A new technique for fabricating continuous relief microoptics elements is presented, in which the prehardened dichromate gelatin (DCG) is used as the recording medium and the protein digesting enzyme as developer. The experimental demonstration for this method is given as well in this paper.

In this paper, we report a quasi velocity matched electrooptic phase modulator in LiTaO3 with periodic inversion. The modulation of 57 rad at 16.25 GHz (sideband width: 1.85 THz (FWHM)) obtained experimentally is the deepest ever reported to our knowledge.

A novel four plate shearing interferometer that can adjust shearing distance freely and work in equal optical path is presented. It is used in measuring the laser wavefront radius of curvature particularly and the interferometric measurement error is smaller than ±5%(R:30～1000 meters). It also can be used in measuring the focal length of optics.

The polarization crosstalk of a TE/TM mode splitter based on a Ti:LiNbO 3 waveguide crossing is deduced by using a beam propagation method(BPM). Optimizing the configuration of the device, the theoretial crosstalk is less than -23.7 dB(TM) and -22.8 dB(TE). The crosstalks of developed splitters have been measured, and the experimental results are consistent with theory.

Highly oriented Pb(Zr 0.55 Ti 0.45 )O 3(PZT) ferroelectric thin films have been grown on an epitaxial YBCO/LaAlO 3(100) single crystal substrate using pulsed laser deposition (XeCl excimer, λ=308 nm,τ=28 ns). The YBCO layer provides a seed for PZT growth and can also act as an electrode for the PZT thin films. These heterostructures were characterized using X ray diffraction, and the surface morphologies were observed using SEM. The PZT thin film showed a remnant polarization of 21 μC/cm2 and a coercive field of 65 kV/cm. The effects of processing parameters on structures and surface morphoiogies are discussed.

Transition metallic thin films with n≈k are characterized. The optical properties of transition metallic ultrathin films and the multilayer coatings and other films are quantitatively analyzed, and their applications in neutral beam splitters and in reflection filters of narrow bandwidth and high reflectivity are discussed.

In several ways of introduction of foreign gene into plants, laser microbeam puncture is a potential and available method for transformation of foreign genes directly into plant tissue. The purpose of this research is uptaking the laser microbeam puncture technique to introduce pBI121 plasmid DNA containing GUS gene into Lotus. The laser microbeam irradiation source was a third harmonic Nd∶YAG laser. Before irradiation, the cells of cotyledon must be pretreated in high osmotic buffer. Then cultured the punctured tissues on screening media containing kanamycin to select green transgenic plantlets. After the seedings were selected on screening medium (km 100 mg/l) for three generations, we got four transgenic plants. Two of them were tested by PCR with GUS special primer. The results were positive, and proved that the GUS gene had been introduced into Lotus. We have established a laser microbeam puncture transformation system of Lotus, and proved that this system was easy to operate and replicate with relative high transformation frequency, thus providing a new way for high plant genetic transformation.

A phase decoding technique is proposed to solve the problem of phase retrieval from an optical interferogram that is overlaid with random noise and segmented discontinuity. The technique is on the basis of a composite mask matching combined with a special phase unwrapping algorithm. The computer aided analysis and experimental interferograms show that the technique can be quite efficient in phase unwrapping procedure for interferograms in which speckle noise or true phase discontinuities or both may exist.

With the change of the incidence angle of the illuminating light, the speckle pattern on the observation plane is changed. In this paper, the influence of the incidence angle on the free space Fraunhofer speckle and the image speckle is analysed in detail.

A sequential cycle cascade correlation system for wavelet transform (WT) of images and correlation recognition based on feature extracting by WT is presented. The basic structure of the correlation system consists of a usual optical correlator. In this correlator, spatial light modulators can be used as real time input device. A piece of photorefractive crystal is used as an information storage element, a vast number of signal data are recorded in Fourier transform holograms by spatially encoding reference beams, such as different spatial frequency spectra of object functions, wavelet functions and WT functions of signals. The input and output signals, and sequential operation procedures of the correlation system are controlled by a computer, which can collect the input and the output signals by CCD cameras, record them, and process them in nonlinear thresholding. In this paper, the optical analogous experimental results of wavelet transform of 2-D images and their correlation recognition are provided in the cases of 1-D and 2-D Haar wavelets. For comparison, the optical result of usual correlation experiment is also presented. It is very obvious that the wavelet transform correlation recognition possesses more high discriminability than the usual correlation recognition. In addition, some other advantages of the cycle-cascade correlation system are discussed finally.

Presented in this work is a novel fiberoptic sensor array which is made of symmetric and asymmetric periodically etched multimode optical fibers. It may be applied to detection of structural states such as stress, strain or damage assessment in smart material and structures. The principle and technology of array sensing signal processing in the artificial neural network are described. The simulation results of BP network and Kohonen network are also given.

The thermal deformation in penetration welding with a laser has been investigated as a factor which results in the elevation on the surface of the weld. Qualitative analysis of the course of thermal deformation during which elevation is made has been presented in detail. A series of laser welding experiments were done with a 5 kW CO 2 laser. The experimental results agreed well with the analysis.

In this paper, we report that a small continuous wave chemical oxygen iodine laser (cw COIL) is used as a probe to measure the small signal gain two dimensional distribution for a supersonic cw COIL of several kilowatts. A discussion for the results is given.

A large bore copper vapor laser with a 6.5 cm bore and 220 cm long discharge tube has been developed in this laboratory. A maximum output power of 106 W was achieved. The laser operated at a repetition rate of 5 kHz at the 510.6 nm and 578.2 nm lines of atomic copper. The efficiency reached 1% when the laser operated at the average output power of 95￣100 W. Some relations between output power and discharge parameters are prestented in this paper. An explanation of the physical characteristics of the large-bore CVL through a comparison of the large-bore CVL to the small-bore CVL is given.

XeCl laser pulse durations longer than 150 ns have been achieved by using a multiple stage L C sharpening circuit, increasing reflectivity of the output coupler, and adjusting concentration of HCl in the mixture of Xe/HCl/Ne. The longest pulse duration was up to 175 ns. The output energy per pulse was above 120 mJ. The study on optical fibers coupling of UV excimer laser was made . The coupling output energies of 0.4, 0.6, 0.8, and 1.5 (Diameter mm) UV silica optical fibers were 10, 29, 39, and 58 (mJ),respectively. It has made encouraging the first attempt for China-made excimer laser applications in laser-medicine field, particularly in laser angioplasty.

A definition of laser beam quality applicable to cases of laser energy use in far field is given. The impact of different factors on far field beam quality is analysed.

An exact integral solution of Maxwell equation in uniform plasmas is given in this paper. Several exact solutions, including plane wave solution, the famous nondiffracting beam solution and a new 3D nondiffracting solution, are presented by means of the integral solution.

The vertical angular selectivity of volume holographic gratings in photorefractive crystals is investigated theoretically and experimentally. The vertical selective angle and the shape of the grating degeneracy line are derived by using a simplified geometrical model relating the k vector sphere to the reference point plane. The study shows that volume gratings have finite selectivity in vertical direction, so that grating degeneracy does not occur along vertical lines.

Light propagation in double layered tissues is simulated by using Monte Carlo method in this paper. The effects of the differences of three kinds of optical parameters between double layered tissues on the total diffuse reflectance, on the total diffuse transmittance and on the intensity distributions are discussed in detail, respectively. The reasons for these effects are analyzed.

In this paper, the optical propagation property of BSO crystal under simultaneously applied electric and magnetic fields is theoretically analyzed. Jones and Mueller matrices are derived, and an electric power sensor using BSO crystal is designed.