A mathematics model for approximating a 3D digital image is presented. The model is based on the approximation with bicubic uniform B-spline patch. The reconstruction of a spatially free-form surface with this model is also presented to prove the feasibility of the modeling method proposed.

Analytical expressions for scalar/vector angular spectrum transfer function (scalar-/vector-ASTF) of photon scanning tunneling microscope (PSTM) were derived using Fourier angular spectrum diffraction theorem. The numerical results show that the ASTF of a PSTM consists of two distinct components, the propagating component and evanescent component. For evanescent component, their amplitudes decrease dramatically, and the higher the frequency the faster the amplitudes decreasing, while the phases remain constant as tip-sample distance d increases. For propagating component, their phases increase linearly but not uniformly with d, and the lower the frequency the faster the phases increasing, while the amplitudes remain constant. It is the ability of a PSTM to collect evanescent component that makes it possible to break through the Rayleigh diffraction limit. Based on ASTF the influence of such parameters as tip-sample distance, tip aperture diameter and the incident angle of illuminating laser beam on PSTM image has been discussed.

Optical heterodyne Zeeman modulation magnetic rotation spectroscopy (OHZM-MRS) is a high sensitive spectroscopy technique. In this spectroscopy, both laser frequency and Zeeman effect of a sample are modulated, and then the signal with high signal-to-noise will be obtained by double demodulation. The expression of OHZM-MRS signal is derived, and the influences on the line shape of OHZM-MRS are discussed by the extinction coefficient of polarizers, ellipticity, phase shift induced by elliptical polarization, φ angle (where φ is the small uncrossing angle between two nearly crossed polarizers) and residual amplitude modulation. The results of theory and experiment are in agreement each other.

Laser lithography is one of the main methods for manufacturing micro-optical and the binary optical masks. The smallest linewidth produced by laser lithography plays an important role in the properties of the micro-optical elements. The collimated laser beam (He-Cd laser λ=442 nm) was focused on the photoresist for exposure and light intensity distribution in the photoresist was derived out on the approximate assumption. One of its main properties, namely lithography resolution, was analyzed based on the light intensity distribution in the photoresist. When the incident beam is modulated by the amplitude elements or the phase elements, the light intensity distribution in the photoresist will be changed, and therefore the quality of the exposure line will be affected. The results of the calculations showed: normally, 1.0 μm linewidth on photresist can be achieved, when the central circle of the incident beam is obstructed, a super resolution linewidth of 0.6 μm can be achieved for the lithography lens, microscope objects (NA=0.65, 40x). However, it requires a more rigorous exposure energy control. The experimental exposure results on the laser direct writing system showed good agreements with the theoretical calculation.

The difficulty in phase unwrapping is the key problem that compromises reliability and prevents automatic measurement in grating projection profilometry. A novel temporal phase unwrapping algorithmnon-linear excess fraction method (NLEFM) is proposed, which may extend the reliable measuring range by a factor of dozens without losing accuracy. The principle of NLEFM is detailed and experimental results are given in which complex profiles are reliably computed using this algorithm

A new roughness measurement technique, optical stylus method is presented. The principle of the new method is based on the phenomenon of light modulated by surface profile. The modulation principle, the theory of light coupled area, a optical profilometer with a single mode fiber probe and experiment results are detailed.

A novel sensor array made of multimode optical fibers twisting steel strands is presented. It can be used to detect many state parameters such as load,strain of intelligent material and structure. Optical time-dimain reflectometry (OTDR) technology is applied to process real-time parallel and distributing sensing signals. In this way, the measured datas are obtained and the identified results are proved.

The phase modulation and demodulation of interferometric Mach-Zehnder fiber-optic hydrophone using phase-generated-carrier (PGC) techniques with direct source modulation are described. The additional influence of amplitude modulation in the course of phase modulation is analyzed through rigorous mathematical calculation, and the resolution is given accordingly. To select various parameters reasonably and match them well are discussed when taking this scheme. Some experimental results concerned are given. The theoretical analysis and the experimental results are important to the study of all fiber optic hydrophone arrays and the signal detection system design.

A scheme of using a mode-locked fiber ring laser and taking the advantage of the time unevenness of the multiplexed signal to obtain the clock of the single channel from the optical time division multiplexing (OTDM) signal is proposed. In experiment, the electronic time division multiplexing (TDM) signal is used because it is identical with OTDM signal in principle. The optical clock of the single channel is obtained successfully using the electronic multiplexed signal. The result can be applied in all-optical clock recovery of the OTDM system.

Optical computerized tomography (OCT) is used practically to reconstruct the temperature field generated by the radiation of the central processing unit (CPU). The practical signifitance of the OCT is figured out. The acquisition of the multi-direction interferometry projection of the stable temperature field and similar stable temperature field is successfully solved.

The time-dependent probability of a two-mode ring laser field including both multiplicative noise and full saturation effect is obtained by the method of one-dimensional approximation. The influences of multiplicative noise and saturation effect on the two important representative physical quantities of dynamical properties of laser fieldintensity correlation time and effective eigenvalue are discussed.

The spatio-temporal propagation dynamics of unresonant pulse pairs in coherently prepared media is investigated. The effects of detunings on the phase modulation of the coherent pulses are emphasized. The results show that the ultimate amplitudes of pulse pair are decided by the initial state of the media when the pulses propagate steadily, which is same as that of resonant condition. The detunings of the system only change phase modulation of pulses.

The rate equation model is setup for the signal gain, pump absorption and output noise spectrum of bidirectional erbium-doped fiber amplifier (Bi-EDFA) including numbers of signals, pumps of arbitrary direction, amplified spontaneous emission(ASE) and inherent loss. The influences of erbium-doped fiber length, input signal power, pump style and pump power on the gain characteristis of Bi-EDFA are analyzed. Forward- and backward- noise figure for different pump style versus bidirectional input signal power is investigated. With these results, the optimal design for Bi-EDFAs in optical communication systems and networks can be performed.

A simple model of temperature field was presented for the CuBr laser discharge tube with diaphragms. An analytical expression of the radial temperature distribution in the tube was given. Theoretical analyses and experimental results show the influence of the tube structure on the discharge stability and flare quality.

The spectral and luminescence properties of (Cr4+, Yb3+):YAG crystal, and the absorption spectra of Cr4+:YAG crystal and Yb3+:YAG crystal are reported. In the absorption spectra of (Cr4+, Yb3+):YAG crystal, there are two absorption bands at 937 nm and 968 nm respectively, which are suitable for InGaAs diode laser pumping; and there is a absorption band of Cr4+ at 1030 nm, which is suitable for passive Q-switched laser output at 1030 nm. This (Cr4+, Yb3+)-codoped YAG crystal may be a promising material for compact, efficient and high-stable diode laser pumped solid-state passive Q-switched laser.

The optical nonlinearity in bacteriorhodopsin (BR) is studied. The absorption spectra of BR before and after illuminating BR are measured respectively and the result shows a great change of absorption to light. Its optical nonlinearity by Z-scan is studied, the result of the theoretical calculation shows that it has bigger optical nonlinearity coefficient than other materials. A saturable absorption at wavelength 632.8 nm is found by measuring and theoretically simulating the change of its transmissitivity with input intensity.

An amorphous polymer containing azo-side groups has been investigated regarding to the photoinduced anisotropy and polarization holographic recording. Measurements reveal that the effect of photobleaching process should be taken into account in explaining the experimental results in the azobenzene side-chain polymer film and that the polymer possesses large magnitude of photoinduced birefringence (Δn=7.8×10-3). A reversible polarization hologram with high efficiency (19.3%) is recorded with a CW 532 nm laser in this thin film.

Light-induced scattering in LiNbO3 crystal is highly dependent on the magnitude of the applied electric field. Based on the Kukhtarev and coupled wave equations, an analytical solution is given to the relation between the transmitted intensity and the differnet applied electric fields, and thus explain how the applied electric field diminish the scattering light.

A Gaussian-equivalent model of taper shape is proposed for the simulation of biconical fibers in order that the biconical fibers can be designed and fabricated easily. This model is completely characterized from the easily measured parameters. The modeling can be used to direct taper fabrication and to analyze optical properties of biconical fibers. Simulation results agree well with the experimental data.

The characteristic of the angular modulation curves of the reflectance ratio γ for p-polarized beams from both sides of coated plane glass is closely related to the optical parameters of the films. The dependence of relative gradients of γ to the refractive index n, extinction coefficient k and thickness h of the films on the optical parameters are obtained theoretically, which provides theoretical basis for the optimization of parameters. By data simulation, the resolution of refractive index of film sensor based on the calculation is predicted to be less than 10-7. It has been measured that the optical parameters of sol-gel SnO2 films under different technological conditions and the sensitivity to the testing gas. The results indicate that the method of the p-polarized reflectance can be widely used in high sensitivity optical chemical sensors.

A method for fabricating chirped fiber gratings using fiber Bragg gratings is presented. A Bragg fiber grating has been tapered by etching it in HF acid. A strain gradient along the grating was formed when a tension of 1.50 N was applied to the etched fiber grating and then a 15 mm long chirped fiber grating with a peak reflection of 92% and reflection full-width at half maxmum (FWHM) width of 5 nm was fabricated.

Computer simulation of the variable output beams produced by a single double-layer rectangular phase grating is presented. With a single element, 2, 3, 4 or 5 output beams with 72.93%, 82.48%, 71.20% or 83.04% of total diffraction efficiencies respectively can be obtained by tuning the read out angle of an incident beam. Methods for improving the optical properties of this element are discussed, and the potential applications in optical memory and optical communication are suggested.

The phase squeezing of pump light reflected from triply resonant optical parametric oscillator (OPO) has been discussed by means of the semi-classical theory. The calculated results are in good agreement with the experiments.

The superposition states, which are composed of the eigenstates of q-deformed oscillators (i.e. q-deformed number states), are presented by making use of q-oscillators algebra. The definition of this kind of q-deformed superposition states is given, and their quantum statistical properties are studied. The ordinary squeezing and q-squeezing, furthermore, the higher-order ordinary squeezing and higher-order q-squeezing of these states are discussed. The q-deformed oscillator is nonlinear oscillator, so the ordinary superposition states are generalized.

The superposition of the q-coherent states is constructed, and its quantum statistic properties (squeezing effect, antibunching effect) are discussed. The effects of the superposition coefficient and deformed parameter on these quantum statistic properties are studied with the aid of numerical calculation. The relevant results of the even and odd q-coherent states are contained in more general conclusion of this paper as special cases.

The testing of spectral responsivity of semiconductor photo detector is discussed. A device used for testing spectral responsivity with wavelength ranged from 0.4～1.1 μm is developed. It can be used to test relative spectral responsivity, absolute spectral responsivity and quantum efficiency, and the effect of instability of source can be eliminated. The testing results are compared.