A novel resonator with two parallel cylindrical lenses is reported to improve the beam quality factor. The stable cavity condition is obtained by ABCD law and equivalent G parameter method. Experimental results show that the beam quality factor in the horizontal direction M 2 x=1.231, it is less than half of the M 2 x=2.672 obtained from the regular stable cavity.

The filtering characteristic of acousto-optic tunable filter (AOTF) is very sensitive to the change of the ambient temperature, so the ambient temperature can be obtained from the changing central frequency of AOTF′s filtering characteristic. Using the idea, a novel temperature sensor based on AOTF is fabricated. The temperature range measured by the new temperature sensor is from -40℃ to 150℃, and the precision can be up to 0 001℃. Furthermore, a kind of distributed temperature sensors to supervise and control the temperature of many distributed sites at a central place can be developed. The novel temperature sensor has an important application in the precise and distributed temperature sensor field for these advantages.

In this paper, the theoretical base and polarized optical configurations are analyzed, a magneto-optic crystal with high sensitivity and wide frequency response range is chosen, computer simulation techniques are used to verify the optimum sensor design and components capability. Experiment results indicate good agreement between measurements and simulation at frequencies up to 2 GHz.

Using numerically calculation, it is proved that the bound and high order soliton might be formed when Gauss pulse propagated in optical fiber grating though there are extremely strong GVD around the photo band gap. The characteristic of the fiber soliton is analysed, and then the applications on the WDM system is put forward.

A new method to fabricate continuous deep relief microstructure with enzyme-etching silver halide gelatin is proposed. Imaging principle of silver halide gelatin with enzyme etching and theoretical analysis of deep etching process are given, and the relationship between etching depth and exposure with absorption is solved. It shows that the nonlinearity of etching process is caused mainly by absorption of emulsion to light. The solving scheme to the nonlinearity and the optimum technique parameters of this process are presented to achieve the good linear relationship in relief depth of 4 μm by experiment. At last, the fabrication of micro cylindrical lens array with good profile has been achieved.

The theory of longitudinal scanning in computer-generated hologram (CGH) scanner is introduced. A series of methods of how to change the position, size of the scanning curve and how to improve the quality of image are described. The computer simulating result and experimental result are presented. The paper also discusses how to scan color curve with CGH scanner and the computer-simulated result is presented.

The algorithm of image segmentation and parameters calculation for overlapping image region is studied. The method of thresholding and distance transformation is proposed. The two procedures for the image segmentation and parameters calculation are designed. Computer simulation results show that the algorithm can be processed automatically and it is suited for processing by the software or hardware.

This paper describes the possibility about the application of fiber optical flying head in the storage of the computer. Because the single-mode optical fiber with photoresist lens has some advantages, for example, light mass, simple optical-path, adjustment easy and parallel processing etc., it can become the part of hard-disc driver in computer. And same times, this paper introduced the principle of the tracking, servo, and the optical-path of reading/writing, it may be used in optical disk driver.

HGganAas Co based alloy coatings have been produced by using a 5 kW CO 2 laser with wide/narrow band beam on Ni based superalloy/45 # steel. Cross-section or vertical-section of such coatings have been examined to reveal their microstructure using phase-contrast microscope, scanning electronic microscope and X-ray diffraction instrument. The results showed the primary phase γ-Co dendrite and γ-Co+Cr 23C 6 eutectic Co-existed in the coating. Dendrite grew perpendicularly to the interface in wide band laser beam coatings and more direction in narrow band laser coatings because of heat flux. There was a white thin layer of planar crystallizing at the interface of 45 # steel substrate, and the width of the broad beam coatings was wider than that of narrow beam coatings. It was irregular and no sign of white thin layer at interface region of Ni-based alloy substrate. The results also showed that dendrite grew paralleling to laser scanning direction near top surface of the central line coatings (vertical section).

The irradiated specimens were studied by Mossbauer spectroscopy (MS). It was found that minor crystallization was produced on the surface of Fe 73.5Cu 1Nb 3Si 13.5B 9 amorphous and the crystallized phase was Fe-Si. The magnetic moment reorganization of Fe 73.5Cu 1Nb 3Si 13.5B 9 amorphous phases has taken place and atom magnetic moment direction maintains a preferred in-plane orientation. The controlled magnetic anisotropy and micro-crystallization can be obtained under the given laser power irradiation conditation.

ZnO nanopowders were synthesized by thermal physical method, which present two types of morphology, such as nanoparticles and nanowhiskers. The produced tetrapod nanowhiskers usually show four needle-like feet that originate from the center of the polyhedron. The nanowhiskers display a fantastic optical property of absorbing light, which is totally different from the nanoparticles. The nanowhiskers can enhance the absorptive ability of coating for CO 2 laser beam. The results show that the hardness and depth on the laser-hardened surface of steel 5Cr5MoSiV are improved dramatically. Compared with laser-hardening by using absorbent without the nanowhiskers, the hardening only demanded an 800 W output for CO 2 laser, saving the power as 30%.

novel semiconductor laser is proposed which could have multiwavelength cascaded by tunnel junction, and a dual-wavelength semiconductor which has two active regions is grown by MOCVD with GaAs as tunnel junction and InGaAs strain quantum well as the active regions. A ridge structure of 90 μm stripe width is fabricated. The measurement results show that the laser can have two lasing wavelengths, 951nm and 986nm, the slop efficiency reaches 1 12 W/A without coating, and the far-field FWHM are 10° and 36° for horizontal and vertical direction, respectively

Simple and efficient F-P Yb-doped fiber laser with fiber tunable reflectivity loop mirror and fiber Bragg grating as cavity mirrors is brought forward. A polarization controller is twined in the loop mirror and the optimum output ratio can be obtained easily, and the trouble of selection of different reflectivity output mirror is avoided. Also fiber loop mirror has wideband reflective spectrum, which can improve the pump efficiency and give more output power. The output power of 5.65 mW, slope efficiency of 19% are obtained when pump power is 51 mW and fiber length is 7 m.

Using a novel double-grating arrangement, a tunable Yb 3+-doped double-cladding fiber laser with a tuning range from 1037 nm to 1106 nm has been demonstrated. Because of the double-grating arrangement, the bandwidth of every tuned laser is greatly narrowed to less than 0 1 nm, and the output laser is linearly polarized light.

An alignment-free resonator is used in diode pumped solid-state laser (DPSL). A compact anti-maladjusted passive Q-switched DPSL has been developed by quasi-CW diode uneven side-pumping, and using Cr 4+∶YAG passive Q-switch, conductive-cooling, KTP frequency doubling. The laser specifications are as follows: The wavelength is 0.53 μm with flattened Gaussian beam at far field, the energy is 52.2 mJ/pulse, the output stability is 0.5%, total efficiency is 3.4%, the pulse width is ～6 ns, the repetition rate is 10～40 Hz, and the divergence angle is 2.3 mrad.

A novel measuring system is proposed in this paper, which is based on transverse Zeeman laser with low beat frequency and combined heterodyne interferometry and confocal microscopy. The range of height measurement reaches over 5 μm in term of intensity derived from the confocal system. Meanwhile the phase measurement technology is adopted to divide half wavelength by a factor of 3600, hence a resolution of 0.1nm can be attained. Accordingly the requirements of both high measurement resolution and relatively large measurement range are met simultaneously. The experimental results show that in ordinary laboratory condition, without constant temperature, the shift of phase measurement is about 15 nm. Calibration with differential dual-frequency interferometer gives the linealy correlation coefficient of 0.9999 and nonlinearity of about 10 nm.

This paper presents a method of measure large elastic rotation shaft torque based on the laser Doppler technique. It can realize dynamics observation of main drive for large mechanism equipment, which can provide the foundation of the equipment automatization and intelligentization.

The adhesion forces between the micro-particles and the dielectric surface were analyzed. The adhesion of a particle with 1.5 microns in diameter to a surface was estimated to be about 10 -6 newtons. Experimentally, the optical pressure of a focused laser pulse was used to determine the adhesion between the quartz particles and a sapphire surface. This pressure was found to be very close to the estimated adhesion. It was also shown that the capillary force was the dominant component in the experiment.

In a practical high power laser system, it may happen that all optical elements do not share the same axis, some optical components may show certain astigmatism, and laser beams may be deliberately arranged to incident at non-zero angles to the optical axis. In this work, using the 4×4 optical matrices, the method for locating the off-axial ghost points (or ghost lines) of various orders in high power laser system have been given. In addition, practical criterions of specifying real and virtual ghost points (or ghost lines) have been put forward.

The effects of spatial distribution on the experimental results are studied in spectrally resolved two-beam coupling pump-probe technique. Results may be totally different when different spatial region of probe field is chosen to be measured. Interpretation is given using the theory presented in this paper. Nonlinear refractivity and two-photon absorption of GaP are obtained by numerical fitting the experimental results. Spatial-spectral resolved signal may be obtained by using appropriate spatial gates.

In this paper, optical limiting effect is studied based on the stimulated Brillouin scattering (SBS) in a single-mode fiber. Nonlinear propagation has been numerically analyzed and computationally treated in the transient SBS progress. Optical limiting, stabilization and output pulse shape have been demonstrated when high-power laser pulses enter a fiber when SBS occurs. Experimental investigation of optical limiting performances predicted by theory has been conducted using a 100 μm-diameter fiber. The input optical signals are Nd∶YAG nanosecond laser pulses which widths are 16 ns, superior constant output energy was gained when the intensity of input pulse change in experimental regime. When the input energy varied between 100～400 μJ, the fiber system gives relative stable output energy between 65～85 μJ. So the experiment results showed the optical limiting performance based on SBS in a fiber.