Amorphous Si-Nx:H films with low hydrogen contenthave been deposited using a CO2 laser assisted PECVD, or LAPECVD system. Inthis system, thin Si-Nx:H films were grown under conventional capacitive RF (13.56 MHz)discharge, with a CO2 laser beam hitting on a part of the substratesimultaneously. Either the substrates were resistively heated or not, these films wereproved to have larger index of refraction and better surface flatness. Besides, theirresistance to corrosion was considerably improved as compared to films grown underconventional PECVD process. While the resistive heating was replaced by appropriate CO2laser irradiation, the absorption of laser beam raised the substrate-thin film temperatureup to 55℃ only, andthe irradiation of laser beam reduced effectively the amount of hydrogen bond in thefilms. This non-thermic process proved that laser light at 10.58 μm wavelength gave more satisfactory results than at 9.52 μm, possible reason of thisobservation is postulated in this paper.

The adaptability of thediffractive optical elements fabricated by continuous technology in the practical systemis studied. The effects of the nonideal incident wave, uncoaxial system and allocation offocal plane on the uniform illumination have been simulated. The result shows that thiskind of DOE has huge adaptability, and some helpful parameters have been provided for testof engineering.

Displacement measurementerror and its character of self-mixing interferometer are analyzed. The design ruler ofself-mixing interferometer is presented. The system stability and measurement resolutionare experimentally studied, and the method for improving system stability and measurementresolution is given.

A hollow light guideusing the aluminum-phosphor bronze reflector to transmit UV laser beams has been studied.The delivery characteristics of the hollow light guide with different bending angle havebeen studied using XeCl excimer laser. The transmission of straight light guide was 72%/mand the transmission of bending wave guide of different radius of curvature have also beenmeasured. The measurement showed that the transmission was proportional inversely to thebending radius R. Some methods to improve the transmission have been proposed. Theexperiment showed that helium gas displayed the weakest absorption and can improve thetransmittance of hollow light guide. When the light beams with very small divergencepropagate as whispering gallery modes, which propagate through the guide by successivereflections from the outer wall only , the transmission is independent of the curvature R.

The effective trappingforce is defined and the effective force of a ring beam trap is calculated in the rayoptics regime. A comparison of the effective trapping forces is also given using solidbeam and ring beam. It is shown that the ring-beam gradient laser trap has a highereffective trapping force than the solid-beam laser trap and the stability of the ring-beamlaser trap is improved greatly too. Also the thermal damage of the ring-beam laser trap isreduced.

The introduction ofinsect-resistant δ-endotoxingene from Bacillus thuringiensis into Brassica napus was carried out by laser microbeampuncture. The acquisition of transgenic plants and the inheritance of transgene in T1generation were confirmed by PCR and PCR Southern blot hybridization. The bioassay oftransgenic plants showed that some of the plants exhibited tolerant to pest insects andinsect-resistance was maintained in the T1 generation. These results showed that theinsect-resistance gene was integrated into the genome of Brassica napus and was stablyinherited.

By using the binaryphase Gabor micro-lenses array elements in an information processing setup, a multipleimages are produced after several times Fourier transformations. Results show that thismethod is feasible and the produced multiple images are clear.

A new method of makingphase mask in LiNbO3:Fecrystal by photorefractive effect was demonstrated. This kind of phase masks are visual.It is a real-time and simple method that can be used to make many kinds of complex phasemasks in integrated optics and optical information process.

In this paper, thetechnology of fixing and developing of thermal fixing of holograms in photorefractiveLiNbO3 crystals is described in detail. The dependence of the peak diffractionefficiency of grating on the temperature was measured at fixing stage. The experimentalresults of developing show that developing by reference beam usually suffer fromself-enhancement, Bragg-angle shift, selective angel broadening and scattering noiseincreasing. Developing by incoherent light can avoid these disadvantages. In this paper, amethod of decreasing coherent degree of light is proposed for developing by originalrecording optical set-up.

This paper described apolarization detection method to compress the lager dynamic range of laser returnedsignals in airborne laser bathymetry system. The experimental results show that the methodcan compress the dynamic range of returned signals more than one order, restrain the laserbackscattering largely, and haven′t influence too much on detecting laser returned signals from theunderwater.

In this paper, a new CNCmodel called “conicalpeeling” is proposed.An adaptative control system and a Nd-YAG laser processing-machine have been developed.With this way, a tapered millipore (φ≤0.005 mm) has been made on natural diamond.

The software used tosimulate temperature and velocity fields in laser surface remelting process is developedon the basis of PHOENICS code. Computational methods ,which include a fixed-grid andgeneral source term based on dealing with melting and solidification, are employed.Momentum and energy changes caused by moving heat source are taken as additional sourcesin controled-equations, and the equations are discretived and solved using acontrol-volume-based method. By using the software, numerical calculationon heat transfer,phase change and fluid flow in laser remelting process of an aluminum alloy speciman arecarried out.

“In-situ” weld-alloying/laser beam weldingis utilized to join SiCp/6061Al MMC with titanium as alloying element. Microstructure ofthe weld is characterized as functions of alloying content and laser processingparameters. Results show that the needle-like harmful phase Al4C3 iscompletely eliminated and a novel composite reinforced by TiC and Ti5Si3is produced in the weld of SiCp/6061Al MMC by “in-situ” weld-alloying/laser beam welding with titanium as the alloyingelement. “In-situ” weld-alloying/laser beam weldingis a new promising method for joining of SiCp/6061Al MMCs.

By using Cr4+:YAG as a saturable absorber, ahigh energy and high stability Q-switched pulse with a single pulse energy >85 mJ,pulse-width of 40 ns and energy fluctuation of 0.4% was obtained in an unstable resonatorNd:YAG laser with ananti-resonant ring (ARR) structure. The experiments on plane-convex unstable resonator andplane-plane critical resonator were also tested for comparison and the results wereanalyzed.

A LD pumped highefficient intracavity second frequency generation Nd:YAG laser is reported in this paper. The frequency of thehigh repetition Q-switched laser is up to 10 kHz. The laser average output power of 2.1 Wat 532 nm and 2.6 W at 1.064 μm are obtained with 12 W LD pumping power. The optical-opticalconversion efficiencies are 21.7% and 17.5% respectively.

The high-power and thehigh-efficiency green laser output was obtained in an AOQ switch straight cavity Nd:YAG laser. The high-pure KTP wasplaced in a temperature controlling stove and tuned by the temperature. The highest greenlaser output power was more than 38W. The conversion efficiency of the input electricpower to the green laser output power was 0.91%. The unstable degree was ±2.3%. Thefrequency doubling efficiency for the high-pure KTP was improved by 18.8% compared withthat for the conventional KTP.

The reconstructingprocess of the branch lines of a continuous wave CO2 laser is observedexperimentally with the help of a FMCW laser radar system. It is considered that thebranch line is stabilized when the heterodyne signal of a far-field target appears. It isconcluded that different branch line takes different time to reach its stability, and thetypical time is about 20 μs. Especially, the end of the competition between branch linesdoesn′t mean thecoherence reaching its best situation. The observation shows that it takes at least 6 μs to reconstruct the coherence ofa branch line.

A new laser crystalLiTaO3:Cr3+ is pumped by a giant pulse at 660 nm, and the outputenergy of 1 mJ of giant laser is obtained at 901.6 nm. Using BBO crystal to double thefrequency, the blue-green laser output at 450.8 nm is gained.

By means ofmulti-reflectivity-peak fiber gratings, 4-wavelength, 8-wavelength lasing with wavelengthspacing of 1.6 nm or 0.8 nm and linewidth of 0.01 nm have been obtained in the experimentof σ-figure cavityfiber lasers.

Functions of nozzles andproblems existing in designing wall geometry of single nozzle are simply demostrated. Anew method to design nozzle has been given based on the aerodynamic theory. The equationscontrolling nozzle flow in DF/HF chemical lasers, initial boundary conditions and aCompressible Scaling Method (CSM) used to simulate the nozzle flow have been introduced.

Two dimensional flowfields in different nozzles, with equal section throat area and different section lengthhave been simulated. The change of sonic line with the section length, and optimum lengthof the section have been given. The flow fields and the performance of three nozzlesdesigned with different methods, have been simulated and analysed. Results of simulationshow that the new method can optimize/promote the performance of nozzle, such as lateralvelocity, the efficiency of “freezing” fluorine atom and longitudinal velocity, and also can preventboundary layer separation and shock wave. Moreover, thickness of boundary layer has beencalculated according to the velocity field obtained from simulation. Developing tendencyof boundary layer in the nozzle of DF/HF chemical laser has been discussed.

The numericalsimulations of the model of double aluminum foils driven by high power laser beams arepresented. The state of flyer and the character of shock wave of target are depicted indetail, and the effects of several parameters on the state of flyer and the character ofshock wave of target are analyzed. The analyses of the simulated results showed that witha good matching between the target and laser, with a properly choicing the thickness ofthree-step target, the absolute measurement of equation of state may be approach.

Aiming at the powerequalization in all-optical networks, an optical configuration of two-stage Erbium dopedfiber optical power limiting amplifiers with incorporated differential loss loop ispresented. The effects on the dynamic range and noise characteristic by the loss value andrelative position were investigated theoretically and experimentally. The optimum valuesare around 60% for the position and 5～8 dB for the loss, respectively. Accordingly, an optical powerlimiting EDFA with a large dynamic range (over 20 dB under 30 mW pump power) isdemonstrated. The average output power within the dynamic range at the signal wavelengthof 1553 nm is in excess of 290 μW.

A novel all-opticalscheme for extracting clock pulses with basic frequency from the receiving non-uniformOTDM optical signal is proposed. The key point is: in the OTDM signal, the space betweentwo pulses is made unequally by artificial means. At the receiver side the base-frequencypulses can be otbained when such signal injects into a mode-locked fiber laser. Thefeasibility of this scheme is proved by experiment.

A newly designed highpower broadband source is reported in this paper. A 1480 nm laser is employed to pump theerbium-doped fiber. The light is reflected by a linearly chirped fiber Bragg grating, thusamplified two times. The output power achieved is 1.41 mW with a 10 nm bandwidth. Theworking current corresponding to the linearly output is from 375 mA to 645 mA.

The photoabsoptioninduced disordering (PAID) on lattice matched InGaAsP quaternary quantum wells isinvestigated using cw 1064 nm Nd:YAG laser. Quantum wells intermixing (QWI) is demonstrated byphotoluminescent (PL) spectrum. The process time could be reduced by heating the sample inadvance or focusing the laser beam. Two peaks of PL show that PAID technique could be usedfor processing the quantum wells locally on the wafer.