Browse > Article

Improvement of the Signal-to-Noise Ratio of Photorefractive Joint Transform Correlator using Characteristics of $BaTiO_3$  

공명술 (경북대학교 전자전기컴퓨터학부)
서동환 (경북대학교 전자전기컴퓨터학부)
신창목 (경북대학교 전자전기컴퓨터학부)
조규보 (경북대학교 전자전기컴퓨터학부)
김철수 (경북대학교 컴퓨터전자공학부)
김수중 (경북대학교 전자전기컴퓨터학부)
Publication Information
Journal of the Institute of Electronics Engineers of Korea SD / v.40, no.3, 2003 , pp. 19-32 More about this Journal
Abstract
In the conventional photorefractive joint transform correlator(PRJTC), the intensity ration of input signal-to-pump beam should be large enough to saturate two-beam coupling transfer function to obtain a desired correlation result. As a result, the signal-to-noise ratio(SNR) of correlation result is decreased in a noisy input image. In this paper, we propose the improved method for increasing the SNR of the PRJTC by using the characteristics of BaTiO$_3$. We stop the energy transfer saturating by low intensity ratio of input beam and realize a short length of effective interaction in BaTiO$_3$ by making large incident angle of the signal beam. So the gain in high frequency area is decreased and the gain in low frequency area comes up to the saturation gain of the beam coupling transfer function. Therefore the SNR is improved in noisy input image and the PRJTC can be easily realized by low intensity ratio of input beam.
Keywords
Joint transform correlator(JTC); photorefractive material; two-beam coupling; signal-to-noise ratio(SNR);
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
연도 인용수 순위
1 J. W. Goodman, Introduction to Fourier Optics, Mcgraw-Hill, New York, 1968
2 B. V. K. V. Kumar and L. Hassebrook, 'Performance measurement of correlation filters,' Appl. Opt., Vol. 29, pp. 2997-3006, 1990   DOI
3 J. Feinberg, D. Heiman, A. R. Tanguay, Jr., and R. W. Hellwarth, 'Photorefractive effects and light-induced charge migration in barium titanate,' J. Appl. Phys., Vol. 51, pp. 1297-1305, 1980   DOI   ScienceOn
4 C. S. Weaver and J. W. Goodman, 'Technique for optically convolving two functions,' Appl. Opt., Vol. 5, pp. 1248-1249, 1966   DOI
5 김성완, 김철수, 김종찬, 김종윤, 이승희, 김수중, '변이불변 특성이 개선된 광굴절 상관기를 이용한 실시간 광 패턴인식 시스템의 구현,' 대한전자공학회 논문지, 제 35D권 제 3호, pp. 63-69, 1998   과학기술학회마을
6 R. Tripathi, G. S. Pati, K. Singh, 'Photorefractive joint transform correlator using incoherent erasure in two-and four-wave mixing geometries in a $BaTiO_3$ crystal,' Opt. Eng., Vol. 37, pp. 2148-2155, 1998   DOI   ScienceOn
7 J. Khoury, M. Cronin-Golomb, P. D. Gianino, and C. L. Woods, 'Photorefractive two-beam-coupling nonlinear joint-transform correlator,' J. Opt. Soc. Am. B, Vol. 11, pp. 2167-2174, 1994   DOI   ScienceOn
8 B. Javidi, 'Nonlinear joint power spectrum based optical correlation,' Appl. Opt., Vol. 28, pp. 3106-3111, 1989   DOI
9 B. Javidi and J. Wang, 'Limitation of the classic definition of the correlation signal-to-noise ratio in optical pattern recognition with disjoint signal and scene noise,' Appl. Opt., Vol. 31, pp. 6826-6829, 1992   DOI
10 T. Tschudi, A. Herden, J. Goltz, H. Klumb, F. Laeri, and J. Albers, 'Image amplification by two-and four-wave mixing in $BaTiO_3$ photorefractive crystals,' IEEE. J. of Quan. Elec., Vol. QE-22, No. 8, pp. 1493-1502, Aug. 1986   DOI