公开(公告)号：DK241483D0

公开(公告)日：1983-05-27

申请号：DK241483

申请日：1983-05-27

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： COPPA GIANNI ,  VITA PIETRO DI ,  POTENZA MARCELLO ,  ROSSI UMBERTO

IPC: G01M11/02 ,  G01N21/41 ,  G02B6/00 ,  G01M

公开(公告)号：DE3684097D1

公开(公告)日：1992-04-09

申请号：DE3684097

申请日：1986-11-12

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： CAPONI RENATO ,  COPPA GIANNI ,  DI VITA PIETRO

IPC: G01M11/02 ,  G01M11/00 ,  G02B6/00

Abstract: The method of measuring mode field radius in single-mode optical fibres comprises the modulation of an optical beam by means of a spatial filter with radial-distribution of transmittivity of Gaussian type. Modulated beam intensity is measured in correspondence with the beam axis for different widths of the Gaussian curve, and the mode field radius is derived from both such intensity values and a parameter dependant on the Gaussian width. The apparatus which implements the method is also provided.

公开(公告)号：DE3583926D1

公开(公告)日：1991-10-02

申请号：DE3583926

申请日：1985-12-09

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： COPPA GIANNI ,  DI VITA PIETRO

IPC: G01J1/00 ,  G01J1/02 ,  G01J1/42 ,  G01J4/00 ,  G01M11/00 ,  G01R29/08

Abstract: A method and an apparatus are provided wherein a light beam is passed through a slit (7) oscillating with respect to the beam, and a periodic signal is obtained from the beam portion traversing the slit and is split into its spectral components. Moment values are derived from the values of the amplitudes of such components.

公开(公告)号：DE3675992D1

公开(公告)日：1991-01-17

申请号：DE3675992

申请日：1986-04-16

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： CALZAVARA MASSIMO ,  COPPA GIANNI ,  DI VITA PIETRO

IPC: G02B6/24 ,  G01M11/00

Abstract: An optical beam is injected into a single-mode (FO) fibre of a given length and outgoes from an end face of the fibre, is reflected by a reflecting optical system into said fibre; the optical power of the reflected beam guided backward by the fibre is measured. Said end face of the fibre is placed in the optical centre of the reflecting system to obtain the maximum reflected power, and is then deviated from said position detecting the occurring reductions of the reflected optical power.A device and variants to implement the method are also described.

公开(公告)号：DE3573019D1

公开(公告)日：1989-10-19

申请号：DE3573019

申请日：1985-06-03

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： COPPA GIANNI ,  DI VITA PIETRO

IPC: G01M11/00 ,  G01M11/02 ,  G01M11/08

Abstract: The process is based on the fact that the introduction of perturbations in an optical fibre can generate greater losses on higher order modes. Therefore, a spectral scanning of the fibre output power is effected under a certain number of different perturbation conditions and the values obtained are combined so as to determine the fraction of power guided in the fundamental mode. The cut-off wavelength is that where this fraction exceeds a certain value. The equipment implementing the process is also provided.

公开(公告)号：IT1179877B

公开(公告)日：1987-09-16

申请号：IT6825684

申请日：1984-12-18

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： COPPA GIANNI ,  DI VITA PIETRO

IPC: G01M11/02 ,  G01M11/00 ,  G01N21/41 ,  G02B6/00 ,  G01N

公开(公告)号：AT25290T

公开(公告)日：1987-02-15

申请号：AT83105581

申请日：1983-06-07

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： COPPA GIANNI ,  DI VITA PIETRO ,  POTENZA MARCELLO ,  ROSSI UMBERTO

IPC: G01M11/02 ,  G01N21/41 ,  G02B6/00

公开(公告)号：IT1155284B

公开(公告)日：1987-01-28

申请号：IT6714982

申请日：1982-02-10

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： COPPA GIANNI ,  GREGO GIORGIO

IPC: G01B11/06 ,  G01J9/04 ,  G01N21/35 ,  G01N21/45

Abstract: The invention is based on phase difference measurements. A Zeeman effect laser (3) generates a light beam (4) containing two radiations with slightly different frequencies whose beat is generated at the end of a path external to the material (1, 2a, 101). The same beam is split into the two component radiations (4c, 4d); the beats are generated between the first radiation, which is made to follow a path outside the material, and two radiations obtained by making the second radiation follow two different paths inside the material. The phase differences of these two beats with respect to the first are measured by a phase-comparison system (20, 21), and the refractive-index values as well as the thickness values are obtained by suitable computing means.

公开(公告)号：CA1214556A

公开(公告)日：1986-11-25

申请号：CA466723

申请日：1984-10-31

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： COPPA GIANNI ,  DI VITA PIETRO ,  ROSSI UMBERTO

IPC: G01J1/02 ,  G01J1/42 ,  G01J9/00 ,  G01M11/00 ,  G01R29/08 ,  G02B6/10 ,  H04B17/00

Abstract: The value of a transverse moment of any order of the electromagnetic field associated with an optical beam (and in particular the spot size of such a beam) is determined by two successive measurements of the optical power of the beam: one measurement is a direct measurement, whilst the other is effected after spatially modulating the transverse distribution of the electromagnetic field by a factor proportional to the n-th power of the transverse coordinate of the beam, n being the moment order. The moment can be obtained from the ratio between the two measurements. The invention also includes apparatus for carrying out the method.

公开(公告)号：AU550243B2

公开(公告)日：1986-03-13

申请号：AU1502783

申请日：1983-05-27

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： COPPA GIANNI ,  VITA PIETRO DI ,  POTENZA MARCELLO ,  ROSSI UMBERTO

IPC: G01M11/02 ,  G01N21/41 ,  G02B6/00 ,  G01M11/00