The measurement of characteristics of spectra and time of ultrafast fluorescence is studied by combination of the femtosecond laser pulse and the streak camera with a time resolution better than 2 ps. The generation of fluorescence is analyzed, the way to measure time-resolved fluorescent spectra is proposed. The data of the time-resolved fluorescent spectra and fluorescent life-time of an organic optical disk named the azo dye-doped thin film are given.

According to birefringent effect of uniaxial crystal and principle of polarization interference, the design principle of Lyot filter is analyzed by using Muller matrix. The theoretical analysis shows that the rational values of the thicknesses to the minimum thickness among the plates in the filter are possible to be non-integer. Several design examples of four-stage Lyot filter which have thickness in a non-integer and integer ratio are given, together with a brief discussion and comparison about their transmission curve.

By using the Z-scan method, the nonlinear circular birefringence of an isotropic chiral medium (the pyridine solution of the polyesterimide ) for the left-handed and right-handed circularly polarized light is investigated. The law for the nonlinear optical rotation angle under the low light power is obtained. The relationship between the nonlinear circular birefringence and nonlinear optical rotation is verified.

An annealed proton-exchange LiNbO3 waveguides are fabricated and characterized in this paper. The refractive index profile after annealing is obtained by “selecting zero element” method. The empirical relations between waveguides parameter and fabrication conditions are established. The dispersion equation is also studied in guided-layer. The results are useful for applications of annealed proton-exchanged waveguides in photonics devices.

In this paper the simulating annealing method is introduced into the optimal design process to improve the long-range homogeneity along the line focus. The results show that the unequal width element CLA is able to improve the homogeneity along the focus line for an incident laser with both Gaussian and uniform distribution. The design results are also given.

With two pieces of phase gratings stored in one point of photorefractive materials, the analytic expressions for the first two higher-order harmonics of the stationary space-charge field are presented by using “the hopping model” of Feinberg. The results indicate that the fundamental and second harmonic of the space-charge field of one of grating are coupled with the second and fundamental harmonic of the other grating, respectively. The positions of the maximum values of the normalized fundamental and second harmonic of the space-charge field versus the normalized grating vector (k/k0) in two pieces of grating are deviated from that in single piece of grating. At the same time, it is found that the degree of deviation of the spatial second harmonic of the space-charge field more strongly depends on the difference of normalized grating vector (k/k0) of the two pieces of gratings than that of fundamental harmonic. Besides, the degrees of deviation for both harmonics do not depend on the modulation depths.

An anti-counterfeiting means using phase-only CGH is presented in this paper. Two phase-only CGHs are made by decomposing the phase information into two parts. When single CGH is reconstructed, no information will be observed, while two alignment combined phase-only CGHs are reconstructed, the recorded information will be read out on the image plane. Any one of the CGH can act as the decoding key. Because the phase distribution on each CGH is a random one, it is very difficult to duplicate the identical decoding CGH.

A speckle metrology technique called dynamic white-light digital speckle photography is proposed, and an automatic measurement system of dynamic displacement or strain field is developed. The system procedure is designed so that the flashing illumination, the CCD camera, the grabbing card and the analog-to-digital converter can all work simultaneously. Two specklegrams of the specimen, one before and one after the deformation are captured. The time delay between two exposures is controlled by setting a certain numeral value in the Boxcar and the dynamic displacement in the deformation process of the specimen is recorded in serial specklegrams. The system is tested successfully.

The OTF of the atmosphere imaging system is calculated and the effects of the scale of turbulence on the integral resolution are analyzed by using the approximate Andrews model of refractive index fluactuation. The results obtained for the approximate Andrews modle turbulence spectrum significantly differ from those obtained for a pure power-law turbulence spectrum.

The wavelength conversion of 2.5 Gbit/s non return-to-zero optical pulse based on cross-gain modulation in semiconductor optical amplifier is demonstrated. The separation for up-convertion is larger than 10 nm, and down-conversion is larger than 20 nm. The relationship between the receiver power and bit error rate is shown. Co-propagation wavelength conversion is used in this experiment. The signal wavelength is fixed, the probe optical signal is extra-cavity laser with the tunable wavelength. No bit error is observed after a measurement of more than one hour, which will be useful in the application of WDM optical networks.

The self-frequency doubling laser performance of Nd:GdCOB crystal with the phase-matching direction not in the principal plane is reported. The green light with a power of 11.3 mW and an efficiency of 2.3% was obtained. Laser threshold for self-frequency doubling operation is measured to be 1 mW. The experimental results are discussed.

By using Er3+-doped fiber, a single-mode fiber laser based on fiber Bragg grating was developed. When it was pumped by 980 nm laser-diode, the output spectral bandwidth was measured as 0.1 nm at 1.56 μm. The max. output power was measured as 1.73 mW. The power stability is better than ±0.02 dB, and the stability of output wavelength is better than 0.05 dB. The laser had a threshold of 7 mW and a slope efficiency of 3%.

The miniature solid state YVO4/KTP green laser with high performance has been developed. A special temperature control technique is realized and all elements in the laser are fixed into a whole with epoxy to elevate the laser efficiency, output power and laser beam point stability. A output power of 195 mW of CW 0.53 μm green laser in the TEM00 mode has been measured from the miniature green laser pumped by 1 W LD. The beam point stability is smaller than 0.01mrad per hour and 0.03mrad for 24 hours.

By changing the temperature of a semiconductor laser linearly and keeping the injection current constant, the frequency of a single mode laser can be continuously scanned up to 60 GHz. The spectrum of 2S-2P resonance transition of lithium, recorded by the method, even some hyperfine structure was clearly resolved.

In this paper, a new method of obtaining multi-coherent-beams by UR90 resonators coupled with forward-mode was given, by which a problem was called “detune” existing in method of backward-mode was resolved, and the reliability of system was enhanced obviously. The far-field intensities and divergence angles of combined beam of two copper vapor lasers with UR90 resonators coupled at small magnification (M=1.21) were measured and analyzed experimentally. The results demonstrated that the mode-control ability and far-field intensity distributions of UR90 resonators coupled by forward-mode are still good.

The gains for the three 4d→4p lasing transitions in Ni-like Ta collisional excitation X-ray lasers are studied in this paper. The study shows that gain and inversion at 4.483 nm and 5.097 nm lines are mainly contributed by collisional excitation from the ground state of Ni-like ion, while gain and inversion at 7.442 nm are mainly contributed by both collisional excitation from the ground state of Ni-like ion and recombination from the groud state of Co-like ion. In addition, the ionization rates from Cu-like ion and Ni-like ion in the important region are of the same order, which leads not only to overionization but also to low fractional population of Ni-like ion. The important role of autoionization and dielectronic capture in the ion population is also discussed. Moreover, the effect of resonance lines reabsorption is studied by escape factor method. Finally, as a result of study, the optimum region for gain in Ne/Te plane at 4.483 nm laser line is: Te≈1～1.5 keV, Ne≈(1～4)×1021 cm-3.

Characteristics of polarization control plate smoothing interference speckles produced by random phase plates are analyzed theoretically and simulated numerically. When the smoothing effect is valued by the speckle contrast over the intensity profile, the results show that the simplest two-element polarization control plate has the best smoothing effect for the far-field spot.

Angular distribution and depolarization properties of polytetrafluoroethylene diffuse reflectance plate were investigated under multiwavelength laser illumination with different beam divergences in this paper. Results indicate that this plate has a good diffuse reflectance and depolarization properties which can be used as a standard of diffuse reflectance.

According to the measured values of the refractive indices of the Nb:KTP crystal at different temperature, the expression of the thermal refractive index coefficients as a function of the wavelength is got. The thermal refractive index coefficients of the Nb:KTP crystal at the wavelength range between 539.75 nm and 1079.5 nm are calculated. The calculated values agree with the measured values well.

The NLO characters of new nonlinear crystal—CsLiB6O10 (CLBO) are introduced. The 2ω,3ω,4ω and 5ω harmonic generation of a Q-switched Nd:YAG laser were obtained with a CLBO crystal and the conversion efficiency was 60%,5%,43% and 8%, respectively. The factors which have an effect on conversion efficiency were discussed.