Based on the Moire effect in shadow-casting of two coded masks a new kind of optical method is proposed to map phase variation on the object image with an extended incoherent illumination. Detailed analyses are given to the relations between the functions of masks and the systems of contourlines or the background fringes. The misfocusing effect and the evaluation of the configuration parameters are discussed. It is shown that this technique has advantages over interferometry.

A new theoretical analysis of the contrast reversal images for the zeroth and other diffraction order encoded by a rectangular grating is given. According to the principle that the contrast reversion is formed by subtraction of amplitudes, this paper proposed a physical model for the transmittance of an encoded picture. By means of Fourier analysis, a correct result is derived which fits well with the experimental results.

The talbot self-imaging conditions of the plane periodical objects are presented. It is proved theoretically that restriction of the angle v, 2RaRb cos r=integer, is not a necessary condition. If the cross terms of the spatial frequencies for the unit cell of periodical object are much smaller than the main frequency terms, the restriction of the angle is not necessary. In this case, any two-dimensional periodical object can be self-imaged. The experimental results presented in this paper are in accordance with the theoretical analysis.

In this note a general orthogonal property of optical resonator eigenmodes is analyzed. The orthogonality in the (u*, U) sense of the eigonmodes U and their adjoint modes u is obtained.

This paper describes the characteristics of laser dye DPDO series which are new compounds of the 2, 6-di(p-, -m-, or o- substituted phenyl) -benzo -bisoxazols. Typical absorption spectra and fluorescence spectra of DPDO are given, and the tuning curves of dye laser with such compounds excited by N2 laser are measured. It is found that the DPDO series are working in the spectral region of 371 to 394 nm and having the conversion efficiency approximately double to that of BPBD. The DPDO series also have good pliotoohemioal stability. The outpui of dye laser does not decrease aftsr eight Jiour3 nitrogen laser excitation at 200 kW paak power and 5Hz repetition rate. The dye solution can be used at intervals and preserved for 2~3 years but yet maintains its performance. The series of DPDO can be divided into two types according to their structures. Typs I with symmetric center structure lias higher conversion efficiency buij more “red” peak wavelength than type II which has not a symmetric center.

A new method for measuring fluorescence quantum efficiencies of active ions in Nd3+: glass is described. According to the principle of photoaooustic signal, the fluorescence quantum efficiencies has been calculated with the measured values of absorption amplitudes at two absorption peaks and the amplitudes of photoacoustic signals at the same wavelengthes for the Nd3+ ions in Nd3+: glass. The obtained results are in good agreement with those calculated and measured by other methods.

The growth conditions for MBE-grown GaAs-GaxAl1-xAs DH lasers are reported which include the temperature-time cycles with a lower growth temperature, in-situ growth of ohmic contact electrode layer, and an annealing process after growth. The experiments indicate that the use of source materials with high purity, BN effusion cells, and the cryopump in the system play important roles in reducing the threshold current density of the lasers and improving their optical and electrical performance.

In this paper, variation of mode behavior in integrated twin-planar-stripe GaAs-(GaAl)As lasers with drive current and ambient temperature is investigated. The optical injection lock-in action of two active cavities and the influence of lateral-mode instability on a single longitudinal-mode operation are discussed and analysed.

Some new applications of the optogalvanic spectroscopy technique is proposed in present paper. Under fixed discharge condition, using the intra-cavity optogalvanio technique, the saturation parameters of CO laser medium and its dependence on the temperature and current have been measured. By measuring small-signal optogalvanic signal responsivity, the gain distribution and the ratio of the population of vibrational levels have been obtained and the resonance self-absorption of a few lines has been obtained and the resonance self-absorption of a few lines has been, observed. The method is simple and rapid, so it may be used for real-time measnromenl of some dynamic parameters in gas laser.

UV coherent light at the wavelegnth of 255 nm and 289 nm was generated by using a copper vapour laser and a β-BaB2o4 frequency doubling crystal. The average output power of the second harmonic is about 3.5mW and the corresponding peak power is 7W when the fundamental input is about 0.5W. The frequency doubling efficiency is 0.7%. The whole setup is very simple.

The transient SES double Stockes-line in ethylene glycol by using the picosecond pulse train generated by a Nd-glass laser system with frequency doubling KDP crystal is described. The central wavelengthes of the double Stockes lines are 6246.5A and 6288.64 A respectively. The double Stockes lines are included by the symmetric and asymmetric vibrations of (OH)2 group of ethylene glycol. SES double lines coinside with Raman spectrum of HO·CH2·OH2·OH quite well.

Modes in diffused optical waveguides with an asymmetrical Gaussian refractive index profile are treated by perturbation method in this paper. The first order perturbational approximate modal field analytical expression and a dispersion equation are obtained.

In this paper, the characteristics and parameters of the tunable diode laser fabricated by HUVG method are reported. At 12 K, the pulse threshold current density is about 370 A/cm2 and OW threshold current density is about 440 A/cm2. At 13K, current tuning rate is about 0.15 cm-1/mA; at 400 mA, temperature tuning rate is about 2.3

Stability of a six-mirror ring laser cavity for colliding pulse mode-locking is analysed by using matrix method. A simple analytical result is obtained. The results are significant for disign and alignment of the ring laser cavity.

In this paper, the influences of the residual water content on the fluorescence properties, lasing thresholds and efficiencies, and gains of the laser amplifers are studied in the Nd-doped phosphate glasses.

In order to solve the problem of automatic optimization of the weighting factor in the DLS method for automatic lens design, the concept of the uniformizing factor of weight is proposed in this paper. The merit function could be made automatically out of false local minimum during optimization by means of automatic adjustment of the uniformizing factor of weight in the program. The program and a practical example are also given in this paper.

An analytic solution for small gain to the rate equations of a lser amplifier was obtained. The conditions of getting "steady-state" pulses, and the effect of pumping on deforming of the pulses were analyzed.

This paper discussed a generalized application of Fourier self-deconvolution to IB spectrum measurement. Two methods are introduced in order to suppress the increase in high frequency region, which is caused by F. F. T.. Several examples of IR spectra are given to illustrate the application of deconvolution and self-deconvolution techniques.