According to the changing rule of transverse intensity distribution of blending-mode laser beam,and two arbitrary measured transverse intensity distributions,the optical parameters of high power CO2 blending-mode laser beam are calculated by means of least squares method and iterative process.

A Dammann grating interferometer using transverse Zeeman laser as light resource is developed in this paper.It takes advantages of reducing the effect of thermal expansion.Drift of the air refraction index can be easily conquered due to equivalent beam length.It is an attractive configuration with resolution of 0.7 nm.The error caused by the depolarization effect of the grating is analyzed.Calibration experiment between this grating interferometer and a differential dual-frequency interferometer has been implemented.The experimental results show that the equal divisions of the grating pitch by 8 times via optical system and the nonlinearity error is no more than 25 nm when the grating pitch equals 20 μm.

In this paper,a new kind of all solid state semiconductor laser pump-probe source was presented which was based on the principle of gain switch.By the control of direct current (DC) and radio frequency (RF) current applied to the source,two train pulses were made which had the repeat frequency of 1 GHz,pulse width of 50 ps and the delay time between two train pulses of around 200 ps.

In this paper,the energy damage threshold (EDT) at various pulse widths from 10 ns to 10 ms for the KTP crystals by focusing Nd:YAG lasers with different spot sizes on the crystals was provided.With the help of previous data obtained by the other authors,the curves of the EDT from 1 ns to CW for the KTP are given.These results are useful for doubling Nd:YAG/KTP lasers in optimum nonlinear conversion at various pulse width.

A novel method of Linear Extension for designing the 3D profile at the end of the electrode is proposed.Using this method,an electrode based on Chang′s profile is designed for a TEA CO2 laser,where a satisfying uniform field distribution on the 3D surface is achieved.

A new method,named curvature compansation milling,is proposed to increase F/ of refractiave microlenses array (MLA).It is described as follows: in order to decrease curvature of MLA fabricated by the conventional method of photolithography/melting/ion beam milling,several new layers of photoresist are coated on MLA,then heated and consolidated,at last milled again.Scanning electron microscope (SEM) shows that microlens is gently spherical,and surface stylus measurement shows that F/ number and F′/ number of MLA,fabricated by the new method,is promoted to 31.62 and 35.88,respectively,compared with 1.00 and 4.00,hardly obtained by use of conventional way.And the filling factor is promoted from 64.3% to 78.5%.Using the new method,point spread funtions of MLAs are more ideal,and their image quality is improved.

A four elements fiber Bragg grating sensing arrays has been interrogated using a tunable Fabry-Perot filter acted as a wavelength scanner and an oscilloscope and a photodector to monitor the distribution of the transmitted intensity in time domain.The sensing signal can be demodulated by comparing the shifted and unshifted spectra and the results are in good agreement with the prospected values.The measured range of the sensing elements can be improved by choosing the gratings with larger reflectivity difference.

In this paper,a new adaptive binarization thresholding method with using the power spectrum of the reference image on optical joint correlator was proposed.The performance of the adaptive binarization thresholding method has been compared with that classical optical correlator in the areas of correlation peak to and SNR (signal to noise ratio).At last,the results of the analyzing in theory,the digital simulation in computer and experiment in optic are satisfied.

CO2 laser has been suggested to heat the LiNbO3 for locally thermal fixing photorefractive hologram.Here a heating model is theoretically analysed and the stable temperature fields for demonstration aim are obtained.Based on the analysis of the relation between the fixed space charge field amplitude Esc and the fixing temperature Tf,two parameters,the localization coefficient Ψ and the average space charge field amplitude Eavesc ,are defined to evaluate the fixed local photorefractive hologram by CO2 laser heating the LiNbO3.The same analysis can also be used when boundary conditions and laser beam profile are changed.

The particle count technology based on light scattering at different collecting angles is studied and a device is constructed.The experiments verify that this device can detect large particles as well as small particles in liquid media.

A method to measure thermal diffusivity of opaque materials by a laser photothermal radiometry technique is introduced in this paper.The thermal diffusivity can be found by fitting the amplitude and phase of the sample photothermal signal at different frequencies.The thermal diffusivity of one-way arranges complex material is measured by the method,and experimental results of diffusivities at arbitrary direction are given.

High-power CW diode-pumped Nd:YVO4/KTP green laser by acousto-optic Q-switching is reported here,when the incident power is 6.3 W and the pulse repetition rate is 25 kHz,an average output power of 1.76 W with single pulse width of 60 ns was achieved,giving an optical conversion efficiency of 27.9%.The peak power of 1.17 kW and the single pulse energy of 70.4 μJ have been observed.

A model of magnetically confined discharge carbon monoxide laser is presented in this paper.Electron energy distribution function and the influence of the magnetic field on electron impact excitation rates are discussed.The vibrational-state populations of CO molecules and small-signal gain with magnetic field are calculated.The electron density in the energy region corresponding to the maximum electron impact exitation cross sections of CO molecules increases greatly due to magnetic field being added.The electron impact excitation rates,the vibrational-state populations and the laser small-signal gain increase.

In this paper,the factors influencing the ultimate output power of laser diodes are analyzed.The GaAlAs/GaAs material with gradient refraction index,separate confinement single quantum well structure has been grown by MBE.The CW output power of the array diode laser is 10 W.The peak wavelength is 806～809 nm.

Measurements on the third order optical nonlinearities of the conjugated polymeric cast film of PPQ (polyphenylquinoxalines) were performed based on the so called Z-scan method using a frequency doubled mode-locked Nd:YAG laser with low repetition rate.The nonlinear absorptive coefficient β=0.59 cm/MW,was obtained for PPQ,in addition,the measured nonlinear refractive index coefficient γ=2.4×10-12 cm2/W was in a good agreement with the previously reported value.