The optical controlling reflection and the optical limiting effect realized in ZnS/ZnSe nonlinear stratified waveguide grating is reported in this paper, and the deflective angle of the second order Bragg diffraction was about -2° and the change of refractive index was about -0.049 at Ar+ laser optical intensity of 2.60×105 W/cm2. The refractive index coefficient of the material obtained was -1.9×10-7 cm2/W, which accords with the value reported by the foreigner. The nonlinear threshold of the optical limiting was about 140 mW, the limiting amplitude threshold was 24 mW.

Using computer aided designing and self-matching of coating system to compress the pass-band corrugation, large size film polarizer series with good qualities in a wide spectral range were developed to satisfy requirements for very high power laser. HfO2 and SiO2 were used as the material of the film. The work-angle of these multilayer film polarizers is 60° and the work-wavelength is 1053 nm. Some testing experiments and laser induced damage experiments were done to testify the optical performance and the damage thresholds of the film polarizers.

The study on the third continuum of argon pumped by the relativistic electron beam was made. The small signal gain of the continuum was measured with the mirror. According to the experimental setup and method, an accurate mathematical model for close range detection is built up. With numerical simulation, the small signal gain of the third continuum is obtained.

A new type matching filter by computer-generated hologram is presented in this paper. The filter is obtained by adding quadratic phase factors into conjugate frequency spectrum of object, then encoding and reducing. Because of the filter having function of self-focusing the optical configuration becomes more simple, more compact, and easier to adjust. It is suitable for objects with different scale. The experimental results are consistent with theoretic analysis provided.

A new type of autocorrelator with a rotating retroreflector is reported. Optical path length alteration is produced by introducing a rotating retroreflector into one arm of autocorrelator. It can be used to realize the real-time monitoring and measurement of femtosecond laser pulses. The conception of error compensation is introduced in autocorrelation measurement, and the interferential correlation curve is corrected with a computer.

The precision target positioning system applied in target chamber of high power laser facility is studied. The system utilizes digital speckle correlation method (DSC) and has theoretical precision 0.01 pixel and the position error under 8 μm. In cooperation with computer-control-step-motor, the positioning system has such advantages as automatization, high precision, large view field and non-contact etc.

The contrast of the polarization image was measured to be 4.1 and the imaging range was 1.5 m. According to the formula expressing the relation between the contrast for polarization image and the attenuation of water, the farest imaging range with polarization was calculated as 1.92 m.

The location of a hidden object in multiple-scattering media was studied using the mean intensity of backscattering light. The location of the hidden object was restored with the intensity distribution at different positions by scanning the sample. The intensity distribution was experimentally studied when the object hid at different depth in multiple-scattering media.

On the basis of introduction to the hologram record and reconstruction, the analysis of particle hologram is carried out for the bubble fields of foam-devolatilzation (foam-DV) in cyclohexane/PDMS system. The effects of the operating vacuum, the initial cyclohexane concentration and the liquid height on the number-average bubble sizes are discussed emphatically. The results show that the number-average bubble sizes increase linearly with increasing liquid height, the operating vacuum and the initial cyclohexane concentration, but the liquid height is a key factor. The factors affecting the measurement error are also discussed.

In this paper, the cyanine thin films and CD-R samples were prepared by the spin-coating process. The transmission, reflection and absorption spectra of the cyanine thin films were measured by the spectrophotometer and the reflection and the absorption of this cyanine thin film are high enough for optical recording at 780 nm. The reflection of multi-layers reached up to 75%. The results of the optimum recording power measurement indicate the optimum writing power is about 7 mW.

The Bragg-shift in reflection-type photorefractive holographic gratings, especially its time evolution, has been investigated both theoretically and experimentally. Experiments demonstrated that there does exist the Bragg-shift in reflection-type photorefractive holographic gratings, and it increases with time similarly to the time evolution of the index modulation. The research shows that in large-scale holographic storage, the influence of Bragg-shift on the reconstruction quality can be negligible so that the hologram can be read out at the same angle as it was recorded, if the hologram was recorded for a short exposure time.

A two-dimensional and quasi-stationary numerical model is presented to study the fluid flow and the heat transfer in high power density keyhole welding process. A recently developed method of the position-correction is employed to accurately identify the solid-liquid interface location during welding. A parametric analysis of the existing keyhole model is performed, and the effect of parameters such as material properties, welding speed, keyhole radius on the heat transfer is analyzed during keyhole welding process.

The detecting system of platinum inclusions in laser glass is reported. It is a scanning system controlled by a computer. The testing sample sizes: 600 mm×300 mm×40 mm. The scanning region: 600 mm×300 mm. Laser fluence is more than 20 J/cm2. The platinum inclusions are tested successfully. The sizes of platinum inclusions is less than 10 μm can be tested.

Fusion welding and butt welding of 6063 aluminum alloy (1～4 mm) and butt welding of LY12 aluminum alloy (1.5～4 mm) are realized by a home made 5 kW transverse-flow CO2 laser with 2～3 kW low order mode output and the welding speed ranged from 20 to 120 cm/min. The influence of processing parameters on weld quality are discussed.

The characteristics of instantaneous optical absorption in bacteriorhodopsin(BR) pumped by different wavelength cw and pulsed light were studied with the experimental system of “cw optical pump-probe+pulse laser pump” designed by ourselves.Especially, a 632.8 nm laser was used as the cw pump-probe light to study the correlation between the optic-absorption kinetic characteristics of BR’s every state during the optical cycle process of proton charge together with its instantaneous optical absorption and the intensity of cw pump-probe or pulsed pump laser.

An electrooptically Q-switched RF excited CO2 waveguide laser is presented. The waveguide length is 400 mm. The cw output power of 3.5 W has been achieved with the electrooptic crystal without pulse voltage, mounted within the waveguide. The Q-switched pulse repetition rate is 1 Hz～10 kHz. The peak power of 200 W and the pulse width of 400 ns have been obtained at the pulse repetition rate of 10 kHz.

A double-cladding Yb3+-doped silica fiber laser pumped by LD is reported. The laser outputs are obtained in several wavelengths. The laser output of 3.84 mW at 1037 nm was obtained with a pump threshold of 3.58 mW and a slope efficiency of 55%. The spatial profile of laser is single spatial mode.

A two-cell SBS phase-conjugating mirror pumped by pulsed Nd∶YAG laser was experimentally investigated. After returned to YAG amplifer and coupled out by a polariser, SBS output beam had the characteristics of duration tunability and good quality with near-diffraction-limited far-field divergence angle. The stability on SBS ouput energy and far-field divergence angle with the change of pump energy and separation between SBS generator and amplifier cells was also studied. By choosing pump energy, the fluctuation on SBS output energy and far-field divergence angle could be controlled within 5%.

A high-power high-efficiency Nd∶YVO4 solid-state laser end-pumped by a fiber-coupled diode laser was reported in this paper. 11 W of CW TEM00 mode output was obtained at a pump power of 20 W, giving an optical conversion efficiency of 55%; the output power reached 7.1 W at pump power of 12 W, resulting in an optical conversion efficiency of 59%, and a slope efficiency of 64%. The thermal focal length of the Nd∶YVO4 crystal was measured under various high pump power levels. The results show that thermal lensing within low-concentration Nd3+- doped high-quality Nd∶YVO4 crystals is relatively quite weak, provided that the laser crystal is efficiently cooled.

The physical meaning of complex Fresnel number is discussed in detail based on the axial intensity of Gaussian beam diffracted by a hard aperture. The far-field intensity on axis can be enhanced by several times of the original Gaussian beam using a suitable phase aperture. In the meantime, the central spot is smaller than the original Gaussian beam. An application example of laser collimation is given.

A gas mixture of krypton with a hot vapor of lithium was excited to obtain two diffuse vacuum-ultraviolet emission bands centered at 147 and 149 nm. The observed emission bands are assigned to the 21Σ+→11Σ+ and 11Π→11Σ+ transitions of (KrLi)+ ionic excimer. A similar band with two peaks at 186 and 189 nm from electron-beam-pumped Xe/Li mixtures was believed to be the same transitions of (XeLi)+ excimer.