Title:
OPTICAL PATH TESTING METHOD
Document Type and Number:
Japanese Patent JP3244251
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To effectively carry out measurement of characteristics of an optical path by setting an attenuation of light receiving attenuator in a photo-pulse testing apparatus automatically and at a high speed.
SOLUTION: A photo-pulse testing apparatus comprehends a control command sent out of a controlling apparatus by a CPU 11 and automatically adjusts the attenuation of a light receiving attenuator 19. At first, the attenuation of the light receiving attenuator 19 is so adjusted as to keep the backscattering level in a part near an optical path within a prescribed range of light receiving level. In the case where the light receiving level in the far end direction is higher than the backscattering level in a near end part, the attenuation of the light receiving attenuator 19 is increased by a prescribed value by pulse width. Fresnel reflection higher than the backscattering level in the near end part and in the farthest end direction is made to be an optical path terminal and the attenuation of the light receiving attenuator 19 is so adjusted as to make the light receiving level in the near end direction from the optical path terminal not exceed a prescribed light receiving level and then measurement of characteristics of the optical path is started.
Inventors:
Yoshitaka Enomoto
Nobuo Tomita
Nobuo Tomita
Application Number:
JP20561195A
Publication Date:
January 07, 2002
Filing Date:
August 11, 1995
Export Citation:
Assignee:
Nippon Telegraph and Telephone Corporation
International Classes:
G01M11/00; G01M11/02; (IPC1-7): G01M11/00; G01M11/02
Domestic Patent References:
| JP6331494A | ||||
| JP5312672A | ||||
| JP5231983A |
Attorney, Agent or Firm:
Seiko Yoshida