The kinetics of generating picesecond light pulses by gain modulation of semiconductor laser is analysed based on nonlinear rate-equations. Special double avalanche pulse generators are designed to produce short injection-current pulses. The optical pulse of 15 ps (FWHM) is obtained by gain modulation of unbised InGaAsP lasers.

The reflection characteristics in total-internal-reflection waveguide optical switch are analysed in deteil. It is shown for the first time that there exists the phase changes of reflective modes and their relative phase difference. The results of numerical calculation indicate that the power reflectivity, reflective loss, phase change and their relative phase difference for the reflective TE mode and reflective TM mode remarkably depend on the refractive index change, the loss in switch region and the propagation angle.

A new design of polarization prism system is described, which has many advantages, including low loss, high isolation, compact construction and convenient adjustment. Its loss and isolation are 0.6 dB and 24 dB respectively. By using this system, it was experimentally confirmed that the insertion loss, including fiber connection loss and the isolation of the circulator at 1.3 μm are 2.2～2.4 dB and 20.5～23.1 dB, respectively.

The quantum noise spectrum in demodulating optical PSK signal by delay line is presented. The effects of bit rate and detection condition on the quantum noise are discussed.

This grating interferometer uses grating as beam splitter, and behind the grating two beams interfere with each other. It can be used to observe phase objects, and the interference fringes can be modulated on the continuously changed phase objects for measurement.

We suggest a Moire deflectometry for measuring the object with synchronous change of phase, displacement- Moire deflectometry. When the object is rotating or wiggling, the displacement of Moire fringe indicates the angle of axis, and the stability of fringe indicates coincidence of the beam axis. This method is simple and the automeasurment is easy with high accuracy. In this paper the theory, measuring accuracy and some applications of this method are introduced.

A high power square wave power supply consisting of fast and high power SCR for pulsed lasers is developed. The pulse width and amplitute can be continuously varied from 0. 5 ms to CW and from more than 10 A to 300 A, respectively. Its current anti-voltage, realiability are better than those of the power supplies consisting of GTR. The operation principle and experimental results are described and the design formula is derived.

A serial electrode system is proposed for radio frequency (RF) excited fast axial flow CO2 lasers. The way to get uniform RF voltage along the electrode is analysed. The design procedure and its frequency loading characteristics are given.

We have measured plasma spraying ceramic coating and laser remelting of plasma spraying ceramic coating to metal surface cohesive strength with acoustic emission technique. The acoustic emission porperty. for laser remelting of plasma spraying ceramic coating have been discussed, and the process to preduce cracks for laser remelting of plasma spraying ceramic coating were also studied.

Using a continuous wave Ar+ laser and a thermoplastic holographic camera, double-exposure holograms were taken of a human eyes in vivo. Exposure-times, 2×0.25 ms, interval 2×2.5 ms and 2×0.5 ms, interval 5 ms were obtained by combining a shutter and a special light chopper. Light energy incident on the human retina was only 0. 4mJ/cm2.

A novel compound resonator——a confocal unstable resonator with large aperture coupling which can be applied to the high power lasers is presented in this paper. Design of the resonator is analysed in detail and method of design is provided. The laser modes of the resonator are studied both theoretically and experimentally. The theoretical results coincide with the experimental results. The output power is 0.75 kW with an efficiency of 8.0%, and the divergent angle in the far field is 1.73 mrad.

Dynamic study on sideband instability in a planar free electron laser has been conducted, and the method dealing with sideband instabilities in planar and free electron lasers are presented. Also explained are the characteristics of sideband instability in planar free electron lasers.

In this paper, we discuss the high order squeezing characteristics of the optical field which involves vacuum state, one-photon state and n -photon state.

Nonlinear modulation of optical intensity is realized in BSO crystal using electro-optical effect and photo conductive effect. The nonlinear transmission similar to the saturated absorption is obtained with a Ar+ laser of 25 mW.

Self-pumped phase conjugation in a-face titled-cut Ce-doped (KNa)0.1(Sr0.75Ba0.25)0.9Nb2O6 crystal was demonstrated without external reflection mirrors, pumping beam and applied field, and phase conjugation reflectivities as high as 25% were measured. The threshold power was lower than 0.03 W/cm2. Its photorefractive coupling constant was computed for various a-face titled-cut angles for the first time.

Intensity parameters Ωλ of Ho3+ in noncrystalline HoP5O14 were calculated with absorption spectrum measurement. Based on these Ωλ values, the oscillator strength, spontaneous radiative rate, branching ratio and integrated emission cross section were estimated. A discussion on the potentiality of application in the infrared laser material is given.