Abstract

Remote pollutant measurement by absorption using topographical reflectors or atmospheric Mie scattering as a distributed reflector offers increased range and sensitivity compared to that achieved by Raman or resonance backscattering methods. The use of topographical reflectors offers the advantage of a single-ended absorption measurement for ranges up to 10 km and sensitivities to less than 0.01 ppm for a 10-mJ, 100-nsec transmitted pulse. The distributed Mie reflector permits absorption measurements over a depth /2, determined by the pulse length τ, and allows ranging by time-of-flight measurement. For a 100-mJ, 100-nsec pulse sensitivities to 0.3 ppm at a 15-m depth resolution to ranges of 1–4 km are possible. This sensitivity is 104 to 105 times better than that achieved by the Raman method.

© 1973 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. K. Kildal, R. L. Byer, Proc. IEEE 59, 1644 (1971).
    [CrossRef]
  2. Humio Inaba, Takao Kobayashi, Opto-Electronics 4, 101 (1972).
    [CrossRef]
  3. H. Inomata, T. Igarishi, Trans, Tech. Group Quantum Electron., Inst. Elec. Comm. Eng. (IECE) Japan, QE70-36, xxxx (1970) (in Japanese).
  4. E. Proctor (SRI, Menlo Park, Ca.); private communication.
  5. R. T. H. Collis, Appl. Opt. 9, 1782 (1970).
    [CrossRef] [PubMed]
  6. Recent work has indicated that a 1% absorption variation should be detectable in long-path atmospheric absorption measurements. L. Wright (SRI, Menlo Park, Ca.) private communication.
  7. P. W. Kruse, L. D. McGlauchlin, R. B. McQuistan, Elements of Infrared Technology (Wiley, New York, 1963).
  8. S. Twomey, H. B. Howell, Appl. Opt. 4, 501 (1965).
    [CrossRef]
  9. Robert W. Fenn, Appl. Opt. 5, 293 (1966).
    [CrossRef] [PubMed]
  10. K. Ya Kondratyev, Radiation in the Atmosphere (Academic Press, New York, 1969).
  11. William L. Wolfe, Ed., Handbook of Military Infrared Technology (Office of Naval Research, Washington, D.C., 1965).
  12. Thomas H. Maugh, Science 177, 338 (1972).
    [CrossRef] [PubMed]
  13. Raymond M. Measures, Gilles Pilon, Opto-Electronics 4, 141 (1972).
    [CrossRef]

1972 (3)

Humio Inaba, Takao Kobayashi, Opto-Electronics 4, 101 (1972).
[CrossRef]

Thomas H. Maugh, Science 177, 338 (1972).
[CrossRef] [PubMed]

Raymond M. Measures, Gilles Pilon, Opto-Electronics 4, 141 (1972).
[CrossRef]

1971 (1)

K. Kildal, R. L. Byer, Proc. IEEE 59, 1644 (1971).
[CrossRef]

1970 (2)

H. Inomata, T. Igarishi, Trans, Tech. Group Quantum Electron., Inst. Elec. Comm. Eng. (IECE) Japan, QE70-36, xxxx (1970) (in Japanese).

R. T. H. Collis, Appl. Opt. 9, 1782 (1970).
[CrossRef] [PubMed]

1966 (1)

1965 (1)

Byer, R. L.

K. Kildal, R. L. Byer, Proc. IEEE 59, 1644 (1971).
[CrossRef]

Collis, R. T. H.

Fenn, Robert W.

Howell, H. B.

Igarishi, T.

H. Inomata, T. Igarishi, Trans, Tech. Group Quantum Electron., Inst. Elec. Comm. Eng. (IECE) Japan, QE70-36, xxxx (1970) (in Japanese).

Inaba, Humio

Humio Inaba, Takao Kobayashi, Opto-Electronics 4, 101 (1972).
[CrossRef]

Inomata, H.

H. Inomata, T. Igarishi, Trans, Tech. Group Quantum Electron., Inst. Elec. Comm. Eng. (IECE) Japan, QE70-36, xxxx (1970) (in Japanese).

Kildal, K.

K. Kildal, R. L. Byer, Proc. IEEE 59, 1644 (1971).
[CrossRef]

Kobayashi, Takao

Humio Inaba, Takao Kobayashi, Opto-Electronics 4, 101 (1972).
[CrossRef]

Kruse, P. W.

P. W. Kruse, L. D. McGlauchlin, R. B. McQuistan, Elements of Infrared Technology (Wiley, New York, 1963).

Maugh, Thomas H.

Thomas H. Maugh, Science 177, 338 (1972).
[CrossRef] [PubMed]

McGlauchlin, L. D.

P. W. Kruse, L. D. McGlauchlin, R. B. McQuistan, Elements of Infrared Technology (Wiley, New York, 1963).

McQuistan, R. B.

P. W. Kruse, L. D. McGlauchlin, R. B. McQuistan, Elements of Infrared Technology (Wiley, New York, 1963).

Measures, Raymond M.

Raymond M. Measures, Gilles Pilon, Opto-Electronics 4, 141 (1972).
[CrossRef]

Pilon, Gilles

Raymond M. Measures, Gilles Pilon, Opto-Electronics 4, 141 (1972).
[CrossRef]

Proctor, E.

E. Proctor (SRI, Menlo Park, Ca.); private communication.

Twomey, S.

Wright, L.

Recent work has indicated that a 1% absorption variation should be detectable in long-path atmospheric absorption measurements. L. Wright (SRI, Menlo Park, Ca.) private communication.

Ya Kondratyev, K.

K. Ya Kondratyev, Radiation in the Atmosphere (Academic Press, New York, 1969).

Appl. Opt. (3)

Inst. Elec. Comm. Eng. (IECE) Japan (1)

H. Inomata, T. Igarishi, Trans, Tech. Group Quantum Electron., Inst. Elec. Comm. Eng. (IECE) Japan, QE70-36, xxxx (1970) (in Japanese).

Opto-Electronics (2)

Humio Inaba, Takao Kobayashi, Opto-Electronics 4, 101 (1972).
[CrossRef]

Raymond M. Measures, Gilles Pilon, Opto-Electronics 4, 141 (1972).
[CrossRef]

Proc. IEEE (1)

K. Kildal, R. L. Byer, Proc. IEEE 59, 1644 (1971).
[CrossRef]

Science (1)

Thomas H. Maugh, Science 177, 338 (1972).
[CrossRef] [PubMed]

Other (5)

Recent work has indicated that a 1% absorption variation should be detectable in long-path atmospheric absorption measurements. L. Wright (SRI, Menlo Park, Ca.) private communication.

P. W. Kruse, L. D. McGlauchlin, R. B. McQuistan, Elements of Infrared Technology (Wiley, New York, 1963).

E. Proctor (SRI, Menlo Park, Ca.); private communication.

K. Ya Kondratyev, Radiation in the Atmosphere (Academic Press, New York, 1969).

William L. Wolfe, Ed., Handbook of Military Infrared Technology (Office of Naval Research, Washington, D.C., 1965).

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 (8)

Fig. 1
Fig. 1

Schematic of the Mie backscatter absorption method showing the sampled depth for a given transmitted pulse length.

Fig. 2
Fig. 2

Reflected power vs range for detection of CO by backscattering from a distributed Mie reflector when tuned on and off the absorption line. Also shown is the derived pollutant concentration equal to the range derivative of ln(Proff/Pron).

Fig. 3
Fig. 3

Required transmitted energy vs range for CO detection at 4.7 μ. σmax indicates tuning on line center and σmin indicates tuning for minimum required energy.

Fig. 4
Fig. 4

Required transmitted energy vs range for NO2 detection at 0.40 μ for 5-km and 10-km visibilities. The NO2 is assumed to be uniformly distributed at a 0.1 ppm concentration.

Fig. 5
Fig. 5

Required transmitted energy vs range for CO detection at 4.7 μ for detection by backscattering from a distributed Mie reflector. For a 100-nsee pulse the depth resolution is 15 m and the minimum measurable pollutant concentration is 0.14 ppm.

Fig. 6
Fig. 6

Required transmitted energy vs range for NO2 detection at 0.40 μ by backscattering from a distributed Mie reflector. The minimum measurable NO2 concentration is 0.8 ppm.

Fig. 7
Fig. 7

S/N and measurement accuracy δ vs range for a topographical reflector assuming a 100-mJ, 100-nsec transmitted pulse.

Fig. 8
Fig. 8

S/N and measurement accuracy δ vs rarge for a distributed Mie reflector assuming a 100-mJ, 100-nsec transmitted pulse. The depth resolution is 15 m.

Tables (2)

Tables Icon

Table I Minimum Measurable Concentration for an Absorption Length of 100 M

Tables Icon

Table II Rayleigh and Mie Scattering Coefficients

Equations (47)

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

P r ( R ) = K ( c τ 2 ) β ( R ) A R 2 P 0 exp [ - 2 0 R α A ( r ) d r ] ,
P r ( R ) = K ρ A π R 2 P 0 exp [ - 2 0 R α A ( r ) d r ] ,
P r off = ( K ρ A P 0 / π R 2 ) exp ( - 2 α s c R ) ,
α s c = α Mie + α Ray .
P r on = ( K ρ A P 0 / π R 2 ) exp { - 2 R [ α s c + N A σ ( λ ) ] } exp [ - 2 σ 0 L N P ( L ) d L ] = P r off exp [ - 2 ( N A R + N P L ) σ ( λ ) ] ,
P r off - P r on = P r off { [ 1 - exp [ - 2 ( N A R + N B L ) σ ( λ ) ] }
Δ P r normal = P r off { 1 - exp [ - 2 N A R σ ( λ ) ] } ,
P r off exp [ - 2 N A R σ ( λ ) ] { 1 - exp [ - 2 N P L σ ( λ ) ] } = P N .
P r on = P r off exp [ - 2 N A R σ ( λ ) ] ,
P 0 = P N ( π / K ρ A ) R 2 ( exp { 2 [ α s c + N A σ ( λ ) ] R } / { 1 - exp [ - 2 N P L σ ( λ ) ] } ) ,
S / N = P r / ( 4 P r ( h ν / η ) Δ f + 2 N E P 2 Δ f ) 1 / 2 ,
P N = 4 ( h ν / η ) F Δ f ,
E 0 = P 0 τ = 4 ( h ν / η ) ( F / K ρ A ) R 2 ( exp { 2 [ α s c + N A σ ( λ ) ] R } / { 1 - exp [ - 2 N P L σ ( λ ) ] } ) ,
P N = N E P ( 2 Δ f ) 1 / 2
E 0 = P 0 τ = ( 2 π N E P τ / K ρ A ) R 2 ( exp { 2 [ α s c + N A σ ( λ ) ] R } / { 1 - exp [ - 2 N P L σ ( λ ) ] } ) ,
σ min = ln ( 1 + q ) / 2 N P L ,
σ min = 1 / 2 N A R ,             N P L N A R
E 0 = ( 2 π N E P τ / K ρ A ) · R 2 e 2 α s c R ( 1 + q ) 1 / q ( 1 + 1 / q )
x = 2 N P L σ ( λ ) = [ ln ( P r off / P r on ) - 2 N A R σ ( λ ) ] ,
( Δ x ) 2 = ( Δ P r / P r ) off 2 + ( Δ P r / P r ) on 2 .
( S / N ) 2 = ( x / Δ x ) 2 = { [ 2 N P L σ ( λ ) P r off ] 2 / 2 Δ f } / ( P r off ( h ν / η ) { 1 + exp [ 2 σ ( λ ) ( N P L + N A R ) ] } + N E P 2 { 1 + exp [ 4 σ ( λ ) ( N P L + N A R ) ] } ) .
σ opt = 2.22 / 2 ( N P L + N A R )             ( shot - noise limit )
σ opt = 1.11 / 2 ( N P L + N A R )             ( dark current or background limit ) .
S / N = x ( P r off / P N ) 1 / 2             ( shot - noise limit )
S / N = x ( P r off / P N )     ( dark current limit )
S / N = ( P r off / P N ) 1 / 2 ( shot - noise limit )
S / N = 0.33 ( P r off / P N ) ( dark current limit ) ,
η [ ( 0.37 × 10 - 27 ) / σ abs L ] ( m 3 ) .
α λ Mie = ( 3.91 / V ) ( 0.55 / λ ) 0.585 V + 1 / 3 km - 1 ,
E 0 1.19 × 10 - 3 R 2 ( exp { 2 [ α s c + N A σ ( λ ) ] R } / 1 - exp [ - 2 N P L σ ( λ ) ]     ( mJ ) .
E 0 > 1.19 × 10 - 3 R 2 exp ( 2 α s c R ) ( 1 + q ) 1 / q ( 1 + 1 / q ) ,
E 0 = [ 1.25 × 10 - 5 R 2 exp ( 2 α s c R ) ] / { 1 - exp [ 2 N P L σ ( λ ) ] } ,
β ( R ) Mie
β ( R ) Mie = a λ Mie · ζ ,
β Ray ( r ) = ( 3 / 16 π ) a λ Ray .
β ( R ) = β ( R ) Mie + β ( R ) Ray .
E 0 = [ 4 N E P / c β ( R ) K A ] ( 1 τ ) R 2 ( exp { 2 [ α s c + N A σ ( λ ) ] R } / { 1 - exp [ - 2 N P L σ ( λ ) ] } ) .
α Mie = 1 / 2 R .
E 0 = 1.8 R 2 ( exp { 2 [ α s c + N A σ ( λ ) ] R } / { 1 - exp [ - 2 N P L σ ( λ ) ] } ) ( mJ ) ,
E 0 = 18 R 2 exp ( 2 α s c R )     ( mJ ) .
E 0 = ( 8 / π ) ( F / K A ) ( h ν / η ) [ 1 / c τ β ( R ) ] R 2 ( exp { 2 [ α s c + N A σ ( λ ) ] R } / { 1 - exp [ - 2 N P L σ ( λ ) ] } ) .
E 0 = 3.7 × 10 - 4 R 2 ( exp { 2 [ α s c + N A σ ( λ ) ] R } / { 1 - exp [ - 2 N P L σ ( λ ) ] } )
E 0 = 6.7 × 10 - 4 R 2 ( exp { 2 [ α s c + N A σ ( λ ) ] R } / { 1 - exp [ - 2 N P L σ ( λ ) ] } )
S / N = x [ E T / E 0 ( R ) ] 1 / 2             x 1 ,
= [ E T / E 0 ( R ) ] 1 / 2             σ = σ opt ,
S / N = E T / E 0 ( R )             x 1 ,
= 0.4 E T / E 0 ( R )             σ = σ opt ,

Metrics