We derive a numerical method of calculating binary grating structures, which have predetermined gjatial spectra with a typical accuracy of less than one percent. As an experimental verification, we present test results of a grating that converts a plane wave into a central block of 11×11 uniformly diffracted waves.

In this paper, the reconstruction precision of Fast Fourier Transform Iteration has been studied by computer simulation with the priori knowledge of refractive index fields. The effects of increased input data error and limited total viewing angle on the precision are discussed. As an example, it has been used to reconstruct the flame temper ture fields, and the results are compared with thermocouple measurements.

Several kinds of coded pictures have been decoded using the holographic inverse filter (HIF) with wide dynamic range. The performances of the HIF are discussed. The results of imaging two-dimensional objects optically by the spiral aperture (SA) and non-rednndant array (NRA), and also, the results of imaging the three-dimenbional objects by NRA (optical tomography) are presented in the paper.

The principle, mechanism, accuracy and reliability of 19-bit and 21-bit absolute photoelectric shaft angle encoder -with high accuracy are described. The accuracy and reliability of the absolute encoder is enchanced significantly by means of interpolation of phase-shift resistance and sectionally and repeatedly correcting. The results measured are as follows: resolution accuracy σ = ±0.6 angle second, angle measurement accuracyσ2= ±1.2 angle second for the encoder of 19-bit; andσ1= ±0.2, σ22 =±0.62 respesti...

The optical design and model experiment results of a lithographic lens available to 1:1 stepper -with a numerical aperture of 0.4 and field size of 10×10mm2 are degoribed. The optical design is based on Wynne-Dyson s 1:1 oatadioptrio system and some modifications have been made. The experimental results have shown that the lens possesses submicron lithographic resolution.

In this paper, the principle of interferoinetry for determining electron density Of plasma is presented. The structure of 7-ohannel interferometer and its measurement results on HT-6M TOKAMAK are described. The light source used in the interferometer is a o. w. glow HON laser with cavity length of 3.4M and power output about 100 mW at 337μm. The averaged electron density of 7 probing chords can be given simultaneously. The detectable sensitivity its 1/15 frige with temporal resolution of 0.lms. Through asymmetrical Abel inversion from the line integrals of phase shift of 7 chords, the electron density profile at different time or three dimensional diagram of space-time distrirbutions of electron density can be obtained.

A stable resonator-with high power annular output operated at the stable boundary was studied theoretically and experimentally. In a high power transverse-flow CO2 laser with large active volume, the experimental results were obtained of output power with good beam quality and uniform near-field distribution.

In this paper we report a new type sealed-off branchseleeted CO-CO2 compound laser operating at room temperature for the first time. Approximate two handred lasing lines were obtained in the region of 5.2-6.3μm and 9.2-10.8μm. the highest output power of the stronger lines was about 2.5W(CO) and 10 W(CO2). The influence of CO2 concentration in the gas mixture, discharge current and pressure on the power distribution of the lining speotram of CO and CO2 was investigated experimentally. The excitation processes for CO and CO2 molecules in the compound laser have been analyzed.

This paper reports firstly the single- and doubleresonant β-BaB2O4 optical parametric oscillators (OPO) pumped by second harmonics of a 1.064μm Nd:YAG laser. The tuning range of OPO covers 0.83-0.89,μ\m, 0.97-1.18μm and 1.63-1.73μm. The maximum energy output of SRO (Single-Resonant Oscillator) and DRO (Double-Resonant Oscillator) s ImJ/pulse and 200μJ/pulee respectively.

Space resolved spectra with both high spectral resolution (-0.2A) and spatial resolution (-2μm) of the second harmonic emission scattered at 90°to the laser axis were observed when both narrow band and broad band laser beams were adopted in an Al planar target experiment. After analyzing many phenomena, it has been proved that the second harmonic emission observed at 90° to the laser axis is initiated by the interaction of laser with plasma filaments other than that of planar wave with plasmas. And theory is in agreement with experiment on the whole.

Many laser lines from AlΣ3a+ state to XlΣa+ state of molecular sodium were generated by using a excitation source of a dye laser pumped by a XeCl excimer laser. With the aid of a resonator, the laser output was increased by more than 10 times.

We have studied the blue-green and blue exciton series spectra of cuprous oxide (Cu2O) with electrolyte electroreflectanoe method at room temperature and performed experimental results to be the least-square fit to Aspnes theory. Comparing the fit results with the experimental results of reflection and absorption spectra at low and room temperature, we get that the electaorefleotanoe spectra of Cu2O include not only n=l exciton effect of blue-green and blue series but also n=2 exctton effect. The eleotrorefleotance spectra of CuaO with different smoothing are measured and tho obvious spectral feature different is observed.

Spectroscopic ellipsometric data, of which incident-light wavelength ranges from 3500 A to 6500 A, has been analyzed to determine the optical response of the interface between Pt and n-Si(111). The result shows an interface layer of thickness d2=30± 1 A, whose optical and dielectric properties are very different from the ones of the Pt film or the Si substrate. At the same time, the apparent optical constant spectra and dielectric function spectra of the interface layer were obtained in this work. A calculation based oil the effective medium theory (EMT) was done to fit the dielectric function spectra of the interfaoe layer. The resnlt indiDates the existence of Si-rich oxide in the interface layer, which can be ascribed to tlie reduction of the natiye Si oxide oil the suxfaoe of Si substrate caused by Pt. The restil-fc also suggests ihat the interface layer is a physical and cLemioal mixing region of Pt, Si and Si-rioh oxide.

A group-theory analysis of single crystal LAP has been made. LAP belongs to monoolinio system with space group P2, its total 222 eigen-modes are classified: Γ = 111A+111B. The polarized Raman spectra and reflected in rared spectra of LAP and DLAP have been recorded in the range of 50-3700 cm-1. The spectra lines have been assigned to different atomic groups and the oompariflion of PO43- NH3+ and COO- groups in LAP and DLAP have been made. The experimental results confirms that the symmetry of DLAP is the same as that of LAP and deuterium broadens the region oi transparent.

Optical constants and optical propeties are studied and compared of the thermal vaporated and magnetron sputtered extreme thin silver layers by using the attenuated-eotal-reflection (ATR) technique. The curves of optical constants and optical absorpta-tncevs. film thickness are determined for both deposited methods, the results agreen with the theoretical calculation.