Abstract

In the earth observation domain, two classes of sensors may be distinguished: a class for which sensor performances are driven by radiometric accuracy of the images and a class for which sensor performances are driven by spatial resolution. In this latter case, as spatial resolution depends on the triplet constituted by the Ground Sampling Distance (GSD), Modulation Transfer Function (MTF), and Signal to Noise Ratio (SNR), refocusing, acting as an MTF improvement, is very important. Refocusing is not difficult by itself as far as the on-board mechanism is reliable. The difficulty is on the defocus assessment side. Some methods such as those used for the SPOT family rely on the ability of the satellite to image the same landscape with two focusing positions. This can be done with a bi-sensor configuration, with adequate focal plane, or with the satellite agility. A new generation of refocusing mechanism will be taken aboard Pleiades. As the speed of this mechanism will be much slower than the speed of the older generation, it won’t be possible, despite the agility of the satellite, to image the same landscape with two focusing positions on the same orbit. That’s why methods relying on MTF measurement with edge method have been studied. This paper describes the methods and the work done to assess the defocus measurement accuracy in the Pleiades context.

© 2010 OSA

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. M. R. B. Forshaw, A. Haskell, P. F. Miller, D. J. Stanley, and J. R. G. Townshend, “Spatial resolution of remotely sensed imagery - A review paper,” Int. J. Remote Sens. 4(3), 497–520 (1983).
    [CrossRef]
  2. D. Léger, F. Viallefont, and D. Hillairet, “In-flight refocusing and MTF assessment of SPOT5 HRG and HRS cameras,” Proc. SPIE 4881, 224–231 (2003).
    [CrossRef]
  3. W. H. Steel, “The defocused image of sinusoidal gratings,” Opt. Acta (Lond.) 3, 65–74 (1956).
  4. K. Maeda, M. Kojima, and Y. Azuma, “Geometric and radiometric performance evaluation methods for marine observation satellite-1 (MOS-1) verification program (MVP),” Acta Astronaut. 15(6-7), 297–304 (1987).
    [CrossRef]
  5. T. Choi, “IKONOS satellite in orbit, modulation transfer function measurement using edge and pulse methods”, MSc Thesis, South Dakota State University (2002).
  6. F. Lei and H. J. Tiziani, “A comparison of methods to measure the modulation transfer function of aerial survey lens systems from image structures,” Photogramm. Eng. Remote Sensing 54, 41–46 (1988).
  7. H. Hwang, Y.-W. Choi, S. Kwak, M. Kim, and W. Park, “MTF assessment of high resolution satellite images using ISO 12233 slanted-edge method,” Proc. SPIE 7109, 710905 (2008).
    [CrossRef]
  8. F. Viallefont-Robinet and D. Léger, “Improvement of the edge method for on-orbit MTF measurement,” Opt. Express 18(4Issue 4), 3531–3545 (2010), http://www.opticsinfobase.org/oe/abstract.cfm?uri=oe-18-4-3531 .
    [CrossRef] [PubMed]
  9. A. Rosak, C. Latry, V. Pascal, and D. Laubier, “From SPOT5 to Pleiades-HR: evolutions of the instrumental specifications,” in Proceedings of the 5th international conference on Space Optics, B. Warmbein, ed. (ESA SP-554, Noordwijk, Netherlands, 2004), 141–148.

2010 (1)

2008 (1)

H. Hwang, Y.-W. Choi, S. Kwak, M. Kim, and W. Park, “MTF assessment of high resolution satellite images using ISO 12233 slanted-edge method,” Proc. SPIE 7109, 710905 (2008).
[CrossRef]

2003 (1)

D. Léger, F. Viallefont, and D. Hillairet, “In-flight refocusing and MTF assessment of SPOT5 HRG and HRS cameras,” Proc. SPIE 4881, 224–231 (2003).
[CrossRef]

1988 (1)

F. Lei and H. J. Tiziani, “A comparison of methods to measure the modulation transfer function of aerial survey lens systems from image structures,” Photogramm. Eng. Remote Sensing 54, 41–46 (1988).

1987 (1)

K. Maeda, M. Kojima, and Y. Azuma, “Geometric and radiometric performance evaluation methods for marine observation satellite-1 (MOS-1) verification program (MVP),” Acta Astronaut. 15(6-7), 297–304 (1987).
[CrossRef]

1983 (1)

M. R. B. Forshaw, A. Haskell, P. F. Miller, D. J. Stanley, and J. R. G. Townshend, “Spatial resolution of remotely sensed imagery - A review paper,” Int. J. Remote Sens. 4(3), 497–520 (1983).
[CrossRef]

1956 (1)

W. H. Steel, “The defocused image of sinusoidal gratings,” Opt. Acta (Lond.) 3, 65–74 (1956).

Azuma, Y.

K. Maeda, M. Kojima, and Y. Azuma, “Geometric and radiometric performance evaluation methods for marine observation satellite-1 (MOS-1) verification program (MVP),” Acta Astronaut. 15(6-7), 297–304 (1987).
[CrossRef]

Choi, Y.-W.

H. Hwang, Y.-W. Choi, S. Kwak, M. Kim, and W. Park, “MTF assessment of high resolution satellite images using ISO 12233 slanted-edge method,” Proc. SPIE 7109, 710905 (2008).
[CrossRef]

Forshaw, M. R. B.

M. R. B. Forshaw, A. Haskell, P. F. Miller, D. J. Stanley, and J. R. G. Townshend, “Spatial resolution of remotely sensed imagery - A review paper,” Int. J. Remote Sens. 4(3), 497–520 (1983).
[CrossRef]

Haskell, A.

M. R. B. Forshaw, A. Haskell, P. F. Miller, D. J. Stanley, and J. R. G. Townshend, “Spatial resolution of remotely sensed imagery - A review paper,” Int. J. Remote Sens. 4(3), 497–520 (1983).
[CrossRef]

Hillairet, D.

D. Léger, F. Viallefont, and D. Hillairet, “In-flight refocusing and MTF assessment of SPOT5 HRG and HRS cameras,” Proc. SPIE 4881, 224–231 (2003).
[CrossRef]

Hwang, H.

H. Hwang, Y.-W. Choi, S. Kwak, M. Kim, and W. Park, “MTF assessment of high resolution satellite images using ISO 12233 slanted-edge method,” Proc. SPIE 7109, 710905 (2008).
[CrossRef]

Kim, M.

H. Hwang, Y.-W. Choi, S. Kwak, M. Kim, and W. Park, “MTF assessment of high resolution satellite images using ISO 12233 slanted-edge method,” Proc. SPIE 7109, 710905 (2008).
[CrossRef]

Kojima, M.

K. Maeda, M. Kojima, and Y. Azuma, “Geometric and radiometric performance evaluation methods for marine observation satellite-1 (MOS-1) verification program (MVP),” Acta Astronaut. 15(6-7), 297–304 (1987).
[CrossRef]

Kwak, S.

H. Hwang, Y.-W. Choi, S. Kwak, M. Kim, and W. Park, “MTF assessment of high resolution satellite images using ISO 12233 slanted-edge method,” Proc. SPIE 7109, 710905 (2008).
[CrossRef]

Léger, D.

Lei, F.

F. Lei and H. J. Tiziani, “A comparison of methods to measure the modulation transfer function of aerial survey lens systems from image structures,” Photogramm. Eng. Remote Sensing 54, 41–46 (1988).

Maeda, K.

K. Maeda, M. Kojima, and Y. Azuma, “Geometric and radiometric performance evaluation methods for marine observation satellite-1 (MOS-1) verification program (MVP),” Acta Astronaut. 15(6-7), 297–304 (1987).
[CrossRef]

Miller, P. F.

M. R. B. Forshaw, A. Haskell, P. F. Miller, D. J. Stanley, and J. R. G. Townshend, “Spatial resolution of remotely sensed imagery - A review paper,” Int. J. Remote Sens. 4(3), 497–520 (1983).
[CrossRef]

Park, W.

H. Hwang, Y.-W. Choi, S. Kwak, M. Kim, and W. Park, “MTF assessment of high resolution satellite images using ISO 12233 slanted-edge method,” Proc. SPIE 7109, 710905 (2008).
[CrossRef]

Stanley, D. J.

M. R. B. Forshaw, A. Haskell, P. F. Miller, D. J. Stanley, and J. R. G. Townshend, “Spatial resolution of remotely sensed imagery - A review paper,” Int. J. Remote Sens. 4(3), 497–520 (1983).
[CrossRef]

Steel, W. H.

W. H. Steel, “The defocused image of sinusoidal gratings,” Opt. Acta (Lond.) 3, 65–74 (1956).

Tiziani, H. J.

F. Lei and H. J. Tiziani, “A comparison of methods to measure the modulation transfer function of aerial survey lens systems from image structures,” Photogramm. Eng. Remote Sensing 54, 41–46 (1988).

Townshend, J. R. G.

M. R. B. Forshaw, A. Haskell, P. F. Miller, D. J. Stanley, and J. R. G. Townshend, “Spatial resolution of remotely sensed imagery - A review paper,” Int. J. Remote Sens. 4(3), 497–520 (1983).
[CrossRef]

Viallefont, F.

D. Léger, F. Viallefont, and D. Hillairet, “In-flight refocusing and MTF assessment of SPOT5 HRG and HRS cameras,” Proc. SPIE 4881, 224–231 (2003).
[CrossRef]

Viallefont-Robinet, F.

Acta Astronaut. (1)

K. Maeda, M. Kojima, and Y. Azuma, “Geometric and radiometric performance evaluation methods for marine observation satellite-1 (MOS-1) verification program (MVP),” Acta Astronaut. 15(6-7), 297–304 (1987).
[CrossRef]

Int. J. Remote Sens. (1)

M. R. B. Forshaw, A. Haskell, P. F. Miller, D. J. Stanley, and J. R. G. Townshend, “Spatial resolution of remotely sensed imagery - A review paper,” Int. J. Remote Sens. 4(3), 497–520 (1983).
[CrossRef]

Opt. Acta (Lond.) (1)

W. H. Steel, “The defocused image of sinusoidal gratings,” Opt. Acta (Lond.) 3, 65–74 (1956).

Opt. Express (1)

Photogramm. Eng. Remote Sensing (1)

F. Lei and H. J. Tiziani, “A comparison of methods to measure the modulation transfer function of aerial survey lens systems from image structures,” Photogramm. Eng. Remote Sensing 54, 41–46 (1988).

Proc. SPIE (2)

H. Hwang, Y.-W. Choi, S. Kwak, M. Kim, and W. Park, “MTF assessment of high resolution satellite images using ISO 12233 slanted-edge method,” Proc. SPIE 7109, 710905 (2008).
[CrossRef]

D. Léger, F. Viallefont, and D. Hillairet, “In-flight refocusing and MTF assessment of SPOT5 HRG and HRS cameras,” Proc. SPIE 4881, 224–231 (2003).
[CrossRef]

Other (2)

T. Choi, “IKONOS satellite in orbit, modulation transfer function measurement using edge and pulse methods”, MSc Thesis, South Dakota State University (2002).

A. Rosak, C. Latry, V. Pascal, and D. Laubier, “From SPOT5 to Pleiades-HR: evolutions of the instrumental specifications,” in Proceedings of the 5th international conference on Space Optics, B. Warmbein, ed. (ESA SP-554, Noordwijk, Netherlands, 2004), 141–148.

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

Salon-de-Provence checkerboard target.

Fig. 2
Fig. 2

MTF as function of refocusing mechanism position.

Fig. 3
Fig. 3

Values of defocus of each position.

Fig. 4
Fig. 4

Choice of fd frequency.

Fig. 5
Fig. 5

MTF(0.3fe,0,p) as a function of refocusing mechanism position.

Fig. 6
Fig. 6

Values of defocus of each position.

Fig. 7
Fig. 7

Error on defocus measurement as a function of factor C for various modalities of factor M.

Fig. 8
Fig. 8

Error on defocus measurement with fd = 0.3fe.

Tables (2)

Tables Icon

Table 1 Variance analysis

Tables Icon

Table 2 Error on defocus measurement

Equations (2)

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

H ( f x , f y , Δ ) = H 0 ( f x , f y , 0 ) × H d e f o c ( f x , f y , Δ )
H d e f o c ( f x , f y , Δ ) = 2 J 1 ( π Δ N ( f x 2 + f y 2 ) 1 / 2 [ 1 λ N ( f x 2 + f y 2 ) 1 / 2 ] ) π Δ N ( f x 2 + f y 2 ) 1 / 2 [ 1 λ N ( f x 2 + f y 2 ) 1 / 2 ]

Metrics