This paper reviews the past and present developments of optical parametric lasers and points out directions for investigation in the near future.

The survey of dual wavelength crystal lasers is introducted in this paper. Our research results on dual wavelength crystal lasers are described mainly.These are as follow: oscillation condition of a simultaneous multiple wavelength laser has been esta blished and used to analyze the possibility of simultaneous oscillation in various neodymiumhost crystals, such as Nd:YAG, Nd:YLF, Nd:BEL and Nd:YAlO3 (YAP)crystals at transitions from 4F3/2-4I11/2 and 4F3/2-4I13/2.It shown that this kind of laser can be realized in all the described crystals in a pulsed state. In general, continuous wave operation, however, can only be achieved in Nd:YAP crysta1. On the basis of these results. the CW dual wavelength crystal lasing has been achieved for the frist time by using Nd:YAP crystal. The output power of 1079.5 nm and 1341.4 nm was 23.9 W and 25.4 W respe ctively.The Nd:YAG and large energy Nd:YAP dual wavelength pulsed lasers were also acquired. The experimental results show that the temporal and spatial overlops of both beams were quite good for both lasers. In addition.we has obtained 1655 nm and 1663 nm dual wavelength and 27l1 nm, 2730 nm and 2795 nm three wavelength Er:YAP lasers.

The recent advances in semiconductor lasers are reviewed. It includes strained-layer quantum well lasers, vertical cavity surface emitting lasers, visible lasers, gain-coupled distributed feedback lasers and high power laser array

The structure, crystal growth, fabrication and characteristics of the vertical—cavity surface—emitting lasers (VCSEL) as well as their applica tions and prospects are reviewed in this paper.

In this paper, the recent developments and application perspective of high—power solid—smte slab lasers are reviewed. Based on our investigat~n results, some key problems and techniques concerning slab lasers, such as the thermal effects, pumping cavity and resonators, are analyzed physically.

Recently, interest in diode laser—pumped solid—state lasers (DPL) hasincreased due to their advantages over flashlamp— pumped solid—state lasers. This review summarizes the new progress of DPL and its potentialapplications on military, industry and meducube. We also give an overview of domestic investigations on DPL, includod insingle—longitudinal—mode, Q-switched and mode locked lasers pumped by CW-1 W and Quasi—CW 60W LDA.

In this paper, the recent progress of high pulse energy, high pulse power and average power excimer lasers are presented, their applications in scientific research, industry and medicine are also discussed.

The capability of coherent radiation from cluster and its ions at VUV／XUV wavelength has been reported. Typical structure of cluster, the principle of coherent rad iation of claster, methods of producing coherent rad iation of cluster and the current profess of the said studies are described.

In this paper, We sulnmarize the current technological develope ment and prospect of RF transversely excited diffusively cooled CO2 lasers, point out that the high beam quality, compact device size and high performance are the future development trend of high power CO2 lasers, and propose a volume scaling technique for obtaining high beam quality and compact high power CO2 laser.

This paper presents and reviews high power industrial CO2 laser of a new generation．The bxcitation of laser by high frequency, radio frequency and microwave have been obtained. The power density in discharge zone of these lasers is more than 30 W/cm. Therefor, these lasers with copm act construction and light weight ha s been realized． These lasers with stability and reliability can meet the requirements of industrial production more.

Basing on the performances of copper vapor laser, several remarkable problems related to design a master oscillator—power—amplifier chain have been briefly mentioned. The inaction source, the spatial filter, the delay and timing of amplifiers, thermal lens effects and the corn pensation, the polarization and so on are discussed.

Chemical laser is characteristically energized by an exoergic chemical reaction which produces the nece ssary population inversion of lasing species. Based on the enormous chemical energy deposit, several kinds of chemical laser now deliver the cw power outputs of megawatt magnitude, far higher than any other lasers. Accordingiy, along with theimprovem ent of gas medium homogeneity and mode-electivity of the optical cavity, chemical laser has also attained high bearu quality of a near diffraction limited divergence angle. Recent efforts in developing new chemical laser have focused on the short wavelength chemical laser system, e.g. from theearly DF (l=3.8 μm) and HF(λ=2.7 μm) to lateO2(1Δ)-I (λ=1.315 μm) and HF overtone transition laser (～1.35 μm). At present the community of chemical physics are much interested in the visible chemical laser which may be realized by stimulated emission of an electronic excited state.

The new progress of free electron lasers is introduced, and the new progress of our research group is presented.

The operation principle of a without inversion laser is introduced, A detailed review on the some existing theories, experimental methods and its application prospect is given.

In this paper we suggest a new type of optical conformal transformation by used combination of diffractive optical elements after analysing the limit of classical optical pattern transformation. It can establish the conformal transformation between any different patterns which be similar to the complex analysis in mathematics, and would potential apply to optical information process and optical computing.

In the past few years, the photorefractive effect has been observed in polymeric materials. Compared to inorganic materials, polymeric materials have larger electro—optical response, lower dielectric constant, and higher damage threshold, and are easier to be processed. They, therefore ,have brisht future in applications. In this paper, the methods of studylng photorefractive effect in polymers are described, and the theoretical and experimental results reported up to now are reviewed.

Two new approaches to chaos control are suggested and the proposal on chaos guidance is presented.

The new development of femtosecond laser pulse generation and amplification is discussed in this paper.

In this paper, the four developed periods for ultrafast lasers weve precented and their content, focus points were diseusded. The research interesting and developing direction for femtosecond laser were described. The new relative subjects, such as femtosecond laser physics, femtosecond laser chemistry, femtosecond optical soliton communication and femtosecond electronics, were reviewed.

In this paper the evolution of passive phase conjugate technique (i·e. self—pumped and mutually/pumped phase conjugation) is summarised.

In this paper, several aspect of medicine development that promoted by laser technology are described. Laser technology is the techno-basis of analytical cytology, laser promote moleelar biology development. X-laser will innovate in technology of stereomicrology. Laser technology has been became a inportant treatm ent for some difficult operation of clinicl medicine.