In this article, Lorentz equation and energy equation for the relativistic electrons are solved order by order on the basis of the single-electron model. The gain expression for free-electron lasers with gradient magnetic field is obtained. The result show that when the amplitude of the periodic magnetic field varies along z direction, the gain is expected to be increased.

With a phase grating located at Fourier frequency plane, optical image subtraction is obtained as a result of the coherent superposition of the zeroth and the first order of the diffracted light. Compared with the amplitude grating method, it makes more use of the processing lenses’ aperture. If a suitable phase grating is adopted, image subtraction and addition can be simultaneously realized. The experimental result is given.

The transient optogalvanio signals (OGS) corresponding to the transitions from IS to 2P states of Ne within a hollow cathode discharge tube under various discharge currents were tested. The most interesting phenomenon was that, when the current was small enough, the mirror imaging symmetry between the profiles of 1S2~2Pk transition and of 1S4(i=3, 4, 5) -2Pktransitions disappeared. The theoretical analys is based,on the three states model and a hypothesis of the relaxation process of cathode bombarding is presented. It agrees with the experimental results.

Opto-galvanic effect in the He-Cd+ hollow cathode discharge tube was experimentally studied. The dependence of the opto-galvanic signal (OGS) on the laser power, the discharge current and the position along the laser tube are presented. The possible mechanisms of OGS are discussed. It is found that OGS could be used in measuring the homogeneity and stability of the Cd+ concentration along the laser tube.

The external quantum efficiency of the lasers with two sections in a common cavity was derived. Relation between the external quantum efficiency and the current density of GaAs-Al0.3Ga0.7 As DH lasers with two sections in a common cavity was calculated. The external quantum efficiency for the above laser has been measured and the, experimental results are in agreement with the theoretical analysis.

We have proposed and developed an integrated surface multi-junction MOM (metal-oxide-metal). After being treated by a special electro-forming process, light emission from MOM at room temperature has been observed. The I-V characteristic curve of MOM presents a negative resistance feature at low atmospheric pressure., and a memory effect in air. When multi-junction MOM interacts with a laser or a microwave beam, it shows good performances in producing fast responsie signals. The device has the potential application of producing electro-magnetic oscillation in the region from microwave to light.

The experiment of three beams interference is realized using three faceted holographic lens. The experimental result agrees with the theoretical analysis.

We have systematically analysed the duration of laser pulse generated by using intracavity self-injection for various cavity arrangements. With the ferrite transmission line technique a driver of high voltage pulse with continuously tunable duration was constructed. A particularly designed avalanche circuit drives the Pockels cell PC1 to perform both Q-switeh-ing and cavity dumping. Only changing the voltage pulse duration but not the cavity arrangement, a 3 MW single laser pulse output continuously and conveniently tunable from 1.3 nsec to 6 nsec was obtained form a Q-switched phosphate Nd: glass laser.

A method for measuring the refractive index profile of selfoc rod lenses using the holographic interference microscopy is presented. Principle of method, measurement results and error analysis are given. It has the advantages of high accuracy, wide field of view, simple data processing and continuous variable magnification.

The of grating sampling method have been successfully used in the ultrahigh speed photographic experiments. Since the method has the advantage of efficient and continuous samp ling, the ultrahigh speed photography is expected to have practical application as picosecond oscilloscope.

Six infrared absorption bands caused by Jwater in phosphate glasses were identified. The relationship between the absorption coefficient at 3.47m due to water and fluorescence lifetime of Nd3+ weve determined. The variation of water contents during melting was measured in detail and the result showed that it increased obviously after stopping dry gas bubbling. The BAP has been used to remove the water in phosphate laser glass and it is easy to fabricate a glass with K3.47μmOH=1.

In this paper, basic theory on the measurement of refractive index n, absorption coefficient k and thickness d of absorbing thin films using a phase-modulated laser interferometer is presented. Relationships between n, k, d and the measured parameters P, Q, are introduced. The exprimental methods determining P, Q, and & as well as their self-correction are given. The evaluation of the phase difference is discussed in detail, also discussed is the experimental investigation of correctoin factor F.Three types of thin films (one weakly absorbing film and two absorbing films) are studied. The results are compared with those measured by an ellipsometer.

Eelative measurement of spectrum scattering is used in general. This paper presents a method which can be used to measure the absolute spectrum scattering.

A new circuit for CW laser power supply with three-phase Flotrol is presented. The output current can be adjusted continuously from 5 to 40 ampere, and the current stability is up to 10-3. It has the advantages of simple structure, stable operation and easy adjustment and maintenance.

A clinical report is given on 28 cases of female urethral polypus satisfactorily cured by a Nd glass laser. Its curative effect is better than the conventional methods.

80 casese of herpes simplex infection in labialorris have been treated by a He-Ne laser and satisfactory curative effects obtained.

35 cases of children’s enteritis have been treated with low power He-Ne laser irradiation of acupoints and obvious curative effect observed. The possible mechanism is discussed.

From the end of 1978 to February 1984, during the winter season, 30 eases of chilblain were treated usinga model 741 low power He-Ne laser.