所有的光場都是隨機漲落的,有些光場的隨機漲落很小,例如許多激光器輸出的光;有些光場的隨機漲落相當大,例如從熱光源輻射的光。描述漲落光場的基礎(chǔ)理論是相干理論。部分偏振現(xiàn)象就是漲落的重要表現(xiàn)。實際上,相干理論所能處理的問題不僅限于漲落。與常規(guī)的處理方法不同,相干理論是依據(jù)可觀測量描述光場,并解釋這些可觀測量,例如光的光譜以及它在傳輸中如何變化的。
《光的相干與偏振理論導(dǎo)論(英文影印版)》給出了光的相干與偏振現(xiàn)象的統(tǒng)一處理方法。適合光通信、激光光束在光纖中和通過湍流大氣傳輸、光學(xué)成像,尤其在顯微鏡成像(例如醫(yī)學(xué)診斷)的物理界和工程界的研究者閱讀。
光的相干和偏振是光學(xué)中最重要的現(xiàn)象,其應(yīng)用也極為廣泛。《光的相干與偏振理論導(dǎo)論(英文影印版)》的作者是國際光學(xué)界的著名學(xué)者,在相關(guān)的研究取中取得過突破性的進展。也正是因為作者的貢獻,本書能夠以統(tǒng)一處理方法研究光的相干與偏振這兩種現(xiàn)象。對于光通信、光學(xué)成像等領(lǐng)域的研究者及研究生,乃至對此領(lǐng)域感興趣的讀者來說,本書是不可多得的優(yōu)秀讀物。
(美) 沃爾夫(E. Wolf),美國羅徹斯特大學(xué)教授。
Preface page xi
1. Elementary coherence phenomena 1
1.1 Interference and statistical similarity 1
1.2 Temporal coherence and the coherence time 4
1.3 Spatial coherence and the coherence area 5
1.4 The coherence volume 8
Problems 10
2. Mathematical preliminaries 11
2.1 Elementary concepts of the theory of random processes 11
2.2 Ergodicity 17
2.3 Complex representation of a real signal and the envelope
of a narrow-band signal 19
2.4 The autocorrelation and the cross-correlation functions 22
2.4.1 The autocorrelation function of a finite sum of periodic
components with random amplitudes 24 Preface page xi
1. Elementary coherence phenomena 1
1.1 Interference and statistical similarity 1
1.2 Temporal coherence and the coherence time 4
1.3 Spatial coherence and the coherence area 5
1.4 The coherence volume 8
Problems 10
2. Mathematical preliminaries 11
2.1 Elementary concepts of the theory of random processes 11
2.2 Ergodicity 17
2.3 Complex representation of a real signal and the envelope
of a narrow-band signal 19
2.4 The autocorrelation and the cross-correlation functions 22
2.4.1 The autocorrelation function of a finite sum of periodic
components with random amplitudes 24
2.5 The spectral density and the Wiener-Khintchine theorem 25
Problems 29
3. Second-order coherence phenomena in the space-time domain 31
3.1 Interference law for stationary optical fields. The mutual
coherence function and the complex degree of coherence 31
3.2 Generation of spatial coherence from an incoherent source.
The van Cittert-Zernike theorem 37
3.3 Illustrative examples 46
3.3.1 Michelson's method for measuring stellar diameters 46
3.3.2 Michelson's method for determining energy distribution
in spectral lines 51
3.4 Propagation of the mutual intensity 54
3.5 Wave equations for the propagation of mutual coherence in free space 56
Problems 58
4. Second-order coherence phenomena in the space-frequency domain 60
4.1 Coherent-mode representation and the cross-spectral density
as a correlation function 60
4.2 The spectral interference law and the spectral degree of coherence 63
4.3 An illustrative example: spectral changes on interference 69
4.4 Interference of narrow-band light 73
Problems 76
5. Radiation from sources of different states of coherence 79
5.1 Fields generated by sources with different coherence properties 79
5.2 Correlations and the spectral density in the far field 81
5.3 Radiation from some model sources 88
5.3.1 Schell-model sources 88
5.3.2 Quasi-homogeneous sources 90
5.4 Sources of different states of spatial coherence which generate
identical distributions of the radiant intensity 95
5.5 Coherence properties of Lambertian sources 97
5.6 Spectral changes on propagation. The scaling law 102
Problems 108
6. Coherence effects in scattering 111
6.1 Scattering of a monochromatic plane wave on a deterministic medium 111
6.2 Scattering of partially coherent waves on a deterministic medium 115
6.3 Scattering on random media 118
6.3.1 General formulas 118
6.3.2 Examples 121
6.3.3 Scattering on a quasi-homogeneous medium 123
Problems 127
7. Higher-order coherence effects 129
7.1 Introduction 129
7.2 Intensity interferometry with radio waves 131
7.3 The Hanbury Brown-Twiss effect and intensity interferometry with light 134
7.4 Einstein's formula for energy fluctuations in blackbody radiation
and the wave-particle duality 140
7.5 Mandel's theory of photoelectric detection of light fluctuations 143
7.5.1 Mandel's formula for photocount statistics 143
7.5.2 The variance of counts from a single photodetector 145
7.5.3 Correlation between count fluctuations from two detectors 147
7.6 Determination of statistical properties of light from photocount
measurements 149
Problems 151
8. Elementary theory of polarization of stochastic electromagnetic beams 154
8.1 The 2 _ 2 equal-time correlation matrix of a quasi-monochromatic
electromagnetic beam 154
8.2 Polarized, unpolarized and partially polarized light. The degree
of polarization 158
8.2.1 Completely polarized light 158
8.2.2 Natural (unpolarized) light 160
8.2.3 Partially polarized light and the degree of polarization 161
8.2.4 The geometrical significance of complete polarization. The Stokes
parameters of completely polarized light. The Poincaré sphere 165
Problems 171
9. Unified theory of polarization and coherence 174
9.1 The 2 _ 2 cross-spectral density matrix of a stochastic
electromagnetic beam 174
9.2 The spectral interference law, the spectral degree of coherence
and the spectral degree of polarization of stochastic
electromagnetic beams 175
9.3 Determination of the cross-spectral density matrix from experiments 179
9.4 Changes in random electromagnetic beams on propagation 181
9.4.1 Propagation of the cross-spectral density matrix of a stochastic
electromagnetic beam - general formulas 181
9.4.2 Propagation of the cross-spectral density matrix of an
electromagnetic Gaussian Schell-model beam 183
9.4.3 Examples of correlation-induced changes in stochastic
electromagnetic beams on propagation 186
9.4.4 Coherence-induced changes of the degree of polarization
in Young's interference experiment 191
9.5 Generalized Stokes parameters 194
Problems 197
Appendices 202
I Cells of phase space and the degeneracy parameter 202
(a) Cells of phase space of a quasi-monochromatic light wave (Section 1.4) 202
(b) Cells of phase space of radiation in a cavity (Sections 7.4 and 7.5) 204
(c) The degeneracy parameter 206
II Derivation of Mandel's formula for photocount statistics
[Eq. (2) of Section 7.5.1] 208
III The degree of polarization of an electromagnetic Gaussian
Schell-model source 210
IV Some important probability distributions 212
(a) The binomial (or Bernoulli) distribution and some of its limiting cases 212
(b) The Bose-Einstein distribution 214
Author index 216
Subject index 220