公开(公告)号：JP2000089046A

公开(公告)日：2000-03-31

申请号：JP25647099

申请日：1999-09-10

Applicant: LUCENT TECHNOLOGIES INC

Inventor： ABRAMOV ANATOLI A ,  EGGLETON BENJAMIN JOHN ,  ROLAND PATRICIO ESPINDRA ,  HALE ARTURO

IPC: H01S3/06 ,  G02B6/00 ,  G02B6/02 ,  G02B6/34 ,  G02F1/01 ,  H01S3/067 ,  H01S3/10 ,  H04B10/17 ,  H04B10/29 ,  G02B6/10 ,  H04B10/16

Abstract: PROBLEM TO BE SOLVED: To obtain an optical fiber diffraction grating clad which is intensified in the sensitivity of material for the purpose of a reconstitution characteristic by arranging plural heating elements, generating a temperature gradient along the length of diffraction gratings, and chirping the diffraction gratings. SOLUTION: The device 9 has an optical fiber 11 of a certain length having a series of the optical diffraction gratings 12 having refractive index perturbation 13 and plural heating elements 10 along the diffraction gratings 12. The optical fiber 11 usually has a central core 14, an external cladding 15 and an external coating 16 of the temperature sensing material. The heating elements 10 are made of resistant metals for correcting the diffraction gratings 12 by local heating. When operating, the electric signals impressed to the heating elements 10 establish the temperature gradient at the coating along the diffraction gratings 12, thereby changing the refractive index of the coating. This change effectively chirps the diffraction gratings 12. The heating elements 10 are arranged at uniform intervals and are capable of establishing the desirable gradient by changing the effective heating capacity (for example, the number of coils) thereof.

公开(公告)号：JP2000066120A

公开(公告)日：2000-03-03

申请号：JP32117398

申请日：1998-11-12

Applicant: LUCENT TECHNOLOGIES INC

Inventor： ABRAMOV ANATOLI A ,  HALE ARTURO ,  MOCK JOEL LESLIE ,  STRASSER THOMAS A ,  VENGSARKAR ASHISH MADHUKAR

IPC: G02B26/00 ,  G02F1/313 ,  H04B10/02 ,  H04B10/152 ,  H04J14/00 ,  H04J14/02

Abstract: PROBLEM TO BE SOLVED: To obtain a method capable of monitoring a multiple wavelength optical system without using costly elements, such as detector arrays and an apparatus therefor. SOLUTION: The physical parameters of the intra-fiber gratings for coupling the light used in the wavelength division multiplex(WDM) optical fiber system between the spatially different mode are scanned, i.e., changed. The space modes are separated by using a mode discrimination device(MDD) 47 and the spectral components separated by the conventional or other suitable detectors 48 are monitored, i.e., detected. The peak wavelength of the coupling the two different modes to each other is changed and the coupling in the fiber optical system is controlled by scanning the intra-fiber gratings. This system uses the long- period gratings for coupling the spatially different modes for propagating the light in the two same direction to each other or the short-period gratings for coupling the mode for propagating the light in a forward direction and the mode for propagating the light in the opposite direction spatially different therefrom to each other.

公开(公告)号：JPH11202113A

公开(公告)日：1999-07-30

申请号：JP29586598

申请日：1998-10-16

Applicant: LUCENT TECHNOLOGIES INC

Inventor： ABRAMOV ANATOLI A ,  HALE ARTURO ,  VENGSARKAR ASHISH MADHUKAR

IPC: G02B5/18 ,  G02B6/02 ,  G02B6/10 ,  G02B6/293 ,  G02B6/34 ,  H01S3/06 ,  H04B10/12

Abstract: PROBLEM TO BE SOLVED: To minimize the temperature reactivity of the long-cycle diffraction grating device. SOLUTION: This device includes an optical fiber 10 having a certain length, which has a core 11 surrounded with a composite cladding including a low- refractive-index part 12 and a high-refractive-index part 13 and transmits light in waveguide mode. The two parts 12 and 13 of the cladding have lower refractive indexes than the core 11. In this case, a polymer upper coating 20 with selected optical characteristics surrounds the composite cladding. In a preferable practical style, the temperature reactivity of the long-cycle diffraction grating written to a conventional dispersion shift fiber is reduced to less than 0.40 nm/100 deg.C.

公开(公告)号：DE69801632D1

公开(公告)日：2001-10-18

申请号：DE69801632

申请日：1998-11-03

Applicant: LUCENT TECHNOLOGIES INC

Inventor： ABRAMOV ANATOLI A ,  HALE ARTURO ,  MOCK JOEL LESLIE ,  STRASSER THOMAS A ,  VENGSARKAR ASHISH MADHUKAR

IPC: G02B26/00 ,  G02F1/313 ,  H04B10/02 ,  H04B10/152 ,  H04J14/00 ,  H04J14/02 ,  H04B10/08

Abstract: Apparatus for monitoring multi-wavelength optical systems includes an optical fiber system (44) and apparatus (42) for separating the different wavelengths of transmitted light transmitted therethrough and for monitoring the respective optical power in the separated spectral components. More specifically, embodiments of the invention scan or modify the physical parameters of in-fiber gratings (46) that couple light between spatially different modes of light within a wavelength-division-multiplexed optical fiber system, separate the spatial modes using a mode-discriminating device (47) and monitor or detect the separated spectral components using a conventional or other suitable detector (48). By scanning the in-fiber gratings, the peak wavelength of coupling between two dissimilar modes is modified, thus allowing control of the coupling within the fiber optic system. Scanning the grating is performed, for example, by changing the temperature or modifying the physical dimensions of the grating. In one embodiment, the system employs a long-period grating that couples light between two co-propagating, spatially different modes. In an alternative embodiment, the system uses a short-period grating that couples light between a forward propagating mode and a spatially dissimilar, backward propagating mode.

公开(公告)号：DE69801632T2

公开(公告)日：2002-06-27

申请号：DE69801632

申请日：1998-11-03

Applicant: LUCENT TECHNOLOGIES INC

Inventor： ABRAMOV ANATOLI A ,  HALE ARTURO ,  MOCK JOEL LESLIE ,  STRASSER THOMAS A ,  VENGSARKAR ASHISH MADHUKAR

IPC: G02B26/00 ,  G02F1/313 ,  H04B10/02 ,  H04B10/152 ,  H04J14/00 ,  H04J14/02 ,  H04B10/08

Abstract: Apparatus for monitoring multi-wavelength optical systems includes an optical fiber system (44) and apparatus (42) for separating the different wavelengths of transmitted light transmitted therethrough and for monitoring the respective optical power in the separated spectral components. More specifically, embodiments of the invention scan or modify the physical parameters of in-fiber gratings (46) that couple light between spatially different modes of light within a wavelength-division-multiplexed optical fiber system, separate the spatial modes using a mode-discriminating device (47) and monitor or detect the separated spectral components using a conventional or other suitable detector (48). By scanning the in-fiber gratings, the peak wavelength of coupling between two dissimilar modes is modified, thus allowing control of the coupling within the fiber optic system. Scanning the grating is performed, for example, by changing the temperature or modifying the physical dimensions of the grating. In one embodiment, the system employs a long-period grating that couples light between two co-propagating, spatially different modes. In an alternative embodiment, the system uses a short-period grating that couples light between a forward propagating mode and a spatially dissimilar, backward propagating mode.