Acta Optica Sinica
Co-Editors-in-Chief
Qihuang Gong
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

An algorithm for the extraction of speckle displacement is presented. It performs the two-dimensional discrete cross-correlation of the sub-specklegrams from different specklegrams in the frequency domain and thus improves considerably the speed of a cross-correlation calculation. For more accurate measurements of the displacement field the level-limiting technique is introduced to reduce the noise, and to optimize the correlation filter for obtaining a narrower and higher correlation peak to provide the optimum estimate of the peak position.

Jan. 01, 1900
  • Vol. 20 Issue 4 489 (2000)
  • [in Chinese], and [in Chinese]

    Being an available method of information fusion, image fusion has been used in many fields such as military applications, remote sensing, machine vision and medical images. Three image fusion algorithms are presented based on pixel-level including weighted mean of the original images, Toet algorithm, and the algorithm based on wavelet transform. Four kinds of quantitative evaluation criteria for the quality of image fusion algorithms are proposed such as standard deviation, average error, peak signal noise rate and the difference of entropy between the ideal image and the fusion image. Using the four algorithms to merge the fluorescence image and transmission image, the conclusions of the quantitative evaluation and the human vision are similar.

    Jan. 01, 1900
  • Vol. 20 Issue 4 494 (2000)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    In astronomical high resolution image reconstruction, Fourier modulus recovery is as important as the phase recovery of a object, because there are many kinds of complex noise in observations and the recovery of modulus or phase will become more difficult. To solve the problem of the noise of all kinds in the modulus recovery, some appropriate methods are provided. The experimental results of image reconstruction show that these methods are effective and necessary, they ensured the high precision modulus recovery.

    Jan. 01, 1900
  • Vol. 20 Issue 4 501 (2000)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    By using an optical fiber Michelson inteferometer and a super-luminescent diode with a coherent length of about 25 μm, an experimental setup of optical coherence tomography was developed. A two demensional image of a sample dipping in milk was obtained by this setup.

    Jan. 01, 1900
  • Vol. 20 Issue 4 509 (2000)
  • [in Chinese], [in Chinese], and [in Chinese]

    The optical fiber transducing technique is used to realize a measuring range multiplication system in distance measurement. It consists of two interferometers, one is used for tuning to optical path and positioning target, the other is used for measuring distance. Long distance and high accuracy measurement up to 1 meter can be realized by inserting an accurately calibrated optical fiber without long track.

    Jan. 01, 1900
  • Vol. 20 Issue 4 514 (2000)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A new method has been proposed to realize fine optical proximity correction (OPC) with gray-tone coding mask instead of gray-tone mask. The advantages of the new method are analyzed. The coding rules of the gray-tone coding mask and the relationships between the gray-tone coding mask and gray-tone mask have been discussed. OPC simulation results are given with the gray-tone coding mask and the synthesis area deviation of aerial image drops 10% after OPC.

    Jan. 01, 1900
  • Vol. 20 Issue 4 518 (2000)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A self-pumped phase-conjugate interferometer is proposed to measure vibration amplitudes of a rough surface. The distorted wave front of the light diffusely reflected from the rough surface is reconstructed by phase conjugation. Using this interferometer, the vibration-amplitude distribution of a stainless steel sample with a rough surface have been measured.

    Jan. 01, 1900
  • Vol. 20 Issue 4 525 (2000)
  • [in Chinese], and [in Chinese]

    Hematoporphyrin monomethyl ether (HMME) is a new photosensitzer with higher photosensitizing ability stronger photodynamic effects and selective uptake into tumor tissue. We analysed photodynamic damages of DNA with HMME as photosensitzer by Raman spectroscopy and obtained at following conclusions: The conformation of DNA has changed from normal B form to modified B′ form. A part of hydrogen-bonds between two bases of pair were broken. The base stacking collapsed to some extent and bases were damaged. Guanine and cytosine were more sensitive to HMME.

    Jan. 01, 1900
  • Vol. 20 Issue 4 529 (2000)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Based on the digital high-sensitivity fluorescence microscope, the ultra-high-sensitivity fluorescence microscope is developed. The system can enhance the fluorescence intensity more than 106 and get the photon sensitive image of ultra-weak fluorescence. The accurate position of ultra-weak fluorescence can be confirmed by image fusion methods. Because the speed of image acquired system is 25 frame/s, the dynamic characters of fluorescence intensity can be investigated. Using the novel microscope to study the apoptosis of MGC-803 cells induced by As2O3, the density of Ca2+ in apoptotic cells obviously increased. Ca2+ is probably one of important roles in the process of MGC-803 apoptosis induced by As2O3.

    Jan. 01, 1900
  • Vol. 20 Issue 4 533 (2000)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The principle of measurement of the phase noise by the means of phase-amplitude conversion via F-P cavity is theoretically analysed. The influence of the cavity parameters on the measurement is discussed. The theoretical analyses are used as valuable references for the design of experiment. The phase noise of LD is measured experimentally.

    Jan. 01, 1900
  • Vol. 20 Issue 4 465 (2000)
  • [in Chinese]

    The effects of round-trip optical length fluctuation (ROLF), assumed to be an ergodic random process, on a fiber-optic ring resonator (FORR) are analyzed in detail. The results show that the effects of small slow ROLF are the same as the temporal coherence of input light, which makes the FORR effective bandwidth to be broadened. But the effect of small rapid ROLF is different, its effect on the effective bandwidth is very small. However if the ROLF is great enough, the FORR will lose its bandpass and bandstop characteristics. These results are verified experimentally.

    Jan. 01, 1900
  • Vol. 20 Issue 4 472 (2000)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Time-dependent characters of the three-photon-coupling process of OPO has been calculated and the effects of a series of parameters such as pump intensity, time delay, crystal length, cavity length and output coupling coefficient have been analyzed. Calculation results presaged the existence of “relaxing oscillation” in travelling-wave OPO. By using a new kind of uncoated ring cavity,the tuning range from 0.41 μm to 2.4 μm and energy conversion efficiency of 22% have been obtained experimentally. The consistency between theory and experiments is demonstrated.

    Jan. 01, 1900
  • Vol. 20 Issue 4 478 (2000)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The absorption characteristics of the Nd:YVO4crystal and the relations between the laser output power or the slope efficiency and the input power are studied. It is found that the slope efficiency of Nd:YVO4laser dropped with the input power raised under the condition of a high power pumped. The average slope efficiency of 71.5% is obtained with a Nd:YVO4crystal of 0.5% dopped concentration x and pumped by about 5 W, the output power of the laser is about 3 W.

    Jan. 01, 1900
  • Vol. 20 Issue 4 484 (2000)
  • [in Chinese], and [in Chinese]

    The phase-matching of high-order harmonic generated in rare gases confined in a hollow fiber wave-guide is studied theoretically. A cutoff intensity for a certain phase-matched harmonic is found in calculations. The calculations show that a ultrashort-pulse laser and the medium with higher ionization potential is necessary for generating higher-order phase-matched harmonic. The possibility of selective generation of a certain order or several orders of harmonics in the hollow fiber wave-guide is discussed, and some measures of improving the possibility of selectivity for a certain order or several orders of harmonics are advised.

    Jan. 01, 1900
  • Vol. 20 Issue 4 433 (2000)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    By numerically integrating the one-dimensional time-dependent Shrodinger equation, the high-order harmonic generation (HHG) spectrum of a model atom irradiated by two-color coherent fields with frequency ω and 1.5ω is calculated respectively. It is found that there exist odd harmonics, even harmonics and semi-integer harmonics due to the coherent interaction between two colors. The origin of these harmonics and main factors influencing the harmonic efficiency are discussed in detail.

    Jan. 01, 1900
  • Vol. 20 Issue 4 440 (2000)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The absorption spectra and the dispersive properties of atomic sodium in the vicinity of 589.0 nm has been measured by using an improved Mach-Zehnder interferometer configuration when an additional coherent driving field at 589.6nm is applied. The corresponding theoretical calculation has been given based on the four-level model.

    Jan. 01, 1900
  • Vol. 20 Issue 4 446 (2000)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A novel technique for fiber Bragg grating displacement sensor temperature-induced wavelength-shift passive compensation is introduced. With a step thickness isosceles triangle shape cantilever beam, a fiber grating glued on the surface along the beam axis across the thickness border is employed to sense the free end displacement. The experimental sensitivity of 9.24×10-2 nm/mm is obtained, which agrees with the theoretical value 9.4×10-2 nm/mm very well.

    Jan. 01, 1900
  • Vol. 20 Issue 4 538 (2000)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Aerial image distribution of a 0.35 μm contact hole with traditional mask, rim phase shifting mask (PSM), partial rim PSM, attenuating PSM are calculated based on Hopkins model, and the optimum parameters of different PSM are obtained. Attenuated PSM in enhancing resolution and improving the depth of focus in photolithography is of the most effective among them, especially when partial coherent factor (σ) is small.

    Jan. 01, 1900
  • Vol. 20 Issue 4 543 (2000)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A scattering polarizer is prepared by using polymer networks formed from an amorphous monomer, nematic liquid crystals and polyimide-coated ITO glass substrates. The polyimide layers are rubbed with anti-parallel directions, thus liquid crystal molecules with homogeneous alignment along the direction of rubbing can be obtained, and further stabilized by polymer networks. Due to electro-optical properties of polymer network liquid crystals, and impinging polarized beam is scattered or transmitted depending on its polarization direction parallel or perpendicular to that of rubbing, respectively. In the parallel case, light scattering intensity can be adjusted greatly under low electric field; in the perpendicular case, light transmission is very high and hardly adjusted electrically. This kind of device combining with a linear polarizer can be switched in a high contrast ratio and fast response. The detail fabrication process is presented, and the experimental results are given and discussed.

    Jan. 01, 1900
  • Vol. 20 Issue 4 548 (2000)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Effect of surface roughness of Be window on the spatial coherence of hard X-ray beams is investigated by means of digital simulation, in which the interference pattern of one fiber in-line holography is employed to estimate the coherence. A simple model for X-ray reflection from rough surface is proposed. Based on this model, effect of surface roughness of reflection mirror on X-ray beams, including hard X-ray and soft X-ray, is simulated. The result from simulation is consistent with that from experiments.

    Jan. 01, 1900
  • Vol. 20 Issue 4 553 (2000)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The error of the quantum controlled-not operation in an ion trap is treated. By introducing a measurement of projection, the error can be reduced to be a small quantity, or a second-order small quantity in some particular cases. The limitation of this scheme is discussed.

    Jan. 01, 1900
  • Vol. 20 Issue 4 451 (2000)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The effect of a squeezed vacuum input on the bistable behavior of a ring cavity with three-level atoms in Λ configuration is investigated. It is shown that the squeezed vacuum input significantly increases the range of the optical bistability. The optical bistability can be controlled by the appropriate squeezed vacuum input.

    Jan. 01, 1900
  • Vol. 20 Issue 4 456 (2000)
  • [in Chinese], [in Chinese], and [in Chinese]

    The principle of the atom lens using a hexapole magnetic field and its aberration has been discussed. Comparison of the focusing results of a hot atomic beam with a monochromatic cold atomic beam shows that the main factor affecting the imaging quality of the magnetic lens is chromatic aberration. The use of laser cooling atomic beam technique can greatly reduce this aberration and makes the magnetic lens a useful tool in the field of atomic optics.

    Jan. 01, 1900
  • Vol. 20 Issue 4 460 (2000)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The Focusing Tomography is presented to reconstruct the 3-D radiation in a luminous body. The 3-D luminous body could be considered as the combination of many 2-D parallel luminous sections. Focus on each section by only one camera, a group of images will be captured which is the overlapped image of one focused image and other defocused images. The irradiances of these images form governing equations. The irradiance distribution of different sections could be induced from above equations. In this experiment, several light emitting diodes are employed to simulate several luminous sections. Results show that this method can reconstruct the irradiance of each section.

    Jan. 01, 1900
  • Vol. 20 Issue 4 570 (2000)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Jan. 01, 1900
  • Vol. 20 Issue 4 573 (2000)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Jan. 01, 1900
  • Vol. 20 Issue 4 575 (2000)
  • [in Chinese], [in Chinese], and [in Chinese]

    The cyanine thin films were prepared by spin-coating process. The transmission, reflection and absorption spectra of the cyanine films were measured by spectrophotometer. The refractive index n, k were calculated from the ellipsometric spectrum. The results of the dynamic measurement and optimum recording power measurement indicate that CNR can be reached up to 47 dB at different traveling rate and the optimum recording power is about 7 mW. The dimensions of the deformed area of CD-R under different writing power were measured by atomic force microscope.

    Jan. 01, 1900
  • Vol. 20 Issue 4 560 (2000)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A azo dye-doped polymer thin film has been made by spin-casting method on single-crystal silicon. The optical parameters of the film have been measured at a scanning ellipsometer with the analyser and polarizer rotating synchronously in the wavelength region of 350~800 nm. The results show that the film has a strong and broad absorption in the region, and the aggregation state of the dye molecules greatly influences its absorption spectrum.

    Jan. 01, 1900
  • Vol. 20 Issue 4 565 (2000)
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