papers, 378, 233; 1920.

1916 (1)

Souder, Phys. Rev.,  8, p. 683; 1916.
[Crossref]

1914 (1)

Winther, Z. Electrochem.,  20, p. 109; 1914.

1911 (1)

Fabry and Buisson, Compt. Rend.,  153, p. 93; 1911.

1908 (1)

Pflüger, Ann. der Phys.,  26, p. 789; 1908.
[Crossref]

1907 (2)

Ibid,  22, p. 595; 1907.

Ibid,  22, p. 852; 1907.

1906 (1)

Küch and Retschinsky, Ann. der Phys.,  20, p. 563; 1906.
[Crossref]

1904 (1)

Ladenburg, Phys. Zeits.,  5, p. 524; 1904.

Athanasiu,

Athanasiu, Compt. Rend.,  178, p. 2071; 1924.

Buisson,

Fabry and Buisson, Compt. Rend.,  153, p. 93; 1911.

Buttolph,

Buttolph, Gen. Elec. Rev.,  23, 741 and 858 and 909; 1920.

Buttolph, Cooper-Hewitt Bull., 105.

Coblentz,

Coblentz and Kahler, Bur. Stds. Sci. Papers, 378, 233; 1920.

Coblentz, Long, and Kahler, ; 1918.

Fabry,

Fabry and Buisson, Compt. Rend.,  153, p. 93; 1911.

Kahler,

Coblentz and Kahler, Bur. Stds. Sci. Papers, 378, 233; 1920.

Coblentz, Long, and Kahler, ; 1918.

Koppius,

Koppius, Phys. Rev.,  18, p. 443; 1921.
[Crossref]

Küch,

Küch and Retschinsky, Ann. der Phys.,  20, p. 563; 1906.
[Crossref]

Ladenburg,

Ladenburg, Phys. Zeits.,  5, p. 524; 1904.

Long,

Coblentz, Long, and Kahler, ; 1918.

Pflüger,

Pflüger, Ann. der Phys.,  26, p. 789; 1908.
[Crossref]

Retschinsky,

Küch and Retschinsky, Ann. der Phys.,  20, p. 563; 1906.
[Crossref]

Souder,

Souder, Phys. Rev.,  8, p. 683; 1916.
[Crossref]

Winther,

Winther, Z. Electrochem.,  20, p. 109; 1914.

Ann. der Phys. (2)

Küch and Retschinsky, Ann. der Phys.,  20, p. 563; 1906.
[Crossref]

Pflüger, Ann. der Phys.,  26, p. 789; 1908.
[Crossref]

Bur. Stds. Sci. Papers (1)

Coblentz and Kahler, Bur. Stds. Sci. Papers, 378, 233; 1920.

Compt. Rend. (2)

Athanasiu, Compt. Rend.,  178, p. 2071; 1924.

Fabry and Buisson, Compt. Rend.,  153, p. 93; 1911.

Cooper-Hewitt Bull. (1)

Buttolph, Cooper-Hewitt Bull., 105.

Gen. Elec. Rev. (1)

Buttolph, Gen. Elec. Rev.,  23, 741 and 858 and 909; 1920.

Ibid (2)

Ibid,  22, p. 595; 1907.

Ibid,  22, p. 852; 1907.

Phys. Rev. (2)

Souder, Phys. Rev.,  8, p. 683; 1916.
[Crossref]

Koppius, Phys. Rev.,  18, p. 443; 1921.
[Crossref]

Phys. Zeits. (1)

Ladenburg, Phys. Zeits.,  5, p. 524; 1904.

Z. Electrochem. (1)

Winther, Z. Electrochem.,  20, p. 109; 1914.

Other (1)

Coblentz, Long, and Kahler, ; 1918.

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)

F. 1
F. 1

Curves T1….T3 are stationary characteristic curves, applying only after the lamp has come to a steady state. To pass from one of these to another a change must be made in the ventilation of any lamp.

F. 2
F. 2

The special design of quartz mercury vapor lamp used in this work, arranged for variation of pressure, arc length, voltage gradient, current, series resistance, and rate of cooling.

F. 3
F. 3

The spectroradiometer used to measure the intensity distribution in the spectrum of the quartz mercury vapor lamp.

F. 4
F. 4

Two energy distribution curves taken for approximately the same power inputs, showing the maxima measured, the degree of resolution obtained, and the increase in intensity obtainable by using high voltages and small currents for a given power.

F. 5
F. 5

Curves showing the variation of energy with voltage gradient at constant current for ten of the most important maxima.

F. 6
F. 6

The dotted curves connect points for the same power input.

F. 7
F. 7

Curves showing the variation of energy in the most important maxima with current, at a constant power input of 25 watts per cm.

Tables (2)