Title:
EQUIVALENT REFRACTIVE INDEX OF LIGHT TRANSMITTING MEDIUM AND INSTRUMENT AND METHOD FOR MEASURING REFRACTIVE INDEX
Document Type and Number:
Japanese Patent JP3276033
Kind Code:
B2
Abstract:
PURPOSE: To measure the refractive index from an arbitrary waveguide mode in which light is being transmitted through the light transmitting medium of a light transmission device and a device and method by which the medium can be easily evaluated.
CONSTITUTION: The refractive index measuring instrument is constituted of a reflected returning light measuring instrument 5 equipped with a light source, light intensity detector 13 which measures the emitting angle distribution and emitting intensity of light emitted from an optical waveguide 2 which is a light-transmissible medium having a known length L, far field pattern measuring data processing computer 7 which calculates the equivalent refractive index and refractive index of the waveguide 2 from the different in arriving time between reflected returning light rays from the incoming end 4 and outgoing end 3 of the waveguide 2 detected by the measuring instrument 5 or the measured results of the light propagating distance corresponding to the difference, measured result of the emitting angle distribution of the light emitted from the waveguide 2, and the length L of the light transmitting medium. In addition, the measuring instrument 5 is optically connected to the waveguide 2 through an optical fiber 10, polarizer 8, rotor 9, and polarized light maintaining optical fiber 1.
Inventors:
Shinji Koike
Hideyuki Takahara
Hideyuki Takahara
Application Number:
JP17987194A
Publication Date:
April 22, 2002
Filing Date:
August 01, 1994
Export Citation:
Assignee:
Nippon Telegraph and Telephone Corporation
International Classes:
G01M11/02; (IPC1-7): G01M11/02
Domestic Patent References:
| JP5119548A | ||||
| JP4157338A |
Attorney, Agent or Firm:
Yasuyuki Tanaka (2 outside)