Keysight Technologies 86120B, Руководство пользователя

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Specifications and Regulatory Information
Definition of Terms
Definition of Terms
Wavelength Range refers to the allowable wavelength range of the optical input signal.
Absolute accuracy indicates the maximum wavelength error over the allowed envi-
ronmental conditions. The wavelength accuracy is based on fundamental physical
constants, which are absolute standards not requiring traceability to artifacts kept at
national standards laboratories. Four He-Ne gas lasers are used. First, there is an
internal 632.991 nm-vacuum (473.6127 THz) reference laser
1 . To verify absolute
wavelength accuracy, three external lasers are measured during manufacturing with
these wavelengths:
730.685 nm, or 410.2896 THz
2
1152.591 nm, or 260.1032 THz 3
1523.488 nm, or 196.7804 THz 3
Differential Accuracy indicates the maximum wavelength error in measuring the
wavelength difference between two signals that are simultaneously present.
Minimum Resolvable Separation indicates the minimum wavelength separation of
two laser lines required to measure each wavelength simultaneously. Two laser lines
closer in wavelength than the minimum resolvable separation are not resolved and
one average wavelength is displayed.
Display Resolution indicates the minimum incremental change in displayed wave-
length.
Amplitude Calibration Accuracy indicates the maximum power calibration error at the speci-
fied wavelengths over the allowed environmental conditions. The amplitude calibra-
tion accuracy is traceable to a National Institute of Standards and Technology
(NIST) calibrated optical power meter. NIST is the national standards laboratory of
the United States.
1. Obarski, G. E. 1990. “Wavelength Measurement System for Optical Fiber Communications” NIST
Technical Note 1336 (February): 18. Take the average of the two frequencies straddling gain center.
2. Moore, C. E. 1971. “Atomic Energy Levels as Derived from the Analysis of Optical Spectra: Vol.
1” NSRDS-NBS 35, Vol. 1 (COM-72-51282) (December): 77.
3. D. A. Jennings, F. R. Peterson, and K. M. Evenson. 1979. “Frequency measurement of the 260-
THz (1.15 micron) He-Ne laser” Optics Letters Vol. 4, No. 5 (May): 129-130.