公开(公告)号：CA1264960A

公开(公告)日：1990-01-30

申请号：CA507721

申请日：1986-04-28

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： CALZAVARA MASSIMO ,  COPPA GIANNI ,  DI VITA PIETRO

IPC: G02B6/24 ,  G01M11/00 ,  G01N21/84

Abstract: A method and apparatus are provided for measuring optical coupling losses between single-mode optical fibres, wherein an optical beam is injected into a length of optical fibre, the optical beam exiting from a fibre end face being reflected by a reflecting optical system back into said fibre through said face, and reemerging its injection point, and wherein the optical power of the reflected beam is measured, under a reference condition in which the core portion of the end face and its image produced by the optical beam reflected by the reflecting optical system coincide at the optical centre of the reflecting optical system, as well as under conditions of transverse or longitudinal offset from the reference condition. Various types of reflecting optical systems and arrangements for aligning the apparatus prior to a measurement are described.

公开(公告)号：DE69104598D1

公开(公告)日：1994-11-17

申请号：DE69104598

申请日：1991-12-19

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： ARECCHI FORTUNATO TITO ,  CALZAVARA MASSIMO ,  GIACOMELLI GIOVANNI

IPC: H01S5/06 ,  H01S5/062 ,  H01S5/0683 ,  H01S5/40 ,  H01S3/103

Abstract: A system for the generation of modulated optical signals, wherein to the d.c. bias current of a semiconductor laser (1) associated with an opto-electronic feedback circuit (2) including a delay, there are superimposed the variations of a current obtained by detecting an optical signal resulting from the combination of an optical, amplitude-modulated input signal and of the optical signal present in the feedback circuit. By a suitable choice of the modulation frequency (f2) of the input signal and of the low-frequency gain (B) of the feedback loop (2), the laser output signal is amplitude-modulated at a frequency equal to the modulation frequency (f2) of the input signal.

公开(公告)号：IT1199897B

公开(公告)日：1989-01-05

申请号：IT6766585

申请日：1985-07-22

Applicant: CSELT CENTRO STUDI LAB TELECOM ,  LAB TELECOMUNICAZIONI S P A

Inventor： CALZAVARA MASSIMO ,  COPPA GIANNI ,  DI VITA PIETRO

IPC: G02B6/24 ,  G01M11/00 ,  G02B

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：DE69104598T2

公开(公告)日：1995-03-23

申请号：DE69104598

申请日：1991-12-19

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： ARECCHI FORTUNATO TITO ,  CALZAVARA MASSIMO ,  GIACOMELLI GIOVANNI

IPC: H01S5/06 ,  H01S5/062 ,  H01S5/0683 ,  H01S5/40 ,  H01S3/103

Abstract: A system for the generation of modulated optical signals, wherein to the d.c. bias current of a semiconductor laser (1) associated with an opto-electronic feedback circuit (2) including a delay, there are superimposed the variations of a current obtained by detecting an optical signal resulting from the combination of an optical, amplitude-modulated input signal and of the optical signal present in the feedback circuit. By a suitable choice of the modulation frequency (f2) of the input signal and of the low-frequency gain (B) of the feedback loop (2), the laser output signal is amplitude-modulated at a frequency equal to the modulation frequency (f2) of the input signal.

公开(公告)号：IT1241364B

公开(公告)日：1994-01-10

申请号：IT6803690

申请日：1990-12-21

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： ARECCHI FORTUNATO TITO ,  CALZAVARA MASSIMO ,  GIACOMELLI GIOVANNI

IPC: H01S5/06 ,  H01S5/062 ,  H01S5/0683 ,  H01S5/40 ,  H01S

Abstract: A system for the generation of modulated optical signals, wherein to the d.c. bias current of a semiconductor laser (1) associated with an opto-electronic feedback circuit (2) including a delay, there are superimposed the variations of a current obtained by detecting an optical signal resulting from the combination of an optical, amplitude-modulated input signal and of the optical signal present in the feedback circuit. By a suitable choice of the modulation frequency (f2) of the input signal and of the low-frequency gain (B) of the feedback loop (2), the laser output signal is amplitude-modulated at a frequency equal to the modulation frequency (f2) of the input signal.

公开(公告)号：CA2057649C

公开(公告)日：1995-06-13

申请号：CA2057649

申请日：1991-12-13

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： ARECCHI FORTUNATO T ,  CALZAVARA MASSIMO ,  GIACOMELLI GIOVANNI

IPC: H01S5/06 ,  H01S5/062 ,  H01S5/0683 ,  H01S5/40 ,  H01S3/103

Abstract: A system for the generation of modulated optical signals, wherein the d.c. bias current of a semiconductor laser, associated with an opto-electronic feedback circuit including a delay, is superimposed with the variations of a current obtained by detecting an optical signal resulting from the combination of an optical, amplitude-modulated input signal and of the optical signal present in the feedback circuit. By a suitable choice of the modulation frequency of the input signal and of the low-frequency gain of the feedback loop, the laser output signal is amplitudemodulated at a frequency equal to the modulation frequency of the input signal.

公开(公告)号：IT9068036A1

公开(公告)日：1992-06-22

申请号：IT6803690

申请日：1990-12-21

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： ARECCHI FORTUNATO TITO ,  CALZAVARA MASSIMO ,  GIACOMELLI GIOVANNI

IPC: H01S20060101 ,  H01S5/06 ,  H01S5/062 ,  H01S5/0683 ,  H01S5/40

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：IT9068036D0

公开(公告)日：1990-12-21

申请号：IT6803690

申请日：1990-12-21

Applicant: CSELT CENTRO STUDI LAB TELECOM

Inventor： ARECCHI FORTUNATO TITO ,  CALZAVARA MASSIMO ,  GIACOMELLI GIOVANNI

IPC: H01S5/06 ,  H01S5/062 ,  H01S5/0683 ,  H01S5/40 ,  H01S

Abstract: A system for the generation of modulated optical signals, wherein to the d.c. bias current of a semiconductor laser (1) associated with an opto-electronic feedback circuit (2) including a delay, there are superimposed the variations of a current obtained by detecting an optical signal resulting from the combination of an optical, amplitude-modulated input signal and of the optical signal present in the feedback circuit. By a suitable choice of the modulation frequency (f2) of the input signal and of the low-frequency gain (B) of the feedback loop (2), the laser output signal is amplitude-modulated at a frequency equal to the modulation frequency (f2) of the input signal.