Abstract

An approach to improving power densities on target for high-energy laser systems operating in thermal blooming environments is presented. The concept employs small discrete subapertures in place of a large single aperture to reduce thermal blooming effects in the target region. Preliminary calculations indicate that subunit phase control is not essential to achieving adequate performance. Wave-optics computer codes were used to study key performance parameters in addition to predicting target irradiances for several simple (two- and four-subaperture) system models. Improvements of the order of 30% in peak irradiances were found, compared with equal total area single apertures. A preliminary evaluation implies that a multiaperture system can be configured to achieve at least comparable performance as a monolithic system but with smaller less costly optical elements.

© 1983 Optical Society of America

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References

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  1. F. G. Gebhart, Appl. Opt. 15, 1479 (1976).
    [CrossRef]
  2. D. C. Smith, Proc. IEEE 65, 1679 (1977).
    [CrossRef]
  3. R. H. Freeman, J. E. Pearson, Appl. Opt. 21, 580 (1982).
    [CrossRef] [PubMed]
  4. L. D. Barr, J. Opt. Soc. Am. 68, 1380 (1978).
  5. C. Yeh, J. E. Pearson, W. P. Brown, Appl. Opt. 15, 2913 (1976).
    [CrossRef] [PubMed]
  6. J. E. Pearson, C. Yeh, W. P. Brown, J. Opt. Soc. Am. 66, 1384 (1976).
    [CrossRef]
  7. C. Newman, D. C. Smith, Appl. Phys. Lett. 38, 590 (1981).
    [CrossRef]
  8. P. B. Ulrich, J. Opt. Soc. Am. 64, 549 (1974).
  9. D. R. Fields, Air Force Weapons Laboratory Report AFWL-TR-79-188 (July1980).
  10. K. G. Whitney, G. L. Mader, P. B. Ulrich, Naval Research Laboratory Report NRL-8074 (Feb.1977).
  11. L. C. Bradley, J. Herrmann, Appl. Opt. 13, 331 (1974).
    [CrossRef] [PubMed]
  12. A. B. Meinel, J. Opt. Soc. Am. 72, 14 (1982).
    [CrossRef]

1982

1981

C. Newman, D. C. Smith, Appl. Phys. Lett. 38, 590 (1981).
[CrossRef]

1978

L. D. Barr, J. Opt. Soc. Am. 68, 1380 (1978).

1977

D. C. Smith, Proc. IEEE 65, 1679 (1977).
[CrossRef]

1976

1974

Barr, L. D.

L. D. Barr, J. Opt. Soc. Am. 68, 1380 (1978).

Bradley, L. C.

Brown, W. P.

Fields, D. R.

D. R. Fields, Air Force Weapons Laboratory Report AFWL-TR-79-188 (July1980).

Freeman, R. H.

Gebhart, F. G.

Herrmann, J.

Mader, G. L.

K. G. Whitney, G. L. Mader, P. B. Ulrich, Naval Research Laboratory Report NRL-8074 (Feb.1977).

Meinel, A. B.

Newman, C.

C. Newman, D. C. Smith, Appl. Phys. Lett. 38, 590 (1981).
[CrossRef]

Pearson, J. E.

Smith, D. C.

C. Newman, D. C. Smith, Appl. Phys. Lett. 38, 590 (1981).
[CrossRef]

D. C. Smith, Proc. IEEE 65, 1679 (1977).
[CrossRef]

Ulrich, P. B.

P. B. Ulrich, J. Opt. Soc. Am. 64, 549 (1974).

K. G. Whitney, G. L. Mader, P. B. Ulrich, Naval Research Laboratory Report NRL-8074 (Feb.1977).

Whitney, K. G.

K. G. Whitney, G. L. Mader, P. B. Ulrich, Naval Research Laboratory Report NRL-8074 (Feb.1977).

Yeh, C.

Appl. Opt.

Appl. Phys. Lett.

C. Newman, D. C. Smith, Appl. Phys. Lett. 38, 590 (1981).
[CrossRef]

J. Opt. Soc. Am.

P. B. Ulrich, J. Opt. Soc. Am. 64, 549 (1974).

J. E. Pearson, C. Yeh, W. P. Brown, J. Opt. Soc. Am. 66, 1384 (1976).
[CrossRef]

A. B. Meinel, J. Opt. Soc. Am. 72, 14 (1982).
[CrossRef]

L. D. Barr, J. Opt. Soc. Am. 68, 1380 (1978).

Proc. IEEE

D. C. Smith, Proc. IEEE 65, 1679 (1977).
[CrossRef]

Other

D. R. Fields, Air Force Weapons Laboratory Report AFWL-TR-79-188 (July1980).

K. G. Whitney, G. L. Mader, P. B. Ulrich, Naval Research Laboratory Report NRL-8074 (Feb.1977).

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Figures (7)

Fig. 1
Fig. 1

Schematic of a four-subaperture system.

Fig. 2
Fig. 2

Peak irradiances delivered by single apertures as a function of aperture radius for three different power levels with turbulence, jitter, and blooming present.

Fig. 3
Fig. 3

(a) Relative peak irradiance Irel (as compared with diffraction-limited) as a function of absorption with no turbulence or jitter. The points are the AP code results as compared to an empirical curve determined by Smith.2 (b) Critical power curve for a single 80-cm aperture with no turbulence or jitter.

Fig. 4
Fig. 4

Comparison of dual-aperture results and single-aperture reference irradiances. The phase and orientation for each case are pictured below each bar on the chart.

Fig. 5
Fig. 5

Improvement in peak irradiance as a function of aperture separation for a dual-aperture system.

Fig. 6
Fig. 6

Effects of defocusing on peak irradiances for a single aperture with 30-cm radius. The focal factor is the change in focal distance (the target plane remains at 4 km).

Fig. 7
Fig. 7

Relative performance of a two- and four-subunit MAC system.

Tables (1)

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Table I Parameters Used in Computer Calculations Using ssparama Code

Equations (3)

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I I 0 = A 2 λ 2 F 2 ,
N = N c ( a i a f ) = μ t I 0 α Z 2 μ ρ C p υ a i ( a i a f ) ,
I rel = 1 1 + 0.1 N 1.2 exp ( α Z )

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