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31.
S. Iwama N. Satomi M. Yamanaka S. Goto T. Ishimura H. Ito 《International Journal of Infrared and Millimeter Waves》1981,2(6):1199-1208
A high-power CW 27.972 m water vapor laser has been constructed in order to use as a light source of an interferometer for plasma diagnostics. The laser consists of 220 cm length and 2.0 cm small bore Pyrex glass discharge tube, semi-confocal resonator and Michelson coupler. From the measurement of cavity detuning curves, it is found that two waveguide modes, EH11 and EH21 oscillate. The increase of the output power is found to become more than seven times larger by adding He(50%)–H2(50%) mixed gas. Under the optimum condition, the maximum output power of 65 mW or the output power per unit cavity volume of 83 W/cm3 is obtained. 相似文献
32.
Optical Review - A novel color removal method for digital color images is proposed. In this method, differences of colors in an input color image are reflected effectively, and the perceived... 相似文献
33.
Rotationally resolved ultrahigh-resolution fluorescence excitation spectra of the S1 ← S0 transition of dibenzofuran have been observed using the technique of crossing a collimated molecular beam and the single-mode UV laser beam. 3291 rotational lines of the band and 3047 rotational lines of the band have been assigned. The band has been found to be a b-type transition, in which the transition moment is along the twofold symmetry axis of this molecule, and only the ΔKa = ± 1 transitions were observed. The excited state is identified to be the S11A1(ππ∗) state. In contrast with this, the band has been found to be an a-type transition in which the transition moment is along the long axis in plane. It indicates that the intensity of this vibronic band arises from vibronic coupling with the S21B2(ππ∗) state. We determined the accurate rotational constants and the molecule have been shown to be planar both in the ground and excited states. 相似文献
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38.
Koji Nonaka Hidehiko Takara Atsushi Takada Kentaro Uchiyama Yoshiaki Yamabayashi 《Optical Review》1998,5(6):331-333
An optical mono-stable multivibrator laser diode (MM-LD) is realized by using a multi-electrode distributed feedback laser diode. All-optical pulse-width conversion of ultra-short pulses to non-return-to-zero (NRZ) is achieved using an MM-LD. The MM-LD is adopted for a wide range of bit-rates between 2-10 Gbit/s by tuning the DC bias. Data format transformation from 10-Gbit/s return-to-zero optical signals to NRZ optical-signals is achieved with error free operation. Converted optical signals, which have a narrower spectral bandwidth and lower peak power than when input, are transmitted using a 1.3-μm zero dispersion fiber (1.3Aλ0-SMF). 相似文献
39.
Ryushi Goto 《Communications in Mathematical Physics》1998,198(2):469-491
We shall use an infinite dimensional hyper-K?hler quotient method to obtain hyper-K?hler 4 manifolds of type A
∞ and D
∞. Hyper-K?hler manifolds of type A
∞ and D
∞ are constructed in terms of Dynkin diagrams of type A
∞ and D
∞ respectively. A hyper-K?hler manifold of type D
∞ is the minimal resolution of the quotient space of a hyper-K?hler manifold of type A
∞ by an involution. Finally we shall show that a hyper-K?hler manifold of type A
∞ can be considered as the universal cover of elliptic fibre space of type I
b
.
Received: 18 July 1997 / Accepted: 14 April 1998 相似文献
40.
The dynamics of semiconductor lasers with photorefractive phase conjugate optical feedback are experimentally studied. Photorefractive fringes considered here are rather static compared with time fluctuations of laser output power. Therefore, it is expected that a semiconductor laser with photorefractive feedback shows similar dynamics to those with conventional optical feedback. We examine relaxation oscillation and external cavity modes of laser output power in the presence of photorefractive phase conjugate feedback. It is proved that the dynamics of photorefractive phase conjugate feedback are fundamentally the same as those of conventional optical feedback. 相似文献