Mirrorless optical switching based on exited-state-absorption in C60/pMMA is studied. The experimental results are consistent with the theoretical simulations.

A new pre-burning circuit designed for 4×65 F pulsed xenon lamas is ptesented in this paper. Since a half- bridge switching mode converter consisting of saturated transformer is employed, the step-up transformer, current-limiting resistor and trigger circuit which were involved in the previous circuit are no longer used in the new circuit. The volume and weight of the new circuit are obviously reduced while the efficiency is enhanced. The practical operation shows that this circuit is stable and reliable.

We report the fabrication and operation of an optically addressed spatial light modulator(OASLM), consisting of a hydrogenated amorphous silicon (α-Si: H) pin photodiode as a photosensor and a twist nematic liquid crystal(TNLC) as the modulating material. The intrinsic and doped α-Si: H films are deposited continuously by pECVD method in a reaction chamber with a shutter. The optical measurement indicates that the OASLM has a resolution of at least 20 lp/mm. The contrast ratio under the 300 lux illumination of white light is higher than 25:1. The white light writing sensitivity is about 3 lux.

A new technique of using auxiliary-mirror holography to analyse 3D vibration is proposed. The intensity distribution of the auxiliary-mirror time-averaged holographic interferogram is discussed. The solution in which the above holographic technique is used to measure the 3D amplitude and the method which draws information of the virtual point sources of the refcrence beaxns with the help of quasi-same-position auxiliary-object holography are explained. The problem of the position of the zero order bright fringe of the auxiliary-mirror time-averaged holographic interferogram is analysed in theory.

The enhancement processing is performed by using a photorefractive crystal Cu:KNSBN placed on the Fourier transform plane of a coherent system under,cettain conditions. A Leplacian operator is formed on the transform plane because of the phase conjugation effect inside the crystal. Experimental result and a brief theoretical analysis are presented.

pumped by a home-made diode-laser, Q-switching and single-axial mode prelasing Q-switching are achieved. For lower pumped power, optical-to-optical transverse effjency and slop efficiency are 2. 4% and 15% respectively when the output is TEM00 mode. Comparison is made to the LD pumped Nd: YAG laser.

Based on the physics fact, an extra equation has been introduced to specify the wavelength of the two-segment abeorptive bistable semiconductor lasers(TABLs). With appropriate modifications, conventional rate equations have been used to study the wavelength characteristics of the TABL. Calculations lead to a wavelength loop accompanying the hysteresis process, indicating a wavelength jump towards the longer wavelength at "switch-on" (sudden increase of output power) and a reverse process at "switch-off" (sudden decrease of output power) as shown in Fig.1 and Fig.2.

Experiments on CW and self-mode-locked Ti: sapphire lasers are conducted with the crystals produced in Shanghai Institute of Optics and Fine Mechanics, Academia Sinica(SIOFMAS). According to the results, the quality of the crystals are assessed.

In this paper the influence of the pump beam mode on the efficiency and beam mode of a CW Ti: sapphire laser is discussed. The results have been compered with experiments.

Using DC-pBH laser diode(LD), the broadband LD module of practicable package type is developed. The LD module is studied and measured on the packaged LD model, involving small signal modulation characteristics and nonlinear distortion. Its 3 dB bandwidth of optical resonance is more than 2GHz. This device is able to satisfy the bandwidth need of 2. 488 Gb/s in the optical fiber communication system and be used in the GHz microwave subcarrier multiplex optical fiber communication system.

The effects of group-velocity dispersion in SHG crystal on the evolution of optical pulses in a mode-locked laser by a nonlinear mirror were analyzed. According to theoretic results, we have simulated the experiment in Ref. [5], the theoretic results were correspondent with the experimental results.

Characters of dispersion and absorption in a V-type atom system interacting with a coherent coupling field are investigsted. The real and imaginary parts of the polarization are calculated by density matrix equations when atomic coherence between the two lower levels occurs. The influence of different coupling field intensities as well as various rates of incoherent pumping on atomic absorption and dispersion is also considered.

The simulation of the nonlinear effects of laser atmospheric propagation is reported in this paper. A set of atmospheric hydrodynamics equations and nonlinear electromagnetic wave equation which interacts the atmosphere are given. The wave equation describing the stimulated thermal Rayleigh Scattering(STRS) induced small perturbation instability is derived. And turbulence is theoretically treated. Basing on thais equations, we per formed a set of 4D programs(TURBLM) to simulate thermal blooming and phase compensation for it, small perturbation instability, and the interation of turbulence with thermal blooming. The simulated results accord with theories and experiments.

In this paper, we prove that the order of a supergaussian beam has a upper limit, drive the analytic expression of the upper limit, and discuss some impbttant characters of the supergaussian beams.

A theory is proposed for the limited length nonlinear weakly-guiding waveguide.An explicit expression is obtained for the field distribution.

In this peper, we prove that, for any stable propagnting light beam in vacuum or in the symmetrically parexial ADCD system, the z components of beam cross-section angular momentum and angular momentum square are both.invariables which are independent of the position of the cross-section. Furthermore, we still discuss some characters of light beam which are relative to angular momentum.

In this paper we report the experimental results of controlling CuBr laser modes by using an injection seeding technique. We have amplified the single longitudinal mode CuBr laser pulses and obtained the narrowing-linewidth copper laser radiation with an average power of more than 100 mW. Theoretically, we have analysed the injection seeding process in short-pulse high-gain lasers and discussed the experimental results in the injection seeded CuBr laser.

The effects of melting temperature and chemical reaction agents(CCl4, SOCl2 and pOCl3) on removal rates of OH group in BaO-p2O5 and R2O-BaO-p2O5 system phosphate arser Glasses are investigated. Relationship between the content of OH group and the fluorescence lifetime of Nd3+ in these glasses is discuased. Moreover, laser properties and physical properties of these glasses before and after OH group is removed by RAp method are compared.

Considering the change of the grating modulation index, a united analytic formula of the response time for two-beam coupling is obtained by solving the dynamic equation of two-beam coupling. It involves paratmeters of crystals, incident intensity, full incident angle and signal-pump ratio. The experimental resultS using Ce:KNSBN crystal are in good agreement with the theory qualitatively.