Abstract

A novel, to our knowledge, scheme for a parallel joint transform correlator system is demonstrated by the introduction of a five-channel zone-plate image multiplicator combined with photographic referencing and is applied to the recognition of Devanagari script. For considering the script’s specific features, a partial image was obtained by means of windowing with 25 × 25 pixels out of a 64 × 64 pixel image of full-size characters and was employed for correlation. A comprehensive measurement of all 38 fundamental characters, namely, 1444 correlation pairs, showed satisfactory discrimination performance.

© 1998 Optical Society of America

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  1. Y. Ichioka, T. Iwaki, K. Matsuoka, “Optical information processing and beyond,” Proc. IEEE 84, 694–719 (1996).
    [CrossRef]
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    [CrossRef]
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    [CrossRef] [PubMed]
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    [CrossRef] [PubMed]
  8. J. L. Horner, “Single SLM joint transform correlator,” U.S. patent5,040,140 (13August1991).
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    [CrossRef]
  10. G. Lu, F. T. S. Yu, “Performance of phase-transformed input joint transform correlators,” Appl. Opt. 35, 304–312 (1996).
    [CrossRef] [PubMed]
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    [CrossRef]
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    [CrossRef] [PubMed]
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    [CrossRef]
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    [CrossRef]
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    [CrossRef]
  22. R. Thapliya, “Optical processing applied to recognition of Devanagari script,” Master’s thesis (University of Tokyo, Tokyo, Japan, March1996), Chap. 3.
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    [CrossRef]
  24. A. VanderLugt, Optical Signal Processing (Wiley, New York, 1992), Chap. 3.

1996 (6)

Y. Ichioka, T. Iwaki, K. Matsuoka, “Optical information processing and beyond,” Proc. IEEE 84, 694–719 (1996).
[CrossRef]

F. T. S. Yu, D. A. Gregory, “Optical pattern recognition: architectures and techniques,” Proc. IEEE 84, 733–752 (1996).
[CrossRef]

R. K. Wang, L. Shang, C. R. Chatwin, “Modified fringe-adjusted joint transform correlation to accommodate noise in the input scene,” Appl. Opt. 35, 286–295 (1996).
[CrossRef] [PubMed]

G. Lu, F. T. S. Yu, “Performance of phase-transformed input joint transform correlators,” Appl. Opt. 35, 304–312 (1996).
[CrossRef] [PubMed]

K. Keeni, H. Shimodaira, T. Nishino, S. Makino, Y. Tan, “Recognition of Devanagari characters using neural network,” IEICE Trans. Inf. Sys. E79-D, 523–528 (1996).

R. Thapliya, M. Tsuchiya, T. Kamiya, “Joint transform correlator applied to recognition of Devanagari script,” Opt. Rev. 3, 397–399 (1996).
[CrossRef]

1994 (3)

K. Kodate, E. Tokunaga, Y. Tatuno, J. Chen, T. Kamiya, “Efficient zone plate array accessor for optoelectronic integrated circuits: design and fabrication,” Appl. Opt. 29, 5115–5119 (1994).
[CrossRef]

J. Li, Y. Wang, J. Hu, “Experimental investigation of real-time nonlinear joint transform correlator,” Opt. Eng. 33, 3302–3305 (1994).
[CrossRef]

C. J. Kuo, “Joint transform correlator improved by means of a frequency-selective technique,” Opt. Eng. 33, 522–527 (1994).
[CrossRef]

1993 (1)

Q. Zhan, T. Minemoto, “Successful pattern matching with a large number of reference patterns using a joint transform correlator,” Jpn. J. Appl. Phys. 32, 3471–3476 (1993).
[CrossRef]

1991 (2)

1989 (1)

1982 (1)

1979 (1)

R. M. K. Singh, H. N. Mahabala, “Machine recognition of Devanagari script,” IEEE Trans. Sys. Man Cybern. SMC-9, 435–441 (1979).

1964 (1)

A. VanderLugt, “Signal detection by complex spatial filtering,” IEEE Trans. Inf. Theory IT-10, 139–145 (1964).

Arsenault, H. H.

Chatwin, C. R.

Chen, J.

Goodman, J. W.

J. W. Goodman, Introduction to Fourier Optics, 2nd ed. (McGraw-Hill, New York, 1996), Chap. 8.

Gregory, D. A.

F. T. S. Yu, D. A. Gregory, “Optical pattern recognition: architectures and techniques,” Proc. IEEE 84, 733–752 (1996).
[CrossRef]

Hashimoto, A.

K. Kodate, A. Hashimoto, Y. Takahashi, R. Thapliya, T. Kamiya, “Parallel facial recognition system based on optical joint transform correlator,” in Conference on Lasers and Electro-Optics CLEO/Pacific Rim ’97, Technical Digest (Institute of Electrical and Electronics Engineers, New York, 1997), paper FK3, pp. 276–277.
[CrossRef]

R. Thapliya, A. Hashimoto, K. Kodate, M. Tsuchiya, T. Kamiya, “Parallel optical processing applied to character recognition,” in Conference on Lasers and Electro-Optics CLEO/Pacific Rim ’97, Technical Digest (Institute of Electrical and Electronics Engineers, New York, 1997), paper FW4, pp. 310–311. (Part of this study was reported orally.)
[CrossRef]

Horner, J. L.

J. L. Horner, “Single SLM joint transform correlator,” U.S. patent5,040,140 (13August1991).

Hsu, Y. N.

Hu, J.

J. Li, Y. Wang, J. Hu, “Experimental investigation of real-time nonlinear joint transform correlator,” Opt. Eng. 33, 3302–3305 (1994).
[CrossRef]

Ichioka, Y.

Y. Ichioka, T. Iwaki, K. Matsuoka, “Optical information processing and beyond,” Proc. IEEE 84, 694–719 (1996).
[CrossRef]

Iwaki, T.

Y. Ichioka, T. Iwaki, K. Matsuoka, “Optical information processing and beyond,” Proc. IEEE 84, 694–719 (1996).
[CrossRef]

Javidi, B.

Kamiya, T.

R. Thapliya, M. Tsuchiya, T. Kamiya, “Joint transform correlator applied to recognition of Devanagari script,” Opt. Rev. 3, 397–399 (1996).
[CrossRef]

K. Kodate, E. Tokunaga, Y. Tatuno, J. Chen, T. Kamiya, “Efficient zone plate array accessor for optoelectronic integrated circuits: design and fabrication,” Appl. Opt. 29, 5115–5119 (1994).
[CrossRef]

R. Thapliya, A. Hashimoto, K. Kodate, M. Tsuchiya, T. Kamiya, “Parallel optical processing applied to character recognition,” in Conference on Lasers and Electro-Optics CLEO/Pacific Rim ’97, Technical Digest (Institute of Electrical and Electronics Engineers, New York, 1997), paper FW4, pp. 310–311. (Part of this study was reported orally.)
[CrossRef]

R. Thapliya, K. Kodate, M. Tsuchiya, T. Kamiya, “Character recognition of Sanskrit scripts using joint transform correlator,” in 1996 International Topical Meetings on Optical Computing, Technical Digest (Japan Society of Applied Physics, Tokyo, 1996), Vol. 1, paper OThB4, pp. 246–247.

K. Kodate, A. Hashimoto, Y. Takahashi, R. Thapliya, T. Kamiya, “Parallel facial recognition system based on optical joint transform correlator,” in Conference on Lasers and Electro-Optics CLEO/Pacific Rim ’97, Technical Digest (Institute of Electrical and Electronics Engineers, New York, 1997), paper FK3, pp. 276–277.
[CrossRef]

Keeni, K.

K. Keeni, H. Shimodaira, T. Nishino, S. Makino, Y. Tan, “Recognition of Devanagari characters using neural network,” IEICE Trans. Inf. Sys. E79-D, 523–528 (1996).

Kodate, K.

K. Kodate, E. Tokunaga, Y. Tatuno, J. Chen, T. Kamiya, “Efficient zone plate array accessor for optoelectronic integrated circuits: design and fabrication,” Appl. Opt. 29, 5115–5119 (1994).
[CrossRef]

R. Thapliya, A. Hashimoto, K. Kodate, M. Tsuchiya, T. Kamiya, “Parallel optical processing applied to character recognition,” in Conference on Lasers and Electro-Optics CLEO/Pacific Rim ’97, Technical Digest (Institute of Electrical and Electronics Engineers, New York, 1997), paper FW4, pp. 310–311. (Part of this study was reported orally.)
[CrossRef]

K. Kodate, A. Hashimoto, Y. Takahashi, R. Thapliya, T. Kamiya, “Parallel facial recognition system based on optical joint transform correlator,” in Conference on Lasers and Electro-Optics CLEO/Pacific Rim ’97, Technical Digest (Institute of Electrical and Electronics Engineers, New York, 1997), paper FK3, pp. 276–277.
[CrossRef]

R. Thapliya, K. Kodate, M. Tsuchiya, T. Kamiya, “Character recognition of Sanskrit scripts using joint transform correlator,” in 1996 International Topical Meetings on Optical Computing, Technical Digest (Japan Society of Applied Physics, Tokyo, 1996), Vol. 1, paper OThB4, pp. 246–247.

Kuo, C. J.

C. J. Kuo, “Joint transform correlator improved by means of a frequency-selective technique,” Opt. Eng. 33, 522–527 (1994).
[CrossRef]

Li, J.

J. Li, Y. Wang, J. Hu, “Experimental investigation of real-time nonlinear joint transform correlator,” Opt. Eng. 33, 3302–3305 (1994).
[CrossRef]

Lu, G.

Lu, T.

Mahabala, H. N.

R. M. K. Singh, H. N. Mahabala, “Machine recognition of Devanagari script,” IEEE Trans. Sys. Man Cybern. SMC-9, 435–441 (1979).

Makino, S.

K. Keeni, H. Shimodaira, T. Nishino, S. Makino, Y. Tan, “Recognition of Devanagari characters using neural network,” IEICE Trans. Inf. Sys. E79-D, 523–528 (1996).

Matsuoka, K.

Y. Ichioka, T. Iwaki, K. Matsuoka, “Optical information processing and beyond,” Proc. IEEE 84, 694–719 (1996).
[CrossRef]

Minemoto, T.

Q. Zhan, T. Minemoto, “Successful pattern matching with a large number of reference patterns using a joint transform correlator,” Jpn. J. Appl. Phys. 32, 3471–3476 (1993).
[CrossRef]

Neifeld, M. A.

Nishihara, E.

Nishikawa, T.

Nishino, T.

K. Keeni, H. Shimodaira, T. Nishino, S. Makino, Y. Tan, “Recognition of Devanagari characters using neural network,” IEICE Trans. Inf. Sys. E79-D, 523–528 (1996).

Psaltis, D.

Shamir, J.

J. Shamir, Trends in Optics Research, Developments and Applications (Academic, New York, 1996), Chap. 13.

Shang, L.

Shimodaira, H.

K. Keeni, H. Shimodaira, T. Nishino, S. Makino, Y. Tan, “Recognition of Devanagari characters using neural network,” IEICE Trans. Inf. Sys. E79-D, 523–528 (1996).

Singh, R. M. K.

R. M. K. Singh, H. N. Mahabala, “Machine recognition of Devanagari script,” IEEE Trans. Sys. Man Cybern. SMC-9, 435–441 (1979).

Takahashi, Y.

K. Kodate, A. Hashimoto, Y. Takahashi, R. Thapliya, T. Kamiya, “Parallel facial recognition system based on optical joint transform correlator,” in Conference on Lasers and Electro-Optics CLEO/Pacific Rim ’97, Technical Digest (Institute of Electrical and Electronics Engineers, New York, 1997), paper FK3, pp. 276–277.
[CrossRef]

Tam, E. C.

Tan, Y.

K. Keeni, H. Shimodaira, T. Nishino, S. Makino, Y. Tan, “Recognition of Devanagari characters using neural network,” IEICE Trans. Inf. Sys. E79-D, 523–528 (1996).

Tang, Q.

Tatuno, Y.

Thapliya, R.

R. Thapliya, M. Tsuchiya, T. Kamiya, “Joint transform correlator applied to recognition of Devanagari script,” Opt. Rev. 3, 397–399 (1996).
[CrossRef]

R. Thapliya, “Optical processing applied to recognition of Devanagari script,” Master’s thesis (University of Tokyo, Tokyo, Japan, March1996), Chap. 3.

R. Thapliya, A. Hashimoto, K. Kodate, M. Tsuchiya, T. Kamiya, “Parallel optical processing applied to character recognition,” in Conference on Lasers and Electro-Optics CLEO/Pacific Rim ’97, Technical Digest (Institute of Electrical and Electronics Engineers, New York, 1997), paper FW4, pp. 310–311. (Part of this study was reported orally.)
[CrossRef]

R. Thapliya, K. Kodate, M. Tsuchiya, T. Kamiya, “Character recognition of Sanskrit scripts using joint transform correlator,” in 1996 International Topical Meetings on Optical Computing, Technical Digest (Japan Society of Applied Physics, Tokyo, 1996), Vol. 1, paper OThB4, pp. 246–247.

K. Kodate, A. Hashimoto, Y. Takahashi, R. Thapliya, T. Kamiya, “Parallel facial recognition system based on optical joint transform correlator,” in Conference on Lasers and Electro-Optics CLEO/Pacific Rim ’97, Technical Digest (Institute of Electrical and Electronics Engineers, New York, 1997), paper FK3, pp. 276–277.
[CrossRef]

Tokunaga, E.

Tsuchiya, M.

R. Thapliya, M. Tsuchiya, T. Kamiya, “Joint transform correlator applied to recognition of Devanagari script,” Opt. Rev. 3, 397–399 (1996).
[CrossRef]

R. Thapliya, A. Hashimoto, K. Kodate, M. Tsuchiya, T. Kamiya, “Parallel optical processing applied to character recognition,” in Conference on Lasers and Electro-Optics CLEO/Pacific Rim ’97, Technical Digest (Institute of Electrical and Electronics Engineers, New York, 1997), paper FW4, pp. 310–311. (Part of this study was reported orally.)
[CrossRef]

R. Thapliya, K. Kodate, M. Tsuchiya, T. Kamiya, “Character recognition of Sanskrit scripts using joint transform correlator,” in 1996 International Topical Meetings on Optical Computing, Technical Digest (Japan Society of Applied Physics, Tokyo, 1996), Vol. 1, paper OThB4, pp. 246–247.

VanderLugt, A.

A. VanderLugt, “Signal detection by complex spatial filtering,” IEEE Trans. Inf. Theory IT-10, 139–145 (1964).

A. VanderLugt, Optical Signal Processing (Wiley, New York, 1992), Chap. 3.

Wang, J.

Wang, R. K.

Wang, Y.

J. Li, Y. Wang, J. Hu, “Experimental investigation of real-time nonlinear joint transform correlator,” Opt. Eng. 33, 3302–3305 (1994).
[CrossRef]

Yamamura, A.

Yu, F. T. S.

Zhan, Q.

Q. Zhan, T. Minemoto, “Successful pattern matching with a large number of reference patterns using a joint transform correlator,” Jpn. J. Appl. Phys. 32, 3471–3476 (1993).
[CrossRef]

Appl. Opt. (6)

IEEE Trans. Inf. Theory (1)

A. VanderLugt, “Signal detection by complex spatial filtering,” IEEE Trans. Inf. Theory IT-10, 139–145 (1964).

IEEE Trans. Sys. Man Cybern. (1)

R. M. K. Singh, H. N. Mahabala, “Machine recognition of Devanagari script,” IEEE Trans. Sys. Man Cybern. SMC-9, 435–441 (1979).

IEICE Trans. Inf. Sys. (1)

K. Keeni, H. Shimodaira, T. Nishino, S. Makino, Y. Tan, “Recognition of Devanagari characters using neural network,” IEICE Trans. Inf. Sys. E79-D, 523–528 (1996).

Jpn. J. Appl. Phys. (1)

Q. Zhan, T. Minemoto, “Successful pattern matching with a large number of reference patterns using a joint transform correlator,” Jpn. J. Appl. Phys. 32, 3471–3476 (1993).
[CrossRef]

Opt. Eng. (2)

J. Li, Y. Wang, J. Hu, “Experimental investigation of real-time nonlinear joint transform correlator,” Opt. Eng. 33, 3302–3305 (1994).
[CrossRef]

C. J. Kuo, “Joint transform correlator improved by means of a frequency-selective technique,” Opt. Eng. 33, 522–527 (1994).
[CrossRef]

Opt. Lett. (1)

Opt. Rev. (1)

R. Thapliya, M. Tsuchiya, T. Kamiya, “Joint transform correlator applied to recognition of Devanagari script,” Opt. Rev. 3, 397–399 (1996).
[CrossRef]

Proc. IEEE (2)

Y. Ichioka, T. Iwaki, K. Matsuoka, “Optical information processing and beyond,” Proc. IEEE 84, 694–719 (1996).
[CrossRef]

F. T. S. Yu, D. A. Gregory, “Optical pattern recognition: architectures and techniques,” Proc. IEEE 84, 733–752 (1996).
[CrossRef]

Other (8)

J. W. Goodman, Introduction to Fourier Optics, 2nd ed. (McGraw-Hill, New York, 1996), Chap. 8.

J. Shamir, Trends in Optics Research, Developments and Applications (Academic, New York, 1996), Chap. 13.

J. L. Horner, “Single SLM joint transform correlator,” U.S. patent5,040,140 (13August1991).

R. Thapliya, A. Hashimoto, K. Kodate, M. Tsuchiya, T. Kamiya, “Parallel optical processing applied to character recognition,” in Conference on Lasers and Electro-Optics CLEO/Pacific Rim ’97, Technical Digest (Institute of Electrical and Electronics Engineers, New York, 1997), paper FW4, pp. 310–311. (Part of this study was reported orally.)
[CrossRef]

R. Thapliya, K. Kodate, M. Tsuchiya, T. Kamiya, “Character recognition of Sanskrit scripts using joint transform correlator,” in 1996 International Topical Meetings on Optical Computing, Technical Digest (Japan Society of Applied Physics, Tokyo, 1996), Vol. 1, paper OThB4, pp. 246–247.

K. Kodate, A. Hashimoto, Y. Takahashi, R. Thapliya, T. Kamiya, “Parallel facial recognition system based on optical joint transform correlator,” in Conference on Lasers and Electro-Optics CLEO/Pacific Rim ’97, Technical Digest (Institute of Electrical and Electronics Engineers, New York, 1997), paper FK3, pp. 276–277.
[CrossRef]

A. VanderLugt, Optical Signal Processing (Wiley, New York, 1992), Chap. 3.

R. Thapliya, “Optical processing applied to recognition of Devanagari script,” Master’s thesis (University of Tokyo, Tokyo, Japan, March1996), Chap. 3.

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Figures (7)

Fig. 1
Fig. 1

Experimental setup of a PJTC with zone-plate array multiplication optics. (The CCD camera is to be replaced by a dedicated photodetector array.) Data communication from–to the PC only for preprocessed target images and for correlation signals.

Fig. 2
Fig. 2

Schematic diagram of a five-channel FZPA with irregular channel positioning, taking into account the pixelated structure of the ESLM.

Fig. 3
Fig. 3

Typical experimental JPS array formed by an irregular FZPA to avoid diffraction-order overlapping. (The notations given by △, ▿, □, ◇, and ○ are the orders created by channels 1, 2, 3, 4, and 5, respectively.)

Fig. 4
Fig. 4

(a) Flowchart of the PJTC with optical multiplication and photographic referencing. (b) Picture of multichannel correlation signals monitored by a CCD camera. (c) Beam profiles of each correlation signal.

Fig. 5
Fig. 5

Reduction of redundant information by feature extraction of core characters from 64 × 64 to 25 × 25 pixels.

Fig. 6
Fig. 6

Worst-case cross-correlation peaks for (a) full-size characters and (b) partial characters. (Autocorrelations are designated by the dotted curves.)

Fig. 7
Fig. 7

Projected PJTC with pulsed-laser-driven optical disk referencing.

Tables (3)

Tables Icon

Table 1 Specifications of the Citizen Watch Company’s LC ESLM

Tables Icon

Table 2 Specifications of the Experimental Setup

Tables Icon

Table 3 Experimental Study of Cross-Correlation Signal-Height Distribution for All Partial Characters (38 × 38 = 1444)

Equations (9)

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

f LCSLM x ,   y = rect x L x rect y L y n = - m = -   δ x - n L x + t x ,   y - m L y + t y ,
f JTC x ,   y = r x ,   y δ x - a ,   y + s x ,   y δ x + a ,   y ,
f inp x ,   y = f LCSLM x ,   y f JTC x ,   y .
| F in u ,   v | 2 = L x L y 2 sinc 2 π L x λ f   u sinc 2 π L y λ f   v Envelope Function ¯ n = - m = -   δ u - λ f L x + t x   n ,   v - λ f L y + t y   m Comb Function ¯ | F JTC 2 π / λ f u ,   2 π / λ f v | 2 . JPS ¯
N pE C N pO .
ψ x ,   y ;   1 f exp j   π λ f x 2 + y 2 ,
d ψ * x ,   y ;   d d   exp - j   π d λ x 2 + y 2 ,
g r ,   s = d 1 d 2 P 1 P 2   f x ,   y ψ x ,   y ;   1 / f 3 × ψ * u - x ,   v - y ;   d 1 ψ * u ,   v ;   1 / f 4 × ψ * r - u ,   s - v ;   d 2 d x d y d u d v ,
g r ,   s = d 1 d 2 - d 1 d 2 - d 1 / f 4 + d 1 / f 3 + d 2 / f 3 + 1 / f 3 f 4 × ψ * r ,   s ;   d 2 2 d 1 - 1 / f 3 - d 1 d 2 - d 1 / f 4 + d 1 / f 3 + d 2 / f 3 + 1 / f 3 f 4 × f - d 2 d 1   r ,   - d 2 d 1   s .

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