Abstract

MgF2-overcoated aluminum films with high-vacuum ultraviolet reflectance have been the subject of further investigations of the preparation parameters affecting their reflectance, and of the effect of aging and exposure to conditions likely to be encountered in their applications. Techniques for monitoring the thickness of MgF2 by reflectance measurements with ultraviolet light and by complete evaporation of weighed quantities of MgF2 are described. It is shown that MgF2-protected aluminum mirrors retain their high-vacuum ultraviolet reflectance during extended exposure to air, ultraviolet irradiation, and bombardment with 1-MeV electrons and 5-MeV protons, and that such mirrors can be easily cleaned if contaminated with oil.

© 1966 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. G. Hass, R. Tousey, J. Opt. Soc. Am. 49, 593 (1959).
    [CrossRef]
  2. P. H. Berning, G. Hass, R. P. Madden, J. Opt. Soc. Am. 50, 586 (1960).
    [CrossRef]
  3. R. P. Madden, L. R. Canfield, G. Hass, J. Opt. Soc. Am. 53, 620 (1963).
    [CrossRef]
  4. W. R. Hunter, J. Opt. Soc. Am. 54, 208 (1964).
    [CrossRef]
  5. R. P. Madden, L. R. Canfield, J. Opt. Soc. Am. 51, 838 (1961).
    [CrossRef]
  6. J. A. Berning, P. H. Berning, J. Opt. Soc. Am. 50, 813 (1960).
    [CrossRef]
  7. J. T. Cox, G. Hass, J. B. Ramsey, J. Phys. Radium 25, 250 (1964).
  8. D. Fabre, J. Romand, J. Phys. Radium 22, 324 (1961).
    [CrossRef]
  9. W. Walkenhorst, Z. Tech. Physik 22, 14 (1941).
  10. N. Cabrera, Phil. Mag. 40, 175 (1949).
  11. G. Hass, W. R. Hunter, R. Tousey, J. Opt. Soc. Am. 47, 1070 (1957).
    [CrossRef]

1964 (2)

W. R. Hunter, J. Opt. Soc. Am. 54, 208 (1964).
[CrossRef]

J. T. Cox, G. Hass, J. B. Ramsey, J. Phys. Radium 25, 250 (1964).

1963 (1)

1961 (2)

1960 (2)

1959 (1)

1957 (1)

1949 (1)

N. Cabrera, Phil. Mag. 40, 175 (1949).

1941 (1)

W. Walkenhorst, Z. Tech. Physik 22, 14 (1941).

Berning, J. A.

Berning, P. H.

Cabrera, N.

N. Cabrera, Phil. Mag. 40, 175 (1949).

Canfield, L. R.

Cox, J. T.

J. T. Cox, G. Hass, J. B. Ramsey, J. Phys. Radium 25, 250 (1964).

Fabre, D.

D. Fabre, J. Romand, J. Phys. Radium 22, 324 (1961).
[CrossRef]

Hass, G.

Hunter, W. R.

Madden, R. P.

Ramsey, J. B.

J. T. Cox, G. Hass, J. B. Ramsey, J. Phys. Radium 25, 250 (1964).

Romand, J.

D. Fabre, J. Romand, J. Phys. Radium 22, 324 (1961).
[CrossRef]

Tousey, R.

Walkenhorst, W.

W. Walkenhorst, Z. Tech. Physik 22, 14 (1941).

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 (9)

Fig. 1
Fig. 1

Monitoring curve for controlling MgF2-film thickness during the deposition by measuring the decrease in reflectance of a glass surface at λ = 2537 Å. (4% reflectance = 100 scale divisions.)

Fig. 2
Fig. 2

Calculated effect of oxide films of various thicknesses on the reflectance of Al at λ = 1216 Å and 1026 Å. (At λ = 1216 Å, Al: N = 0.0586 − 1.04i, Al2O3: N = 1.72 − 0.62i; at λ = 1026 Å, Al: N = 0.0524 − 0.709i, Al2O3: N = 1.56 − 0.805i.)

Fig. 3
Fig. 3

Reflectance of films of Al and of Al overcoated with 250 Å of MgF2 directly after their deposition and during exposure to air. λ = 1216 Å.

Fig. 4
Fig. 4

Reflectance of evaporated Al from 1000 Å to 2000 Å with and without protective layers of MgF2 of two different thicknesses.

Fig. 5
Fig. 5

Calculated effect of surface films with n = 1.6 and values of k ranging from 0 to 0.1 on the reflectance of Al at λ = 1216 Å.

Fig. 6
Fig. 6

Calculated effect of an interposed layer of Al2O3 on the reflectance of MgF2-overcoated Al at λ = 1216 Å as a function of Al2O3-film thickness.

Fig. 7
Fig. 7

Measured effect of a delay between Al and MgF2 depositions on the reflectance of MgF2-overcoated Al at λ = 1216 Å. (Pressure in the vacuum apparatus during the delay time 1 × 10−6 torr to 5 × 10−7 torr.)

Fig. 8
Fig. 8

Measured effect of uv irradiation on the 1216-Å reflectance of Al (24 h old) and of Al overcoated with 250 Å of MgF2.

Fig. 9
Fig. 9

Measured effect of uv irradiation on the 1216-Å reflectance of unprotected 1-day, 7-day, and 14-month old Al films.

Tables (1)

Tables Icon

Table I Reflectance of MgF2-Protected Aluminum Mirrors before and after Irradiation with 1-MeV Electrons and 5-MeV Protons

Metrics