It is the key of absolute distance interferometry to establish a synthetic-wave measuring chain. This paper gives a general formula of synthetic-wavelength and a conventional measuring equation set for each stage of synthetic wave, and introduces two-stage synthetic hierarchy produced by 3.3922um and3.3912um dual-line He-Ne laser, as well as the related experimental results. On the basis of the hieraehy, this paper puts forward two interference measuring approaches. The discussion and analysis show that these two interfering system can be suitable to measurement of distance ranging from several meters to 100 meters, with an accuracy better than 1×(10-6~10-7).

We report here the generation of width-variable electrical pulses with suban-nosecond rise and fall time by means of two picosecond light pulses with a variable delay between them to drive two photo-conductive switches one after the other.

A composite'plate compensator, special composite retardation plate,is giver. By changing the vibration azimuth of entrance linear polarized light, the retardation of the compensator can also be changed with easy adjustment and high precision.

This paper reports three dimensional measurement of pulse laser field profiles by matrix CCD and the automatic test results are given by combining the matrix GCD camera with graphic processor, computer and printer.

The soft X-ray multilayer is usually composed of alternative materials of high and low atomic number. The optimum design of thickness for periodic quasiperiodic and non-perdic Al/Mo soft X-ray multilayers and the effects of roughness of surface, permeating of interface and thickness error on the reflectance of X-ray multilayer are discussed.

This paper presents a, new method of optical second order differentiation by lensless Fourier transform hologram. Theoretical analysis and experiemental results are given.

An all solid-state possively mode-locked Nd: YAG laser with a 400 um, (100) oriented GaAs component is reported for the first time and mode locked pulses with a duration of 16 ps, average energy of 10uJ were obtained with a probability of 90%.

This paper discusses thermal profile in a finite laser slab. Expressions of the temperature distribution are given under different pumping and cooling conditions. Computemzed calculations are carried out to give detailed explanation.

18.1ps optical pulses were obtained from a 1.3 μm InGaAsP laser at 1 GHz repetition rate by a multimode fiber extended resonator and the experimental results are discussed.

A novel two-dimensional surface emitting semiconductor laser arrays in quasi-continuous wave operating over 250mW at room temperature has been developed.

On the basis of analysis and contrast for the stimulated emission cross section the fluorescent lifetime and optomechanical coefficient as well as the ability to resist the thermal stress, it is shown that similar to the Kd: Y3A15O12 crystal the Nd: YAlO3crystal is a useful material to develop high power CW solid state lasers. 424W output power with an overall efficiency of 2.54% and a slope efficiency of 3.77% have been achieved from a 7 X155mm Nd:YABO3 rod.

The expressions of extraction efficiency are deduced by means of ponderomo-tive potential, the actions of tapeied wiggler technique on efficiency enhancement lasers are analysed, and the experiment of FEL with tapered wiggler intensity of magnetic field has been conducted by this technique, the result indicates that itsefficiency is 2.6 times that of FEL with constant wiggler intensity of magnetic field.

The radiator is an essential component in high power lasers. Researches show that the radiator made up of elliptical tubes with fins is the most suitable type among the existing multitudinous radiators. In accordance with the performance characteristics of the laser, the author also explains the design procedure of this new radiator.

A simple model of interaction of two-frequency laser with atoms is presented in this paper. The opto-electron spectrum produced in this model is calculated and the structure of photo-electron peaks are analysed.

The experimental set-up of time resolved, differential absorption used to mreasure the excited triplet absorption spectrum of dimerio chlorophyll α and the experimental results are reported. The peak absorption of the excited triplet of T1(4) and T1(D)are at 462nm and 466nrn,and the subsidiary maxima at 510 nm and 526 nm, respectively. The triplet lifetime of T1(A), T1(D), measured with a time-resolved double-beam method,is A/T=9.8+0.5,us and D/T=80+4us, respectively.

The Eaman spectra of KBr:Pb2+ single crystal after long X-ray irradiation at liquid nitrogen temperature are reported. The five new Eaman peaks are assigned to the local vibrations of the color centers induced by X-ray irradiation.

This paper presents a special out and an optimum experimental configuration for KNbO3:Fe photorefractive crystals. For the first time, a self-pumped phase conjugation using total internal reflection at room temperature is obtained, whose reflectivity is up to -60%.

The phenomena of acoustic emission in LN:Fe crystals nave been observed during the process of light induced quasi-breakdown. It is found that the super high frequency acoustic signal has been modulated by the low frequency acoustic wave which was introduced into the crystals, the frequency of which increases with the increasing of intensity of incident light and the period of the breakdown is the same as the jump one of the photovoltaic current and the light induced change of refractive index. It is caused by the strain effect of crystal induced from jumped space change field.

Hyperflne structure spectra of Eb D2 lines are recorded by means of laser diode as light source and the comparison with the calculated resuels is made.

The one photon absorption of slow electron colliding with positroninm in a laser field has been examined and the accurate variational scattsring phase shifts have been used to calculate the free-free absorption cross section.