The schematic of a novel transmission grating spectrograph and the preliminary experimental results are described.This spectrograph is corn￣ of a grazing-incidence optical system and a transmission grating. The experimental results show that it is POSSible to construct a transmission gratingspectrograph of high-efficiency and high spectral resolution.

A noval Phase-shifting method is introduced. This method, with POlarization theory and elements, is applied for Moire technique and has advantages because the amount of phase-shifting is fie-cable and suitable to be controlled by computer. The theory and experiment of this method are also presented.

The radical principle of a POlarization- independent optical isolator using YVO4 wedge is presented in this paper. The formula of the insertion loss and isolation are obtained by Jones Matrix and the configuration of the isolator is given. The authors have manufactured this kind of isolator and the experiment showed that a fiber to fiber insertion loss was 1. 04 dB,the isolation was 42 dB, the return loss was 44. 3 dB, the polarization sensitivity was less than 0. 2 dB, and the bandwidth was more than 40 nm. The dimension of the isolator is 10×10×40 mm3.

A simple model deScribing Carriers dynamics in Photoconductors via a nonlinear trasport theory of semiconductor is Proposed. Numerical calculation resluts are presented, exhibitings chaotic behavior which approaChes. Teitsworth's experimental resluts. It is indicated that the chaotic broadband noise in the power spectra of the photoconductor output would make the Photoconductor deactivated.

Following the demands of the optical antenna of the wide-band lightwave digital communication system, a bias-axis catadioptrical antenna which POssesses the features of tracking and POinting has been designed with a novel simplified Gaussian optical beam commputation model for the first time.The results of computation and experiment of the antenna are also presented, showing that they completely meet the requirments of the system.

Using a laser to clad a mixture POwder of 60 V. -% ZrO2 plus 40 V.-% Nialloy preplaced on steel 4Cr13 substrate, a comPOSite coating that consists of a pure Zro2layer at the upper region and a Ni-alloy bonding zone adjacent to the substrate is formed. The microstructural analyses reveal that the ZrO2layer exhibits equiaxed grains at the upper part and a columnar structure at the lower part and is comPOsed of t-ZrO2 Phase and 2. 9% m-ZrO2 phase distributed along the t boundary. The bonding zone presents an even solidification microstructure composed of Ni-based dendrites and interdendritic eutectics. The stratification mechanism of the composite coating is interpreted as that the insoluble melts of ZrO2 and Ni-alloy powders undergo a redistribution before solidification due to density difference and interfacial tension between these two liquid phases, and then resolidify separately.

A new two-step on-line measurement to determine particle size distributions using a laser particle sizer is proposed in this paper. The measurement principle is discussed in detail. Simulating the on-line conditions, a number of experiments using standard 18nces are carried out. The measurement results are also given.

On the bests of the airborne blue-green laser depth-measuring Pulse transmiSSion Process and treating the laser light paths propagating downward and upward the sea as different transmission processes, an airborne laser bathymetry lidar equation is obtained through the Phenomenological model of beam spreading in ocean water and the underwater finite source distant law. The depth-measuring capability of a bathymetry lidar is accurately calculated and the factors affecting the depth-measuring caP8bility of a bathymetry lidar are analyzed.

In this peper, we investigate the possibility of generating the ultrashort optical pulse in far-infrared free electron laser driven by a radio-frequency linear accelerator (RFLinac). The short electron pulse emits the optical pulse the length of which is correspondent with the length of the electron PUlse. We Present an equivalent refractivity to describe the Propegation of the optical pulse. When a moderate original Phase velocity of the electron pulse is chosen to ensure that the gum be POsitive and the equivalent refractivity monotonously increase along the relative slip distance, the leading and trailing edges will relativiely move toward the center of the optical pulse during interaction. Thus, the high-power and ultrashort optical pulse in the far-infrared region would be generated.

Stable pulses as short as 26 fs with a bandwidth of 28nm and the wavelength centred at 774 nm are generated from a self-mode-locked Ti:sapphire laser.Neither apertures nor silts are used in the cavity,the average output power of 560 mWis obtained under a 5.6W TEM00Ar+ laser pumping.The condition and characteristics for mode-locking are also discussed.

The effect that the valid resonance frequency (the measured resonance frequency ) offsets fundamental resonance frequency which is used as reference, is attributed to the presence of higher-order transverse modes in the cavity. The effect,which is mainly due to the non-orthogonality of these modes that is caused by a limited aperture or an inhonogeneous surface of the detector, has been carefully studied. The results of calculation are discussed and the relationship between the resonance frequency offset and the parameters of the cavity is generalized. Methods to minimize the effect are suggested.

We report the observation of amplified spontaneous emission (ASE) in the visible light range in silica-based single-mode optical fibers doped with Er 3+ (Er3+/Al2O3/GeO2/Sio2). Frequency-upconverted emissions were observed simultaneously in a number of visible wavelengths around 463 nm (463 nm , 475 nm , 485 nm , 494 nm , 501 nm and 510 nm), 525 nm and 540 nm (525 nm, 540 nm, 547 nm, 552 nm and 565 nm),around the second harmonic signal wavelength 656 nm (656 nm, 663 nm, 669 nm and 675 nm) and near-infrared lines (782 nm, 802 nm, 809 nm and 823 nm) when the fibers were pumped by a mode-locked, Q-switched Nd3+"YLF laser operating at 1.313 μm. We have observed an interesting phenomenon that the emission spectrum around 463 nm band likely has a cascade amplification enhancement characteristic when the fiber is reported for the first time. The nonpolarization-preserving Er3+-doped single mode fiber used in our experiment had a 6 μm diameter core and a 0.979 μm cutoff wavelength. The NA is 0.235. The Er3+ dopping level is about 500×10 -6. he fiber lengths used were 4.5 m and 3 m separately. The laser power coupled into the fiber is about several hundred milliwatts. The pump mechanism for around 463 nm is that in the first step resonant two photon absorption process the ions are excited to the 4F9/2 level from the 4I15/2 ground state, and a second resonant two photon transition connects ions', 4I9/2 state to the 2G7/2 excited state, giving rise to amplified spontaneous emissions from 2G9/2~11/2 to 4I13/2.

It is rePOrted that with some new dye molecules added to PMMA by doping and copolymerizing Prepare to solid films are Prepared. With a corona-POling method, a land stable second-order nonlinear optical coeffiCient is obtained (d33=1.26×10 -7 esu).The influences of POling condition, molecular Structure and the different type films on the magnitude and stability of NLO properties are studied in detail.

A laser field induced an electrostriction of the medium studied. Stimulated Brillouin scattering and an ultsasonic wave are produced simultaneously. A breakdown of the liquid is initiated by ultrasonic cavitation.

The sectional temperature and stress diStribution of optical films under high power PUlse laser irradiation are calculated.Thermal shock effect was analyzed. Experiment of damage induced by a Q switched 1. 06 μm laser to a ZrO2 single film reveals the thermal shock damage process and mechanism.

A certain photon hate is removed from a coherent state by the state superstition Principle. The various Properties of this kind of incomplete coherent State are studied. The resultS show that the vaccum State and the single-Photon State have great and quite different influences uPOn coherence degree and amplitude flutuation as well as photon diStribution in coherent hate. For other cases, the incomplete coherent anes exhibit very similar light Properties which oscillate attenuately and Synchronously with the variation of average photon number.

In this Paper, the stability of the Na2KSb photocathode stricken by an ultra-short pulsed laser (the wavelength is 1.06 μm and 0.53 μm, and the width of a pulse is 50 ps) is studied. The maximal value of laser power density under which photocathode can work stably is determined and discussed.

Effects of scattering Particulate and focal area as well as nonlinear absorption on damage thresholds of KDP crystals are reported. Multiple pulse laser-induced damage to KDP crystals is investigated.

In this paper the growth of Ce : Ho: LiNbO3 is rePOrted. The holographic storage properties such as the diffractive efficiency,the storage time, and the quality of the stored image were studied. Using Ce: Ho:LiNbO3 crystal as the storage medium the real time associative memory was realized.

A KTiOPO4 crystal waveguide was fabricated under the conditions of different implanted energies of He+ ions and a total dose of 2.5×10 16 ions/cm2 at the temperature of liquid nitrigon. The effective refractive index of the guided modes was measured with M line spectra after the He:KTP was annealed. The refractive index profiles of the He:KTP waveguide were calculated and Proved to be in agreement with the damage profile and the range profile.