Performance tests, For 81628b only – Atec Agilent-81618A User Manual

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Performance Tests

Performance Tests

Agilent 81618A/9A and Agilent 81622B/3B/4B/6B/7B/8B User’s Guide, Second Edition

Performance Tests

The performance tests given in this section includes the Accuracy

Test, the Linearity Test, the Return Loss Test (for the

81622B/23B/26B/ and 27B) and the Noise Test. The performance tests

for the Agilent 81624B/6B also include – as optional tests – the

Relative Polarization Uncertainty and the Relative Interference

Uncertainty Test. Perform each step in the order given, using the

corresponding test equipment.

N O T E

Make sure that all optical connections are dry and clean. DO NOT USE

INDEX MATCHING OIL. For cleaning, use the cleaning instructions

The optical cables from the laser source to the 8156A Attenuator and

from there to the power meter must be fixed to the table to ensure

minimum cable movement during the tests.

NOTE

For 81628B only

The performance test for the 81628B High Power Head does not differ

from the test procedure for an optical head without an integrating

sphere, except for the linearity test. The integrating sphere of the

81628B has to be disconnected for testing the linearity of the head

alone. A special adapter and a disconnecting tool are necessary for

disconnection. These tools are included in the Performance Test Kit

(order P/N 81628-68705).

If the integrating sphere is disconnected the performance of the

81628B has to be verified. If performing a performance test on the

81628B that includes the linearity test, it is necessary to start the

procedure with the linearity test and then perform the accuracy and

noise tests afterwards.

The non-linearity of the 81628B is not normally tested up to the

specified power level of +38 dBm. The linearity test only verifies the

linearity of the head without the integrating sphere up to 10 dBm

(equivalent to 40 dBm with the integrating sphere). The attenuation of

the integrating sphere is typically 31

± 1 dB, hence the maximum input

power for the photodiode is in the range 6 - 8 dBm and so the test

described below covers this input power range of the photodiode. The

contribution of the sphere to the non-linearity is caused by the heating

of the sphere due to applied power > 30 dBm. These linearity

characteristics are determined by sample testing of the 81628B in

OCMD’s metrology lab.