IEC 60793-1-4:2001

Provides methods for measuring the cut-off wavelength of single-mode optical fibres. The test method applies to a sample fibre in either an uncabled condition, or in a cable, or as a jumper cable. All methods require a reference measurement, with either a bend-reference technique or a multimode-reference technique.

Establishes uniform requirements for measuring macrobending sensitivity for category B1 to B4 single-mode optical fibres at 1550 nm and of category A1 multimode fibres at 850 nm and 1300 nm. The standard gives two methods for measuring macrobending sensitivity: power monitoring and cut-back.

Four methods are described for measuring chromatic dispersion: (a) phase shift, (b) spectral group delay in the time domain, (c) differential phase shift, and (d) interferometry. Methods (a), (b) and (c) apply to class A1 graded-index multimode fibres and class B single-mode fibres. Method (d) applies to single-mode fibres, class B1 to B3 in the 1000 nm to 1700 nm wavelength range. The methods can be applied to laboratory, factory and field measurements of chromatic dispersion.

Gives two methods for monitoring the changes in optical transmittance of optical fibres and cables that occur during mechanical and environmental testing. It provides a monitor in the change of optical transmission characteristics arising from optical discontinuity, physical defects and modifications of the attenuation slope. The methods are the change in transmittance by transmitted power, and by backscattering. They apply to both multimode and single-mode fibres.

Two methods are described for measuring bandwidth: impulse response and frequency response. Both methods apply to the measurement of bandwidth of category A1 multimode fibres. Application to other categories of class A multimode fibres is under study. Neither method applies to measurement of type B single-mode fibres.

Establishes uniform requirements for measuring the attenuation of optical fibres. Four methods are described: (a) cut-back, (b) insertion loss, (d) backscattering, (d) modelling spectral attenuation. Methods (a), (b) and (c) apply to all categories of class A multimode fibres and class B single-mode fibres. Method (c), backscattering, also covers the location, losses and characterization of point discontinuities. Method (d) has been demonstrated only on class B fibres.

Establishes requirements for measuring the mode field diameter (MFD) of fibres. Four methods are described: (a) direct far-field scan: (b) variable aperture in the far field: (c) near-field scan: (d) bi-directional backscatter using an optical time domain reflectometer. All four methods apply to type B single-mode fibres, operating near 1310 nm or 1550 nm. The contents of the corrigendum of July 2002 have been included in this copy.