Because the adaptive optical system is often used to correct wave-front of annular beam, six annular configurations of the wave-front sensor subaperture and the deformable mirror actuator have been simulated, and the principle of annular configuration is presented. The annular configuration are compared with the squared configuration. It shows that the annular configuration is more suitable for the annular beam.

We carried out a series of measurments of the irradiance scintillation of a He-Ne laser beam propagating through a real turbulent atmosphere in a whole year. The statistical properties of the irradiance scintillation, such as the scintillation index, the probabitity distribution, and the power spectrum were analysed. The effect of detector saturation on the accuracy of the measurment data was discussed.

Considering the cladding modes as far from cut off, the intermodal coupling between guided and cladding modes by long-period fiber gratings is analysed using coupled modes theory, and compared with that of short-period fiber gratings. It is pointed out that the properties of long period fiber grating are related to its phase matching condition. Computation results show good consistent with experiments.

A novel method that can lead to generation of intense ultrashort optical solitons from weak pulses in the anomalous-dispersion regime of single-mode fibers is proposed. It consists of copropagating a weak pulse with an intense pump pulse in an optical fiber whose minimum-dispersion wavelength is chosen such that it falls between the pump and the signal wavelength. The interplay between Raman amplification and pulse compression induces the week pulse to evolve into several fundamental solitons whose widths are much narrower than those of pump pulse and initial signal pulse. Numerical simulations show that, the higher the pump power is, the narrower and more intense the generated soliton is, and a shorter fiber is used. It is also shown that the method remains applicable even for different initial widths and for a small walk-off between the pump and the signal pulses. Finally, the mechanism for fundamental soliton generation and its application in optical soliton communication system are discussed.

The characteristics of phase-sensitive soliton switching in optical fiber couplers have been studied analytically by using dynamical method. Transmission behaviors of the main pulse will be dramatically controlled by the initial phase of a relative weak soliton in another fiber core. Different switching properties will be obtained, provided the initial solitons phases into two fiber cores are slected appropriately.

We studied partial coherent X-ray in-line Gabor holography and obtained the relation between coherent degree and resolution(contrast). Both transverse and longitudinal resolution and image contrast decrease when the degree of coherence decrease. A requirement on the coherent length for making high quality holographic imaging is presented.

According to the principle of electronic holography using ultrashort laser-pulse for imaging through highly scattering media, an electronic holography system is established which is suitable for imaging through highly scattering media. This system consists of CCD camera, imaging processor and program of the system for numerical reconstructing and image process. Using this system, an image of metal wire with diameter of 0.65 mm has been obtained, through a 12 mm thick scattering liquid mixture of fresh milk and water. The volume ratio of fresh milk and water is 5%. The demand of this technique on pulse-width is analyzed.

In the process of infrared imaging testing, the computer aided method for high power noise reduction has been proposed according to the characteristic of linear differential equation and two approximations. The method is proved effective by computer simulation.

A novel method is presented to reconstruct the wavefront with phase distortion in STRALIGHT II 1012 W high power laser apparatus by means of computer image processing. In experiments, the image processing of optical spots fired on photograph by high power laser beams through a plate with hole array. The iteration formula group was deduced to apply in the experiments. Each center of intensitv of optical spots and relative shift were measured, and phase wavefront of high power laser was reconstructed in iteration. Computer software made the focusing procedure of small optical beams in hole array instead of which in sub-lens array of normal Hartmann-Shack sensor. The method can be used to measure directly the high power laser beam with large diameter. The principle and the formula of the reconstruction are described. The method has been used in the experiments of the high power laser apparatus STARLIGHT ⅠⅠ. The maximum diameter measured is 200 mm,and the resolving power of wavefront reconstruction is about λ/5.

The defects survey experiment for the adhesion quality of composite material with large size has been carried out by using the techniques of single-mode optical fiber and thermogram. Its new mechanism is discussed and analysed.

The influence of the thermal effect on a Kerr-lens mode-locked laser cavity is discussed. By numerical calculation, some results have been obtained, which include the variation of spot size with the normalized pulse power and relative beam-width sensitivity to the normalized pulse power when thermal effect exists. The influences of Kerr effect and thermal effect in the laser cavity are discussed and the condition of the Kerr lens mode locking insensitive to the thermal effects is given.

Based on the semi-classical theory and Maxwell-Bloch equations, the amplification of the seed pulse in the laser regenerative and multi-pass amplifiers is analyzed. The analytical expression of the peak fluence is obtained by assuming some actual physical conditions. A relationship between the enhancement and stability of the peak output and the gain, loss of the amplifier is discussed in detail. The results are instructive to the actual establishment.

The threshold of optical parametric oscillator is critically relevant to the beam quality of pumping laser, the phase conjugate effect of stimulated Brillouin scattering is applied to the ruby pumping laser system of KTP optical parametric oscillator. The threshold was reduced to 25%～7% of the original one in the experiment.

The shortest pulse duration, to our knowledge, from a Ti:sapphire laser in low gain region is reported. Pumped by 8.9 W from the all-line of argon laser, a stable laser pulse train centred at 0.94 μm, with pulse duration of 37 fs, banwidth of 33 nm, average power of 80 mW and a tuning range of 0.9 μm to 0.976 μm have been obtained.

The X-ray emission from Al and Cu plasma generated by femtosecond and nanosecond laser pulses have been measured and comparied. The irradiaton intensities of fs and ns laser pulses are 8.9×1015 and 3.8×1011 W/cm2 respectively. The experimental results show that under fs laser irradiation the emission peak is shifted to shorter wavelength. The ionization stage and temperature of fs Al Plasma is higher than that produced by ns laser.

Single crystals of AgGa(Se1-xSx)2 with x=0.20, 0.50, 0.75 have been prepared, and some optical properties are presented. Calculation made for the type I optical parametric oscillation by 1.06 μm radiation pumping shows that mid-infrared laser continuously tunable from 1.4 to 12 μm can be generated for the crystal AgGa(Se1-xSx)2 with x=0.65.

Aliasing will occur when sampling a scene containing spatial frequencies exceeding half of the sampling frequency. An optical method, referred as optical prefiltering, for reducing aliased signal energy in discrete imaging systems is proposed and discussed. Pupil function for producing the expected prefiltering effect is deduced. Simulation results are presented to illustrate the effectiveness of optical prefiltering method.

The transmission properties of collimating lenses for semiconductor laser beams are analysed and the main factors to influence the beam quality of the collimated semiconductor laser beam are discussed. The highly collimated semiconductor laser beams are obtained by using the small aperture lenses with large numerical aperture.

When the axicon is tilted, the incident plane wave focused by it does not form a Bessel distribution diffraction pattern again. The Kirchholf diffraction formula is needed to analyze the diffraction result. Some higher term concerning with the tilted angle in the expansion of phase exponent should be retained. After conducting, an integral about φ can be obtained. The integral result fitted with the real diffraction pattern very well. Numeral simulation and experimental result agree with each other. The diffraction pattern formula can be used to estimate the adjustment permissible error of axicon in application.

Two ceramic thick film electroluminescent (CTFEL) devices with or without Y2O3 which using the tetrad system PMN-PCW-PFN-PT ceramic thick film as insulator have been prepared. The CTFEL devices can be driven at 50 Hz between 30～110 Volts, and may be used as indicator or label lamp in safety electricity net. The electroluminescent performance of the EL devices with the different processing of ceramic thick film has been investigated in detail. It is indicated that the brightness of the CTFEL device with Y2O3 as insulator was higher than that without Y2O3 as insulator.

A novel optical limiting device is proposed. The device consists of an organic solution sandwiched between two transmitted relief gratings with different grove sturcture. The refraction index of the liquid is matched with that of grating material. The device has a high transmittance under the common light. However, the strong laser will make the liquid to thermally vaporize, index mismatch, and two gratings appear. The incident light will be total reflected and scattered by the front grating, then it will be strongly absorbed, scattered and self-focused by the organic solution. Finally, the rear grating will suppress the zero-order diffraction, let the transmitted light energy lower than the damage threshold of human eyes. Therefore, the device provides an effective protection of eyes against the broadband pulsed laser damage.

A new experiment was carried out for studying the interaction of high intensity laser with microcapillaries by using an ultra-short high intensity laser with 45 fs pulse width. X-ray spectra of stainless steel microcapillary and glass microcapillary are obtained successfully. An X-ray source with good direction and 10 Hz repetition rate is created.

A method for dealing with a kind of elliptical Gaussian beam which has simple astigmatic character is discussed, and two across cylindrical lens are used to imitate a spherical biaxial lens on transforming the beam from a semiconductor laser. A fairly perfect result is obtained that elliptical Gaussian beam is transformed into an approximately similar circular Gaussian beam.

The correction of phase error is an important step in the calculation of Fourier transform spectrum. The problem of computation efficiency of the commonly used phase correction method, Mertz method, is studied in detail. By applying the quality of real serial Fast Fourier Transform (FFT) and combining it with the computing process, an improved algorithm is obtained, which demonstrates greater computation efficiency and is easier to use.

Femtosecond luminescence dynamics of poly (phenylacetylene) (PPA) and poly (1-phenyl-1-butyl) (PPB) were investigated. PPA shows much larger red shift (～160 meV) of luminescence spectrum than PPB (～60 meV). Ultrafast energy-dependent luminescence decay was observed in PPA, but it is absent for PPB. We attribute the luminescence dynamics observed in PPA and PPB to the exciton migration within the inhomogeneous distribution of conjugated chains. The length of side groups plays an important role in the luminescence dynamics of substituted polyacetylenes.

The design and testing of the soft X-ray multilayer beam-splitters are presented. The beam-splitters of Mo/Si multilayer with a large area by etching substrate and separating multilayer from substrate with NaCl coating are fabricated.