http://hdl.handle.net/11133/127 2004-03 Sun, 26 Apr 2026 20:02:03 GMT 2026-04-26T20:02:03Z http://hdl.handle.net/11133/1238 タイトル: 高調波モード同期ファイバリングレーザにおけるリング長制御特性 著者: 森, 正和; 松永, 雅規; 濱田, 正敏; 西澤, 典彦; 後藤, 俊夫; 後藤, 了祐; 丸橋, 大介 抄録: The ring length control of harmonically mode-locked Er-doped fiber ring lasers was improved to tolerate large and abrupt ambient temperature changes. By speeding up the control loop response, and also by isolating Er-doped fibers from abrupt temperature changes, a ring length change as large as 3.8 μm/sec could be compensated, and stable mode-locked operations were obtained. Also the lasing characteristics under stable operation, especially the dependence on the lasing wavelength, were investigated. The output pulses were transform-limited Gaussian in most cases, but pulse trains of shorter pulse width with double-peak spectra were observed under certain conditions. Tue, 30 Mar 2004 15:00:00 GMT http://hdl.handle.net/11133/1238 2004-03-30T15:00:00Z http://hdl.handle.net/11133/1233 タイトル: 半導体レーザを用いた画像膨張による進入検出センサ 著者: 田中, 徹; 津田, 紀生; 山田, 諄 抄録: Since the conclusion of Kyoto Protocol, the necessity for rationalization of energy use has been increased. Therefore, it is advisable that an escalator is controlled to pause during no user. Now a photo-electric sensor is used for escalator control, but a pole to install the sensor is needed. Then, a new type of approach sensor using the semiconductor laser and the CCD camera has been studied. The laser beam which focused perpendicularly by the cylindrical lens is irradiated at a target in only the field I of the interlace video signal, and is observed by a CCD camera. The irradiation area of laser beam is obtained by subtracting field II from field I. If the area is increasing in time, it will be judged that the target is approaching. Moreover, the error decreases by using a visible-light cut filter, and it is found that application for an approach sensor mountable into escalator is possible. Tue, 30 Mar 2004 15:00:00 GMT http://hdl.handle.net/11133/1233 2004-03-30T15:00:00Z http://hdl.handle.net/11133/1234 タイトル: cw光注入によるFabry-Perot LDの全光制御モード同期における偏波特性とスペクトル線幅の狭窄化 著者: 森, 正和; 濱田, 正敏; 松永, 雅規; 西澤, 典彦; 後藤, 俊夫; 後藤, 了祐; 丸橋, 大介 抄録: The polarization characteristics of four-wave mixing components generated by cw light injection in Fabry-Perot laser diodes were experimentally investigated. Only TE components were detected irrespective of the polarization of the injected cw light. Also, in order to apply the all-optical mode locking technique to a wide variety of laser diodes, methods to reduce the spectral linewidths of Fabry-Perot laser diodes were investigated. A simple method, which utilizes the reflection at the end of optical fibers coupled to LD rear facets, proved to be useful in spectral linewidth reductions. Tue, 30 Mar 2004 15:00:00 GMT http://hdl.handle.net/11133/1234 2004-03-30T15:00:00Z http://hdl.handle.net/11133/1235 タイトル: 圧縮芯をもつ鋼製橋脚の耐震性能実験 著者: 加藤, 剛也; 青木, 徹彦; 鈴木, 森晶 抄録: Since the Great Hannsin Earthquake, many reaerches had been done on the steel bridge piers but few works had presented for high performance of seismic resistance. In this study, new idea inproving the ductility of steel bridge piers are proposed, in which steel piers have a central core column. Compareing with usual piers, the same number of test specimens are served for seismic repeated loading as pier models with central core columns. The test results show the excellent high seismic performance than the normal ones. Tue, 30 Mar 2004 15:00:00 GMT http://hdl.handle.net/11133/1235 2004-03-30T15:00:00Z