On the basis of communication theory, the method of backward impulse responseis proposed to explain the phenomena of interference with an extended white light source. In this treatment, the mathematics is Simple while the physical meaning becomes clearer. In addition it is possible to reach a unified point of view. The following two examples will be demonstrated: 1) imaging interferometers, and 2) Lau effect and grating imaging. In the present paper, only the former is discussed. In this paper a generalized model for the imaging interferometer is proposed in terms of the backward impulse response. The necessary condition for constructing the exact system is that the backward impulse response to the image point at the sonroe plane through both the active beamsplitter and the compensator must have a form of single wavefront. A generalized expression for the intensity distribution of the resultant interferogram is derived with the conclusion that the complex amplitude of the image point is proportional to the integral of the square of the backward impulse response at the object plane and the object phase variation. This response directly determines different kind of interference. Three configurations with amplitude division,, polarization division and diffraction division are analysed in detail. The effect of color fringes caused by the dispersion in polychromatic illumination is also discussed.

A general formula for computing the OTF of a defocused optical system is derived from the Kirchoff diffraction integration under an approximate condition which is weaker than the Fresnel condition. Abberations on Gaussian imaging plane and system defocussing are the parameters. The OTF s for a series of diffrently defocused imaging planes could be obtained by using this formula, avoiding a lot of abberation computing work for each actual imaging plane. Therefore this formula is very convenient for investigating the regularity of OTF of a dofooused optical system. In this paper a computational example is given.

Coherent propagation of two short optical pulses at different wavelengths in a two-level system driven by an intense laser beam is studied. An area theorem of the pulses has been obtained. The breakup of pulses in propagation and the phenomenon of mutual-induced transparancy have been found theoretically.

Interaction equations of light with a two-level atomic system have been derived under conditions of relaxation, damping and detuning. Simulation results are given about the propagation of coherent light pulses in a resonant absorbing medium. In addition to pulse breakup, a new phenomenon of two-pulse combination and the evolution of pulse area have been observed theoretically.

We have found some inappropriate points in calculating the effective NLO coefficients (deff) of biaxial crystals described in literature. The correct calculation method is developed. As an example the calculation method for biaxial crystals with symmetry of mm2 point group is presented in detail. These formulas have been borne out by experimental results. The calculation method makes it possible to design optimum phase matching for all kinds of biaxial crystals with a microcomputer.

By introducing the transmission function of MSllenstedt biprism into Kirchhoff diffraction integral, we have deduced the intensity distribution of an electron wave on the observation plane after passing through the biprism. Analytical expressions of distributions with both plane and spherical incident waves have been obtained. Some numerical results are presented, followed by a discussion on the dependence of the distribution on experimental parameters.

This paper describes a new theory and the related analysis method of "interference", which are quite different from the traditional Zernike three-beam interferometer. Formulas are given for calculating the optical transfer function of a three-beam system. Values of the optical transfer function and the accuracy of the system are also calculated.

This paper describes an opto-hetorodyne sine-ruler-type angle-measuring interferometer. It used a frequency-stabilized transverse Zeeman laser (STZL) as the light source. A method of sensitivity calibration for angle measurement is presented. Hysterisis characteristics of a PZT piezoelectric ceramic have been measured by using this angle-measuring interferometer.

Wave equations of a planar waveguide with Fermi index profile are studied theoretically. Analytical solutions have been obtained in terms of hypergeometric functions. It has been found that the characteristic equations can be expressed as rapidly converging infinite series of functions of the mode refractive index. Rather accurate results can be obtained by only taking the zeroth-order approximation.

Through analysis of π-phase edge image profiles, we obtain an incoherence factor x and propose an evaluation method for optical microscopes with evaluation parameter C. It has been found that the quality of the imaging system depends on a. Finally, comparisons are made between paramater C and Strehl ratio S. D.

The chance to observe optical damages in mode cut-off modulators used to be rare, because little optical power could be coupled into near-cut-off channel waveguides. The coupling capability, however, was found to be higher in our newly constructed three-section hybrid mode cut-off modulator, in which observable optical damage occured. Therefore, in designing guided-wave devices consisting of Ti-diffused waveguides, not only their electric characteristics but also their optical-power carrying capacity should be taken into consideration.

Theory of the spatially resolved optogalvanic effect in a CO-discharge positive column is given. The theory has been found to agree well with experimental results. Based on this theory, a new method for measuring spatial distributions of electron density (or gain) in positive columns of discharge by means of optogalvanic effects is proposed.

Combining a single-wavelength ellipsometer with a spectrophotometer, we propose a method to measure refractive indices of dielectric films at any wavelength. "With phase thickness of the thin film properly selected, the error of the measurement may be as low as <1×10-2, enough for the usual thin-film design and deposition.

In this paper a new laser system with an SBS phase conjugating mirror ig described. It consists of a Nd: YAG laser oscillator, a laser amplifier, and an SBS phaes conjugating mirror. A polarization discrimination technique is used to completely couple out the backward conjugating wave from the laser system. Effects of Brillouin cell geometry have been studied experimentally. By using acetone (300mm in length) as the scattering medium, Q-switched laser output of 100 mJ which compensated phase distortion has been obtained.

A reflection display method of rainbow holograms is discussed. A bright and sharp reconstructed image can be obtained by setting a high-reflectance metal film behind the hologram. A properly choiced bias transmittance of the hologram can lead to a diffraction efficiency close to or a little higher than that of transmission reconstruction. The distance between the metal film and the hologram should be determined carefully for a high-quality reconstructed image. Both theorectical analysis and experimental results are presented.

In this paper we discuss the feature selection in screening cervical cells by meang of optical power spectra. After analyzing morphological characteristics of normal cells and cancer cells and features of corresponding spectra, we have found the key for recognition. This feature alone can give a correct-recongition rate up to 94.5%, higher than the rate of 92% obtained before by using six features in a similar experiment[1]. We also present the relation between the correct-recognition rate and the dimension of feature space. The results indicate a fall-down of the correct-rate when the feature number Is increased improperly.