Abstract: Jitter and waveform are improved by reducing the wavelength spectrum width of a laser beam pulse. In a laser pulse generating apparatus according to the present invention, a semiconductor laser device, a polarization maintaining optical fiber, an optical reflection filter having bandpass characteristics using an FBG whose passband can be changed by changing a tension, and an optical isolator are connected via an optical fiber. A driving circuit drives the semiconductor laser device to generate a pulse. The optical reflection filter performs filtering by transmitting a specific component of the wavelength spectrum of the pulse, reflects a portion of the optical power, and outputs the remaining optical power except the reflected portion to the outside via the optical isolator. The reflected pulse is fed back to the semiconductor laser device to thereby reduce the wavelength spectrum width of the laser beam, and improve the jitter and waveform.

Abstract: Jitter and waveform are improved by reducing the wavelength spectrum width of a laser beam pulse. In a laser pulse generating apparatus according to the present invention, a semiconductor laser device, a polarization maintaining optical fiber, an optical reflection filter having bandpass characteristics using an FBG whose passband can be changed by changing a tension, and an optical isolator are connected via an optical fiber. A driving circuit drives the semiconductor laser device to generate a pulse. The optical reflection filter performs filtering by transmitting a specific component of the wavelength spectrum of the pulse, reflects a portion of the optical power, and outputs the remaining optical power except the reflected portion to the outside via the optical isolator. The reflected pulse is fed back to the semiconductor laser device to thereby reduce the wavelength spectrum width of the laser beam, and improve the jitter and waveform.

Abstract: An alarm notifying device comprising apparatus for inputting an alarm signal of a facility to be monitored, apparatus for connecting to a mail server for delivering an electronic mail by way of a communication line, a memory for storing a guidance text corresponding to the contents of an alarm, and a CPU having the function of transmitting an electronic mail about the alarm. In the alarm notifying device, the CPU has the function of adding the contents of an alarm and a guidance text corresponding to the alarm contents to an electronic mail.

Abstract: It is the object of the present invention to provide a transmission system that transmits a control signal corresponding to the overhead accommodating time division multiplexing information at a frequency that is the same (or nearly the same) as that of the main signal. In order to attain this object, an optical transmitter broadens in a time range the optical waveform of the OTDM signal having a wavelength &lgr;0 and the control light having a wavelength &lgr;1(≈&lgr;0), and multiplexes the signal light having an optical peak intensity set low compared to the OTDM signal peak intensity and sending this to an optical transmission fiber.

Abstract: The present invention provides an alarm notifying device comprising means for inputting an alarm signal of a facility to be monitored, means for connecting to a mail server for delivering an electronic mail by way of a communication line, a memory for storing a guidance text corresponding to the contents of an alarm, and a CPU having the function of transmitting an electronic mail about the alarm. In the alarm notifying device, the CPU has the function of adding the contents of an alarm and a guidance text corresponding to the alarm contents to an electronic mail.

Abstract: An all-optical swtich apparatus having an optical gate which is unitarily composed of a nonlinear etalon and a pair of GRIN lenses, or a nonlinear etalon and a GRIN lens, and having collimating GRIN lenses, each of which guides a signal beam and a control beam to the optical gate. The resonance wavelength of the etalon can be regulated by adjusting the incident positions of signal beam and/or control beam to the optical gate by moving the collimating GRIN lenses. This decreases the required thickness accuracy of the etalon by one or more orders of magnitude than in the conventional technique.

Abstract: A take-up liner for uncured rubber members is a band-like laminate of inextensible reinforcing cloth, flexible foamed layer arranged thereon, extensible cloth arranged thereon and sheet-like elastomer layer adhered thereto and has a helical formed shape.