A new method, double filtering with two filter masks, is proposed to perform the Fourier-transform quasi-interferometry. In this way, some complex filter functions can be synthesized in a Moire equivalence from two comparatively simple filter functions. Furthermore, the resultant filter function can be contiuously changed by moving the masks along the optical axis, thus giving remarkable flexibility in practical applications.

Effects of either spatially or temporally partial coherence on the image quality of a microscope are considered in this paper. Calculation results indicate that under partially coherent illumination the image contrast will be lower than that under coherent illumination, but it can be improved by utilizing a carefully designed light source,a special spatial filter.

Proceeding from the analysis of the alignment error, the author study the conditional relationship between the "equivalent line width of the dispersion for the step function edge,the "equivalent bandwidth" of the system, known as the uncertainty relationship for the optical systems. The measurement results are given. The equivalent line width,the equivalent bandwidth beq can be considered as the assessment critia of the imaging quality for the optical systems with small aberrations.

This paper presents a new type resonator-spherical resonant cavity, which consists of a spheric medium,its interface with surrounding medium. The intrinsic modes, mode frequencies,the internal field of this spherical cavity are discssed, It is pointed out that this kind of cavity can be used as a good optical resonantor. Finally, the spectrum,angular distribution of elastic scattering from the spherical droplet are given.

We have detailed experimental studies on a colliding pulse mode-locked Nd:YAG laser. Operating characteristics of the laser under different conditions of position, thickness, concentration of saturates absorber,,pumping energy are given Mode-locked light pulses with duration of 11-12 ps can routinely be obtained from. this laser.

An acousto-optic modulator is used for active mode-locking in a discharge-heated CuCl laser. The modulation depth of 100%,the pulse-width of 2ns are obtained. The laser repetition frequency is 16-kHz,the probability of mode-locking is about 100%.

The analytic expression for bunching pontential was derived according to Lorentz equations,the requirement that the force be equal to the minus gradient of the pontential. The energy transfer between a relativistic electron,the radiation field is equivalent to the electron energy variation in this space potential well,,the maximum energy lost by the electron in this potential well is proportional to the depth of the well. In order to increase the energy transfer efficiency, it is required that t...

Experimental study on (F2+)* centers in NaF:Mg2+ crystals is reported in this paper. A process of type transfer from F2+ to (F26+)* centers was observed in our ex Periment. The rate of transfer depends on the type of doped divalent metal ions rather than the concentration of doped cations. It was also found that the products of thermal bleaching of the(F2+)* centers exhibit the same properties as that of Z4 centers. From the results of experiments we propose a possible model that the (F2+)* center is formed of a F2+ center connected to an I-V pair.

The energy levels,spectroscopic characteristics of Y3Ga5O12:Cr3+ crystal grown by flux method are reported. At room temperature, the effective fluorescence lifetime of 4T2,2E levels was measured to be 205μs with the central wavelength of the fluorescence spectrum of 727nm. The crystal-field energy levels, were calculated according to Tanabe-Sugano theory. The crystal field strength parameter Dq, racah paramater B,C,parameter A were calculated to be 1626, 645, 2950,538 cm-1, respectively.

The quatum-statistical properties of an absorptive optical system driven by a partially coherent field are investigated. As the coherent component of the input field increases from zero, the intensity fluctuation of the output light may be slightly enhanced, i.e., the output field becomes less coherent as the input field becomes more coherent. This abnormal behaviour is caused by the phase fluctuation of the input light. In the low noise limit, the location,value of the maximum of the second-order correlation function for the input field are given analytically by means of the Gaussian approximation. In the Jiigh noise limit, an explicit expression of the second-order correlation function is also obtained.

Three optical invariants of graded-index optical fibers,the ray equation in a fiber cross section have been derived. Examples are given for several special cases. The results obtained here are in good agreement with previous theoretical calculations. The method,results are useful in designing refractive index profiles of fibers.

This paper reports the spectral,lasing characteristics of R560 using a XeCl excimear laser,a YAG:Nd laser as pump sources. R560 is one of the Rhodamines synthesized by this group. In our experiments a diffraction grating is used in the dye laser resonator as frequency selection element, which is at grazing incidence in order to minimize the line-width. In this way, we have obtained a linewidth of about 0.1 A. As it has good spectral characteristics, such dye can be used in practical lasers.

The coordination states of aluminium,boron in Na2O-Al2O3-BaO3-P2O5 glasses have been studied by means of Raman spectroscopy. The study shows that when boron,aluminium ions coexist in phosphate glasses, it is possible that boron iong form BO4 tetrahedra prior to aluminium ions, with the former having three or four coordinations,the latter having four or six.

Approximating fundamental mode of graded-index fibers by Gaussian-modified Bessel function, the power coupling between two neighboring graded-index single-mode fibers is calculated. Coupling coefficient formula is derived,curves of the coupling coefficients as a function of distance D with different F values,exponent g of power law-index are plotted. Comparing these results for step-index (as a limit of g = ∞) with Snyder s results which suit to step-index only, we see that Gaussian-modified Bessel approximation is better than Gaussian approximation in dealing with evanesent coupling problems.

CS2 mnltiphoton ionization (MPI) mass spectra induced by a XeCl laser are reported. The dependence of ion intensity on laser intensity,sample pressure is measured. Based on the experimental results,some calculations, the MPI model of CS2,the forming pathways of ions are described.

In this paper, requirements on recording sinogram in hybrid optical digital processing X-ray tomography are analysed. The method of correcting sinogram data is described. We have investigated the effect of film granularity on the noise of reconstructed images,,have derived an expression of signal-to-noise ratio. Finally the experimental results for reconstructed images are given.