The modification of the physical model for the calculation of small signal gain by measuring spontaneous emission magnified with a mirror is done. The analytical expressions of small signal gain from the model modified are given. The coefficients of the small signal gain of a S 2 laser medium pumped by transverse fast discharge are obtained, and the maximum of g 0 is 0.082 cm -1 . And the results are analyzed and discussed.

The Acquisition, Tracking and Pointing (ATP) technology is one of the key technologies in the free space laser communications system. This paper analyzes the ATP theory, and obtained results from experiment. The key parameters of the experimental system are: (1) beacon divergence, 2α b=5 mrad; (2) receiver field of view, 2β ω=10 mrad; (3) angular coverage, 2α≥±1°, 2β≥±1°. The results of the experimental demonstration show that the system can work well in the distances of 1.6～5.0 km. The results accurately match the theoretical analysis.

An all optical gain clamped and flattened fiber amplifier is reported. This technique is applicable for WDM networks with dynamic gain equalization of high gain, high power EDFAs. The dynamic range reaches 23 dB (-40~-17 dBm) for a constant 33 dB gain, while the -1 dB gain bandwidth is 14 nm (1547~1561 nm). The output signal power is 16 dBm.

The binary amplitude modulated phase only spatial filter (BAMPOF) is studied and different filters are compared to access the BAMPOF′s performance. The study shows that the BAMPOF has good features regarding the sharpness of the correlation peak, Horner efficiency and noise tolerance. So, the applications of it in the optical pattern recognition is promising.

It is proposed that a segmant of an Er doped fiber with a couple of fiber gratings on the ends may be used as a novel optical bistability device with low power and high speed. Operation and bistability threshold of the device are analysed in accordance with the distributed feedback couple mode theory and the nonlinear characteristic of the Er doped fiber. It is shown that a nanoseconds microwatts bistable operation of a centimeters sized device is realizable under nowaday technological conditions.

A new method with a pre existent slit for making rainbow holograms is presented. This method not only can rise the energy utiliziation, but it can more easily gain rainbow holograms of a larger viewing angle.

In this paper, we proposed that virtual images, which have rotation, shear and inversion, can be obtained by a simple coordinate transformation of the Fourier spectrum in the Fourier computer generated Hologram. We clarify the principle of this coordinate transformation. The experimental results are in excellent agreement with a theoretical analysis.

We have analyzed numerical code modulation of semiconductor microcavity lasers by using rate equations. It is found that microcavity lasers have high speed pulse code response and minimum error probability. An excellent eye diagram can be obtained with the microcavity lasers modulated by a 50 Gbit/s current if their spontaneous emission factors equal 0.1. The lasers will open vast vistas in future optical connection. Furthermore, we have simulated fiber communication systems with microcavity lasers as the light sources 10 Gbit/s numerical codes modulated and have given the received eye diagrams sfter transmission of different distances. It is proved that the system can stand for 60 kilometers'transmission.

The principle of magneto optical storage is thermo magnetic recording. Data are recorded in media in the form of magnetic domains. The shape and thermal stability of magnetic domains are important to the storage properties of magneto optical disks. The experimental results of shape and thermal stability of magnetic domains are reported in this paper.

A “sample independence” restoration method aiming at deep layer attenuation correction of three dimensional confocal scanning images is given with the analysis of its mathematical models presented in details. A rapid access based on FFT is derived with the presumosition that the resulted images will be precise enough. The algorithm, without additional noise inducement, is also proved to be accurate, efficient and flexible. The computing efficiency and memory consumption are discussed followed by its computational realization. Approaches for better performance are proposed subsequently. The successful applications to both test images and real ones are also given.

A new holography optical scanning holography has been proposed, which is a hybrid optoelectrical processing technology. The principle of the optical scanning holography has been elaborated and the result of the numerical simulation is given.

A novel reflection scanning near field optical microscope(RSNOM) which uses a fiber probe as both the light source and detector was developed. By means of interference detecting and polarization beam splitting detecting, the RSNOM eliminated the background noise disturbance which is commonly encountered in this kind of SNOM, and a high optical signal/noise ratio was achieved. Moreover, by vertically vibrating the sample, the light signal was modulated and detected with a lock-in amplifier, and the light intensity gradient imaging of the sample surface was realized, which further improved the image quality.This research shows that the RSNOM could detect the evanescent near-field wave effectively, and the image with a super-diffraction-limit resolution was obtained.

A new metal sheets flexible forming technique——laser bending process has been numerically simulated by using the finite element method of large elastic plastic deformation. Relationship between the bending angle and geometry of sheets and technological parameters is discussed. It is shown that the calculated values are in good accordance with the experiments.

The investigation on the continuous wave, self Q-switched, self mode locked, and self Q-switched self mode locked operations of a Cr:LiSAF laser with a three mirror cavity and with low pump power from an argon ion laser at the 488 nm line are reported. Without any active modulator or saturable absorber in the cavity, 51 fs pulses at a repetition of 150 MHz and with an average output power of 48 mW for 860 mW pump power are obtained.

A nonlinear amplifying compound loop mirror (NACLM) constructed by two fiber couplers is presented and analyzed. The analysis shows that the nonlinear reflection characteristics of the NACLM can be adjusted by changing the splitting ratio of the optical fiber couplers. Using the NACLM and a bulk semiconductor saturable absorber, stable passive mode locking in an erbium doped fiber laser can be obtained. Passively mode locked pulses of a repetition rate of 248 MHz has been achieved. It is suggested that using a NACLM as a passive mode locking element, generation of ultrashort pulses of very high repetition rate is promising with a fiber laser.

In this paper the performance of a Cr 4+ :YAG passively Q-switched diode laser pumped QCW slab Nd:YAG laser with a repetition rate of 100 Hz is reported. The dependence of the pumping threshold, the pulse width, the average output power as well as the energy extraction efficiency of Q-switched pulses on input pump pulsewidth was observed. A pulse width (FWHM) of 37.4 ns of the Q switched laser was obtained. The laser system operated very stably.

A 1.3 μm InGaAsP/InP strained compensated multi quantum wells structure grown by low pressure metalorganic chemical vapor deposition (LP MOCVD) was proposed. The threshold currents of buried heterostructure (BH) MQW lasers with this strained layers structure were 4~6 mA mostly. The characteristic temperatures up to 67K were observed for the devices under a temperature between 20~40℃, the single facet slope efficiency is 0.3 mW/mA at room temperature.

A new phase unwrapping algorithm is presented. It is mainly used in the cases in which there are a few fringes and the quality of the fringes is relatively good, however, a failure of unwrapping is encountered only due to low modulation points and speckle points noises, or due to dusts. The algorithm is based on one dimension FFT. It is simple and easy to realize.

The non reaction dynamics of Ar+HF (ν′,J′)→ Ar+HF (ν″,J″) has been studied based on the analytical potential energy function of ArHF (X 1Σ +) using the quasiclassical Monte Carlo trajectory. It is reasonably found that the populations of rotational levels, particularly, for higher J values, are remarkably relaxed, however, it is not effective for the vibrational levels of HF.

The large range homogeneous field of a large scattering slit can be used to make marking′s large viewing rainbow hologram. Cutting the Gaussian field into two symmetrical light fields and overlapping them in a frosted glass, thereby the large range homogeneous field is obtained. The optical system using the general reflection devices is presented and analysed. The new optical setup can obtain more homogeneous brightness in the large-range field. The satisfactory experimental results have been obtained.