Systems and methods for a distortion monitoring system that detects an abnormal amount of signal distortion occurring in a transmission system. The distortion monitoring system includes a system amplifier section (28) for amplifying (34) and coupling (32) an input signal to provide first and second (38) outputs and a distortion monitoring section (29) for processing the second output. The amount of distortion present is represented by an output from the distortion monitoring section (29) of the system. In one embodiment, the distortion monitoring section can include an envelope detector (40) for receiving the second output signal (38), a lowpass filter (44) coupled to the envelope detector for cutting off frequencies below the Nyquist rate, and a voltage amplifier coupled to the lowpass filter for amplifying the signal. An analog to digital converter (48) coupled to the voltage amplifier digitizes the signal, a memory buffer (52) coupled to the analog to digital converter captures the digital data from the analog to digital converter, and a digital signal processor (54) extracts the converted signal. In yet another embodiment, the digital signal processor (54) includes an on-chip memory. A status monitor coupled to the output of the distortion monitoring section (29) provides for monitoring the output signal.

Distortion monitoring system for CATV transmission networks

A method and a device for monitoring a cable system in the field of communications are provided. An optical signal emitted by an optical source to a transmission link of the cable system is divided into two paths of optical signals, in which one path of optical signals serve as local coherent light, and the other path of optical signals are transformed by multipath frequency shift to multiple paths of detection optical signals of different frequencies. A monitoring result is obtained by performing coherent detection, with the local coherent light, on the returned optical signals of the multiple paths of detection optical signals of different frequencies. The device includes an optical source, a multipath frequency shift module, and a coherency module.

Method and device for monitoring submarine cable system

PROBLEM TO BE SOLVED: To provide a fiber laser device, a laser beam machine, and a laser beam machining method which achieves high efficiency and high power with a simple configuration SOLUTION: The provided fiber laser device is provided with: an exciting combiner having a first multimode optical fiber propagating excitation light, a first signal light propagation fiber capable of propagating laser light, and a synthetic melted portion obtained by tying together a part of the first multimode optical fiber and a part of the first signal light propagation fiber, melting the parts of the fibers, and extending the parts of the fibers; and a returning combiner having an active fiber that is optically coupled to the synthetic melted portion and can oscillate or amplify the laser light, a second multimode optical fiber that has a light returning portion for returning a part of the residue of the excitation light to the active fiber, a second signal light propagation fiber capable of propagating the oscillated or amplified laser light, and a branch melted portion that is obtained by tying together a part of the second multimode optical fiber and a part of the second signal light propagation fiber, melting the parts of the fibers, and extending the parts of the fibers and can be optically coupled to the active fiber COPYRIGHT: (C)2010,JPO&INPIT

Fiber laser device, laser beam machine, and laser beam machining method

Provided are an optical transmission medium, a ferrule, an optical termination connector, an optical structure and an optical apparatus that have functions of an optical termination and an optical connector without exchanging components in accordance with applications. An optical transmission medium is characterized in that at least one end is defined as an APC cut surface and a refractive index matching member is arranged on the APC cut surface. A ferrule is characterized in that at least one end is defined as an APC polishing surface and a refractive index matching member is arranged on the APC polishing surface. An optical termination connector is characterized in comprising a ferrule holding an optical transmission medium and an adapter, from one side of which the ferrule is inserted, wherein the optical transmission medium has at least one end defined as an APC cut surface and a refractive index matching member is arranged on the APC cut surface.

Optical transmission medium, ferrule, optical termination connector, optical structure and optical apparatus

PROBLEM TO BE SOLVED: To provide a combined weighing-counting device, capable of improving durability of a storage device for storing combinationally selected articles on a collection shoot, and improving performance of the device. SOLUTION: For each shutter 32 of the storage device 31, a storage surface of the shutter 32 for storing the articles M thereon is set at an inclined angle with the angle orthogonal to an article dropping route D, so that adjacent shutters 32 do not hit each other when opened, therefore hitting between adjacent shutters 32 occurring when opened as before can be avoided, to thereby improve the durability of the shutters 32. A storage part 17c of the articles in the collection shoot 17 for storing the articles is equipped with an inner surface 62 lowered from the gliding surface 60 of a part on the upstream side, therefore a preceding article in the storage part 17c is dropped onto the inner surface, and then a following article is also dropped and is piled up thereon. Therefore lining-up and lengthwise linking of the articles can be prevented, and the articles are seldom bitten into, when the shutter 32 is closed, to thereby reduce damages to the articles.

Combined weighing-counting device

PURPOSE:To provide the optical amplifying method which can improve the pump efficiency of an excited beam and can efficiently amplify a signal beam even without using any LD for large output pump. CONSTITUTION:At the optical amplifying method to amplify a signal beam (a) transmitted through an optical amplifier 1 by inputting an excited beam (b) from an LD 2 for pump to the fiber type optical amplifier 1 which Er is doped, in the excited beam (b), an unused excited beam (c) not used for optical amplification is extracted from the signal beam (a) on the output side of the amplifier 1, and the extracted unused beam (c) is returned to the fiber type optical amplifier 1 and used as the excited beam again.

Optical amplifying method

PURPOSE: To provide the open circuit detecting method of optical transmission lines capable of surely and correctly detecting the open circuit of individual branch optical transmission lines with an OTDR installed on a center side. CONSTITUTION: The monitor light with different wavelengths is transmitted to individual branch optical transmission lines 2 1 , 2 2 ...2 n from an OTDR 3 at a center 1 side via a WDM. The reflected light from the individual branch optical transmission lines 2 1 , 2 2 ...2 n is monitored by the OTDR 3 to detect the open circuit of the branch optical transmissions 2 1 , 2 2 ...2 n . COPYRIGHT: (C)1993,JPO&Japio

Open circuit detecting method for optical transmission line

PURPOSE:To prevent the deterioration in a video image by superimposing a modulation signal light from a stimulated laser depending on a detected signal component onto a signal light from a laser diode so as to decrease the distortion signal component of a base band CONSTITUTION:A monitor PD (photo diode) 13 monitors the signal light of an output waveform from an optical amplifier 12 and outputs a photoelectric- converted signal to a control circuit 14 The circuit 14 adjusts the frequency band of the input signal to a base band and detects the distortion signal component of the same frequency as the frequency of a video period signal included in the signal An oscillator 15 adds a modulation signal to a excited laser 16 by direct luminance modulation based on the control of the circuit 14 and the laser 16 outputs the modulation signal light subjected to electrooptic conversion to the optical amplifier 12 based on the modulation signal from the oscillator 15 and superimposes the signal onto a signal light from the laser diode 11 Thus, the signal level of the distortion signal component of a base band is decreased and the signal light without the distortion signal component is outputted

Optical signal transmission method

PURPOSE:To prevent light from being reflected at the opened terminal of a beam splitting line in a beam splitting communication system. CONSTITUTION:A ferrule 10 is housed in the housing 9 of a terminating equipment 7 connected to the connector of the beam splitting line, and an optical fiber cord 11 functioned as a terminal optical fiber is housed in this ferrule 10. A space part 13 is provided on the rear end face of the ferrule 10, namely, on the side of a rear end face 12 of the optical fiber cord 11, this space part 13 is filled with a matching oil 17 whose diffraction factor is larger than the core of the optical fiber cord 11, the rear end face 12 is immensed in the matching oil 17, and optical signals made entered from the front terminal side of the optical fiber cord 11 are outputted to the side of the matching oil 17 with no reflection.

Terminating equipment for beam splitting line

PURPOSE:To prevent light from being reflected at the opened terminal of a beam splitting line in a beam splitting communication system. CONSTITUTION:A ferrule 10 is housed in the main body 9 of a terminating device 7 connected to the connector of the beam splitting line, and an optical fiber cord 11 functioned as a terminal optical fiber is housed in this ferrule 10. A slope 13 is provided on the rear end face of the ferrule 10, namely, on the rear end face of the optical fiber cord 11 so as to transmit optical signals entered from the front terminal side of the optical fiber cord 11 to an outside without reflecting them.

Handa Morio

Papers

Optical amplifying method

Open circuit detecting method for optical transmission line

Optical signal transmission method

Terminating equipment for beam splitting line

Terminating device for beam splitting line