By focusing a laser beam through a high-numerical aperture objective, a sub-wavelength focal spot is obtained, which enables the application of a laser beam in microscopy, lithography and optical data storage. In this paper, the focusing properties of a laser beam through a high-numerical aperture are studied based on the vectorial Debye diffraction theory. The intensity, phase, degree of coherence and degree of polarization in the focal field are analyzed systematically. The influence of the polarization and phase state of the incident beam on the shape of the focal spot is also investigated. It is found that the spin angular momentum of the incident laser beam will convert to the orbital angular momentum while focusing. Meanwhile, the degree of coherence and the degree of polarization of a beam can change during the focusing process. Moreover, by modulating the polarization and phase state of the incident beam, the desired shape of focusing spots can be obtained.

The application of near-infrared tunable diode laser spectroscopy(TDLAS) was investigated experimentally on gas detection, and the application on methane detection in coal mines with fiber sensor was presented. Based on gas absorption characteristics in near-infrared optical bands, with wavelength modulation on narrow-linewidth distributed feed back(DFB) laser, using harmonic detection technology, eliminating the effect of light source fluctuation and fiber jitter, the performance of measurement sensitivity is improved. By using the space division multiplexing(SDM) technology, a multi-point optical fiber sensor system for measuring methane is proposed. This method can reduce system costs, and will be adapted for requirement in harsh environments such as coal mines and so on.

A method is proposed for carrying three-dimensional (3D) image with cylinder mist screen in electro-holographic reconstruction. 360\O kinoforms of 3D object are generated by use of dynamic pseudorandom-phase tomographic computer holography (DPP-TCH) and spatial coordinate transformation. The results of numerical reconstruction with single kinoform and multiple kinoforms of each viewing angle are analyzed. Experimental system is designed for optoelectronic holographic reconstruction based on cylinder mist screen and liquid crystal spatial light modulator (LC-SLM). Experimental results show that the proposed method is capable of spatially carrying reconstructed 3D image in optoelectronic holography, and suppressing the speckle noise of 3D image.

Different fusion algorithms interpret fusion images from different aspects, which generate fusion images of different brightnesses and different contrasts. Image fusion algorithms performance analysis can reduce the uncertainty of image information and improve the image resolution. Based on the generalization of these existing fusion algorithms, these fusion images obtained by different fusion algorithms are collated by means of subjective assessment score. The experimental result indicates the pyramidal fusion algorithms and wavelet transform algorithms can improve the important characteristics and image detail, which have better adaptability than those of weighted fusion algorithms in different scene. Though weighted fusion algorithms can get higher score in special scene, it has limitation of scene adaptability. Therefore, the practical image fusion system should choose different fusion algorithms to adjust different task requirements and applied circumstances in order to acquire the optimum scene interpreting effect.

Image inpainting and some of its main techniques are briefly presented. To inpaint image, an idea to solve wavelet image inpainting extending from wavelet domain to pixel domain and its theory and implement processing are given. A wavelet image inpainting method in pixel domain based on Rudin-Osher-Fatemi(ROF) model is proposed to put the idea above into practice. Experimental results show that the method can get good visual effect of image inpainting, with higher peak signal to noise ratio(PSNR) compared with former methods, and the PSNR of damaged image increases from less than 10 dB to 30 dB after processing using the proposed method. Therefore, the wavelet image inpainting is available in pixel domain, which means that the proposed method is practicable.

In order to provide the visible span of satellite for photoelectrical theodolite, we discuss the forecast method for the visible span of artificial satellites. Three important factors including height, shadow and sunlight are analyzed. The method has been used on a certain kind of photoelectrical theodolite.Choosing INTERCOSMOS and other three satellites as samples, experimental results indicate that this method can provide accurate visible span of satellite and fulfill the requirement precision of 103.629 ms. The method reduces the waiting time and advances the efficiency of operating staffs.

Considering the thermal physical properties such as heat transfer coefficient, heat capacity, thermal expansion coefficient, and elastic modulus change with temperature, the temperature field and stress field of the synchronous powder feeding laser cladding process are conducted with direct coupled analysis using the software MSC. Marc. The residual stress distributions under different scanning speeds are studied. The stress distribution along the two paths with one on the surface of the workpiece and the other along the depth of the workpiece is measured, and the results show that the longitudinal stress is much greater than the value of transversal stress. It can be speculated that, along the laser scanning direction, the existence of the residual tensile stress caused by laser cladding is the main reason for cladding layer cracks. When scanning speed increases, the VonMises equivalent peak stress on the surface of the cladding layer also increases, and the curve becomes steeper.

The third harmonic generator is an important part of the ICF laser facility. It is necessary to adjust the KDP crystal alignment offline before it works efficiently online. The basic process of the adjusting is to measure the harmonic generation efficiency at different detuned angles by scanning the crystal, then fit the dates with multinomial function, and draw a rocking curve and decide the best angle for the harmonic generation. In this paper, a precision and automatic crystal alignment adjusting system is designed base on the theory analysis. In the experiment, the system can adjust the crystal alignment automatically, and it has an accuracy of 30 μrad in phase matching angle measurement, and 4% in conversion energy measurement.

NiAl/nano Al2O3 composite coatings are prepared on medium carbon steel substrate by electroless plating. The transverse-flow CO2 laser is employed to strengthen the coatings. The composition, microstructure and wear resistance of the coatings are characterized by energy dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), X-ray diffractometer (XRD), microhardness tester, friction and wear test (ball-on-disk). The effects of process parameters on microstructure and wear resistance of the coatings are investigated. Based on the high laser power, the fast traverse velocity and the large beam diameter, Ni0.77Al Fe0.23 intermetallics are synthesized in the coating. The microhardness of the coatings increases obviously due to the phase transformation hardening. The friction coefficient and wear loss obviously decrease after laser strengthening.

Synthetic baghdadite mineral luminescence materials Ca3(Zr,Ti)Si2O9 with different Ti content were prepared by the traditional solid-state method and Sol-Gel method, respectively. Baghdadite mineral luminescence materials prepared by the Sol-Gel method have low synthesis temperature, small and uniform phosphor particles compared with that of the samples obtained by the solid-state method. It is found that Ca3(Zr,Ti)Si2O9 with different Ti contents all exhibit greenish yellow light with peak wavelength at 531 nm by 254 nm ultraviolet. Further optical properties investigations on the rare earth doping luminescence effect of Ca3(Zr0.90,Ti0.10)Si2O9 materials were studied by introducing different rare earth ions, including Sm3+, Eu3+ and Dy3+. They all show the characteristic emission in the whole visible light region (400~700 nm), indicating that they are promising as the single-phase light-conversion phosphors for white LEDs.

The spectral characteristics of omphacite jade are analyzed by X-ray fluorescence (XRF),X-ray diffraction (XRD),ultraviolet visible (UV-VIS) and Raman spectroscopy.The result indicates that the content of Ca2+ in omphacite jade sample is high.The result also shows that omphacite jade is mainly composed of omphacite,which has the similar crystal structure to jadeite,but with the different unit cell parameter.The iron,which mainly exists as Fe2+,is of high content.Raman shifts between 683 cm-1 and 1018 cm-1 are due to symmetrical bend vibration of Si-O-Si bond and symmetrical retraction vibration within [SiO4]4- tetrahedral respectively.Therefore,omphacite jade is different from jadeite.

The optical coherence tomography(OCT) technology is used to monitor the treatment of photoaged mouse skin, which is irradiated by intense plused light(IPL). A photoaged mouse skin irradiated by ultraviolet, is treated by IPL. The OCT technology is used to observe the process of the collagen remodeling in dermis. The change of optical characteristic parameter such as attenuation coefficient during the skin rejunvenation is gotten, and the magnitude of optical-thermal damage based on the changes of optical parameter is estimated. The results indicate that IPL can be used for symptoms of photoaged skin as a nonablative method, and OCT has potential as a method for characterization of collagen remodling in vivo in clinic.

The formulas of three-dimensional (3D) electric field of radially polarized beam focusing through the interface of two dielectric media are deduced based on the vectorial Debye theory. The electric field in a defocus plan calculated by Debye theory is introduced into 3D finite difference time domain(FDTD) program as input source for the simulation of focusing process. The FDTD simulation results agree well with that calculated by Debye theory. Due to its facility of setting the structures for different media, the FDTD method is applied for simulating the problem of radially polarized beam focusing through half ball shaped nano-holes which can not be calculated by Debye theory. The focus shift and field intensity enhancement phenomena caused by the half ball shaped nano-holes are observed and analyzed.

The influence of low energy electron beam irradiation (LEEBI) on GaN-based blue LED of high power has been studied. Making use of the electron beam from the lab to simulate the space electron irradiation, We take LEEBI on blue LED, and make contrast to unirradiated LED. The changes of electrical and optical properties are studied. It′s found that the higher lighting intensity but lower forward and breakdown voltage can be obtained on irradiated LED. The experimental result has been analyzed and discussed through the mechanism of electron beam irradiation.

Polymer nanofibers have highly configurable ability and good guiding properties, which is desirable for ultracompact microphotonic devices and miniaturized photonic integrated circuits. A polymer nanofiber-poly (trimethylene terephthalate) (PTT) nanofiber with good mechanical and optical properties is introduced, which is fabricated by one-step drawing process. As a subwavelengh waveguide, polymer nanofiber has tight-confinement ability and large evanescent optical field. A varies of PTT nanofibers-based ultracompact structures and devices (such as bends, rings, M×N optical coupling splitters, and Mach-Zehnder interferometers) are described in detail. These structures and devices have advantages of compact structure and low loss. Finally, the properties and application prospects of the polymer nanofibers and nanofiber devices are summarized.

The progress of high brightness, linewidth-narrowed laser diode bar is demonstrated in detail. Popular techniques used to improve the brightness and reduce the linewidth of laser diode bar are introudced in detail. These techniques include Littrow external cavity feedback technique, spectrum beam combination, and off-axis external cavity feedback technique, off-axis external Talbot cavity technique.

The low power density and the bad beam quality of the laser diode array limit its application fields. The new developments of incoherent technology, such as beam combination, polarization and spatial multiplex, for increasing power density and beam quality are introduced. The new structure and the experimental results of different combination techniques are summarized.

In recent years, Tm-doped fiber laser aroused much attention for its superior properties such as wide tunable range, eye-safe and high nonlinear threshold. Compared with Yb-doped fiber laser, Tm-doped fiber laser is of great advantage in power rising, which has significant application prospects in remote sensing, laser radar, medical care, optical parametric oscillation and other fields. The progress of continuous-wave (CW) and pulsed Tm-doped fiber laser at home and abroad is reported. At present, CW Tm-doped fiber laser has achieved 1 kW output, and single-frequency Tm-doped fiber laser has achieved 608 W output. Moreover, higher laser output will be achieved if high-power high-brightness LD pump source and multi-stage amplifier configuration are used. With Q-switched technology, the repetition rate of pulsed laser achieves 100 kHz, and the single nanosecond pulse energy reaches 360 μJ; with mode-locked technology, the repetition rate of pulsed laser achieves 37 MHz and the average power of the picosecond pulse reaches 3.4 mW. Finally, the trend of Tm-doped fiber laser is discussed.

The main steps of studying of embedded optical fiber smart metal structure are introduced, which are metal coating for protecting the optical fiber sensors, analysis of the physical characteristics of the sensors after being metalized and embedded, and the choices of embedded metal. An electroless-electroplating method is used to protect the optical fiber for less thermal stress, which can be minimized by proper coat thickness, Young′s modulus, Poisson ratio and thermal expansion. Experiments show that the metal coats can protect the optical fiber and make the optical fiber weldable. The optical fiber sensors present good sensitivity characteristics after being metalized and embedded. However, the fiber Bragg gratings are used in most research, and their bad thermal stability makes only few methods and few host metals used in embedding the optical fiber sensors. It is believed that research of the better optical fiber sensors which can endure rugged environment when it is embedded in metal is the key problem for the study.

Active laser detection based on cat-eye effect is a new type of technique used in laser weapons. The key technology is how to describe the reflection characteristics of cat-eye effect of optical targets exactly. Several vehicle-borne, portable, ship-borne and air-borne laser weapons using cat-eye effect are introduced. Representative research methods and results are reviewed. Finally, the existent problems of cat-eye effect used in active laser detection technique are presented, and the development prospects are also discussed including the multi-system detection, the optical target parameters acquiring technique based on diffraction and interference characteristics of cat-eye effect, the closed-loop active tracking system based on the modulation effect of cat-eye system on the detection laser, and the effect of stochastic atmosphere on cat-eye effect reflected light.

Along with the development of oblique angle deposition and etching, the development of reflection coatings has been broadened by the nano-porous low-index material, which has played an important role in reducing the reflection of the wide-angle incident light and maintaining the color balance. An optimized four layers graded-index antireflection coating on H-K9L optical glass with broadband and omnidirectional characteristics designed by genetic algorithm is presented. The reflection coefficient curves are also obtained and compared with the single layer made by normal materials. It plays a very good role in reducing reflectivity for the visible light when the incident angle ranges from 0° to 75°. The total average wide-angle visible spectral reflectivity can be reduced to 0.21% in this scope.