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

The bacteriorhodopsin (BR) is the light transducing protein which is a novel reversible medium for holographic recording and is well suited to holographic pattern recognition. Wavelet transform is a very useful method for image features extraction and pattern recognition. In this paper, we proposed a new pattern recognition system using BR based dual axis wavelet transform, and give the experimental result.

Jan. 01, 1900
  • Vol. 18 Issue 2 186 (1998)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The development of the first photo scanning tunneling microscope (PSTM) in China is presented. The PSTM image separation method is discussed and the superdensity PSTM optical storage is proposed.

    Jan. 01, 1900
  • Vol. 18 Issue 2 191 (1998)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Many kinds of 3 D profilometry share the drawbacks of not having enough measuring range (especially, when a big object to be tested) and existing shadow problems. A new approach is purposed, which can fit the measurement of big objects and small ones with complicated shape. The theory of spatial coordinate transformation into the 3 D profilometry is presented and the method to transform the phase information into the height of objects and to combine the results from different systems is described.

    Jan. 01, 1900
  • Vol. 18 Issue 2 199 (1998)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The optical nonlinearities of C 60 /NH 2 (CH 2) 3 Si(OC 2H 5) 3 sol and gel excited by a Nd: YAG laser with 150 ps pulse duration, 1.06 μm wavelength and 1 Hz repeation were measured using Z scan technique. Theoretical fits from the data give the value of n 2=5.6×10 -12 esu for the sol and 6.2×10 -12 esu for the gel. In addition, the more higher laser transmission of the gel at the focus than that of the sol was attributed to the strong nonlinear scattering of the sol.

    Jan. 01, 1900
  • Vol. 18 Issue 2 204 (1998)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Eu2+: BaFCl, one of the photostimulated luminescence (PSL) phosphors, was fabricated and the PSL decay curves were measured. Based on the tunneling model, we studied the PSL decay in detail. A new expression described PSL decay was derived and then was compared with the experimental results.

    Jan. 01, 1900
  • Vol. 18 Issue 2 208 (1998)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The process of laser induced plasma shock wave turning into acoustic wave is discussed. It is concluded that the weak limitation of the laser induced plasma shock wave is just the acoustic wave. The laser induced plasma acoustic wave is defined, and its forms are obtained through experiment.

    Jan. 01, 1900
  • Vol. 18 Issue 2 212 (1998)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    In unannealing Yb: YAG crystals, the absorption peak positions of the color center were located at the wavelengths of 375 nm and 625 nm, and its concentration was increased with doping concentration of Yb 2O 3. The formation mechanism of the color centers was discussed. Large quantity of color centers were produced in Yb: YAG crystal under γ irradiation. In order to improve the fluorescence lifetime of Yb3+ , the color centers should be eliminated.

    Jan. 01, 1900
  • Vol. 18 Issue 2 247 (1998)
  • [in Chinese], [in Chinese], and [in Chinese]

    The motion equation satisfied by an induced polarization of a two level atom interacting with laser pulse is derived by using a nonperturbation method. And the process of high order harmonic generation in the two level system are analyzized dynamically for different forms of the equation at different laser intensities.

    Jan. 01, 1900
  • Vol. 18 Issue 2 166 (1998)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The Output property of phase conjugation enhanced by the effect of incoherent erasures upon Ce: BaTiO 3 self pumped phase conjugator is studied. This result is experimentally achieved by using incoherent beam illumination along the c axis  direction of the crystal when a He Ne laser generates steady phase conjugate signal. In the cases of the incident position of the erasure beam gradually movement, it is found that the reflectivities are increased by incoherent erasure beam. The results is analyzed and discussed.

    Jan. 01, 1900
  • Vol. 18 Issue 2 171 (1998)
  • [in Chinese], [in Chinese], and [in Chinese]

    According to the uncertainty principle in quantum mechanics, the relationship between the coherence of a light source and its light beam is discussed. The spatial coherence of X ray beam from the synchrotron radiation is analysed. Some requirements for X ray beam in the experiment of X ray coherent optics is presented.

    Jan. 01, 1900
  • Vol. 18 Issue 2 176 (1998)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The electroluminescent mechanism of organic thin film is introduced. Several kinds of electroluminescent devices (the single layer of Alq; the double layers of PVK as a hole transport layer and Alq as an emitting layer; the double layer of PVK doped with perylene and Alq) are fabricated, and the EL spectra, J V, B V, efficiency of the devices are investigated. By the energy theory, the characteristics change of all devices is demonstrated. When the hole transport layer of PVK is used, the efficiency of double layer device is 10 ̄100 times higher than the efficiency of single layer device, and the highest quantum efficiency is 0.15%(photons/electrons). The luminous efficiency is 0.08 lm/w, the brightness is changed as the thickness of the hole transport layer and emitting layer are modulated.

    Jan. 01, 1900
  • Vol. 18 Issue 2 217 (1998)
  • [in Chinese], and [in Chinese]

    The design of a diffractive reflective hybrid singlet is presented to replace a conventional doublet telescope objective. As the telescope objective has a large relative aperture (1/2.5) and a small filed of view, its spherical and lateral chromatic aberrations are high and should be corrected, while its aberrations relative to the field of view, such as astigmatism and distortion, are natually small. According to the analyzation of the primary aberrations of a hybrid singlet with a plano convex substrate, the design method of the original configration is studied. A hybrid singlet in visible band (λ from 656.3 nm to 486.1 nm) is successfully designed. In comparison with the traditional construction, this hybrid singlet, with much smaller monochromatic aberrations and nearly equal chromatic aberrations, has lower weight, greatly simplified configuration and only one material K9 used. It shows that the application of hybrid singlets in visible band is promising.

    Jan. 01, 1900
  • Vol. 18 Issue 2 223 (1998)
  • [in Chinese], [in Chinese], and [in Chinese]

    Based on the phase modulation of binary optics, the binary phase only masks are used to couple the elliptical Gaussian beam to single mode fiber. By the wavefront conversion of the beam, two pieces of the phase only masks are used to transform the elliptical Gaussian beam to symmetric Gaussian beam, and then coupled well with the single mode receiving fiber.

    Jan. 01, 1900
  • Vol. 18 Issue 2 228 (1998)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The peak value position shifting technology for spectral response of multialkali photocathodes is studied. The peak value position of spectral response of multialkali photocathodes can be controlled to meet the needs of different spectral response characteristices of various photoemissives devices. For sounding reflectance of night sky and spectral reflection on some materials, the peak value position of spectral response of multialkali photocathodes can be moved to 0.8 μm by multi information measuring techniques.

    Jan. 01, 1900
  • Vol. 18 Issue 2 233 (1998)
  • [in Chinese]

    The design idea for Cassagrain system with three aspherical surfaces is presented. A design result for focal lenth of 2.8 m, F/5.6, field of view 3.2°, is obtained. The primary and secondary mirror have six order terms aspherical surfaces and the field lens has four oder terms aspherical surface. The image quality is close to the diffraction limit and the distortion is also corrected.

    Jan. 01, 1900
  • Vol. 18 Issue 2 238 (1998)
  • [in Chinese], [in Chinese], and [in Chinese]

    The phase characteristics of the linear chirped laser pulse with Gaussian temporal and Gaussian spatial structure is studied by using the stable phase point method while propagating in vacuum. And under the second order approximation, its spatial and temporal characteristics are discussed. The conclustion from the two methods is that the Gaussian laser pulse will degenerate into a spherical wave or into a planar wave under the paraxial approximation in the very far distant while traveling in vacuum.

    Jan. 01, 1900
  • Vol. 18 Issue 2 182 (1998)
  • [in Chinese], [in Chinese], and [in Chinese]

    Using the Wigner Weisskopf approximation, the dark state effect in a Raman type photoionization system is studied. Driven by two quantum fields, a dark state is formed from three discrete states of the system, which does bot decay to the contunuum for a long period. The effect of photon number on the poulation trapping is discussed.

    Jan. 01, 1900
  • Vol. 18 Issue 2 129 (1998)
  • [in Chinese], and [in Chinese]

    By surveying the time evolution of the atomic dipole squeezing and amplitude squared squeezing, the two mode field second order squeezing and higher order squeezing in a generalizeded two mode Jaynes Cummings model, the relations between atomic dipole squeezing and second order squeezing in the radiation field are studied. The relations between atomic amplitude squared squeezing and higher order squeezing in the radiation field are discussed. The properties of the transformation between atomic dipole squeezing and field squeezing are explored.

    Jan. 01, 1900
  • Vol. 18 Issue 2 135 (1998)
  • [in Chinese], and [in Chinese]

    We show that the refular pumping statistics and atomic coherences can reduce the field noise of multiple one photon optical bistability, but can not result in field squeezing from an ordinary vacuum. If a squeezed vacuum is injected into a cavity, almost perfect photon number squeezing can be obtained in the upper branch. It is verified that the critical values of cooperativity C are related with the atomic coherences and atomic population.

    Jan. 01, 1900
  • Vol. 18 Issue 2 141 (1998)
  • [in Chinese], [in Chinese], and [in Chinese]

    Using the modified effective Hamiltonian for non degenerate Raman process, we calculated the evolution of the atom inversion and studied the influence of AC Stark shift on the collapse revival phenomenon of Rabi oscillations. It is shown that in the presence of AC Stark shift, the atom inversion in non degenerate Raman process has a beatiful periodicity, and the frequency and amplitude of the Rabi oscillation are affected by AC Stark shift.

    Jan. 01, 1900
  • Vol. 18 Issue 2 147 (1998)
  • [in Chinese], and [in Chinese]

    Electron electron correlation is more significant in negative ions than neutral atoms, often dominating the atomic structure of the ion and the cross section for interaction with an extrenal field. The negative carbon ion (2s 22p 3) and (2s 12p 4) levels, wavelength, radiative lifetime and photodetachment are discussed. The double states (1s 22s 12p 4) of negative carbon ion are more steady than its quartet states. The wavelength between (2s 22p 3) and (2s 12p 4) is located near XUV and 6 strong wavelengths are given. It can offer material for X ray laser.

    Jan. 01, 1900
  • Vol. 18 Issue 2 250 (1998)
  • [in Chinese], [in Chinese], and [in Chinese]

    A novel distributed interference fiber optic sensor system for long distance measurement is proposed based on Machelson interferometer using a modulated laser (Frequency modulated continuous wave). By incorporating an optical loop with a frequency shifter in the reference optical path of Machelson interferometer, the measurement range of the sensor system has been increased 4 times and reached 48 meters.

    Jan. 01, 1900
  • Vol. 18 Issue 2 253 (1998)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    More detailed absorption transitions of C 60 in the UV/visible region are observed from the third order derivative absorption spectra. The spectra are fitted with Lorentzian line shapes, and the transition energies and broadening parameters are determined. The assignment of the transtions in visible region is discussed,and some vibronic modes are given. In comparison with normal absorption spectrum technique, the third order derivative absorption technique has been shown an effective method for the study of optical and physical characteristics of atom clusters such as C60.

    Jan. 01, 1900
  • Vol. 18 Issue 2 152 (1998)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    high signal to background ratio in the persistent single photon and photongated spectral hole burning materials using polarization spectroscopy was obtained. The polarization spectral hole burning mechanism and high SBR method in experiments are reported. It shows that the polarization spectral hole burning technique has widely prospets for the application in frequency domain optical storage and high resolution spectroscopy in solids.

    Jan. 01, 1900
  • Vol. 18 Issue 2 160 (1998)
  • [in Chinese], and [in Chinese]

    High antireflective coatings were dip coated by sol gel method with tetraethylorthosilicate (TEOS) as precursor and ammonia as catalyst. Base heat treatment was used to strengthen the coatings. The strengthened coatings possess remarkable abrasive/scratch and irradiative resistance. The coatings can be used on the optical pumping elements in high power laser system. The obtained average transmittance of the coatings within 570~800 nm band can be increased up to more than 98%.

    Jan. 01, 1900
  • Vol. 18 Issue 2 242 (1998)
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