Admesy MSE Series, Руководство по эксплуатации

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7 Auto-ranging
7.1 Introduction
The MSE includes an auto-range function. This function is useful in case
the measured object shows an unknown luminance value. In this case, the
MSE will try to find the optimum setting which is a trade-off between speed
and the stability of the instrument. The auto-ranging function can also be
fine-tuned to reach better stability levels by setting a few parameters.
Auto-ranging can be controlled by 3 parameters.

Frequency : supposed to be frame frequency of the display that is
measured

Frames : The minimum number of frames to measure

Adjmin : The minimum level to adjust to
Adjmin is an important setting which can vary between 1 and 50.
Reasonable results will be achieved when set to 5 regarding the speed
and the stability. If high stability is needed, this setting must be increased
(but it will become slower). If a faster measurement is needed and the
stability level may be lowered a little, the value of adjmin can be
decreased. When the MSE measures in auto-range mode, it can happen
that the found integration time is very low. For example when measuring
white it may be just 5ms. When this happens, the MSE will automatically
increase the averaging so that the total measurement time equals
>= (1/frequency)
· frames.
7.2 How auto-ranging works
The auto-ranging works, by first setting a default integration time. If this
already meets the criteria for a good measurement, the measurement will
be done using that integration time. It should be clear that this is the
fastest because no adjustment will be done. In case the measured result is
either to low or too high (clip), than the MSE will adjust to a better level.
The following graph shows how levels inside the MSE work.
Fig 5 Auto-range levels
When auto-
ranging is set, the MSE will accept any level between “Adjmin”
and “Adjmax” as a good signal. The Adjmin level can be set by the user
through a software command, allowing some fine tuning of the stability and
the speed of the instrument.
adjmin level
adjmax level
clipping