LI-COR LI-600, Instruction Manual

Page: 102 / 131

Section 9. Theory of operation
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where P
width
is 667E-9 seconds
The total amount of light incident on the leaf from the
LEDs is then calculated from
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Freq
set
will be either the steady-state modulation fre-
quency Mod
rate
if not during a flash, Freq
flash
during a
rectangular flash or Phases 1 and 3 of an MPF or the cal-
culated frequency based on ramp rate during Phase 2 of
an MPF.
PAR
flr
is written to flash files during each log
point.
Dark-adapted vs light-adapted measurements
With the LI-600 fluorometer, the actinic light source is
provided by external sources unknown to the instru-
ment. The instrument cannot know if a given meas-
urement being made is on a dark-adapted leaf or not.
The user must decide which type of measurement is
being made.
Table 9-1 on the next page shows the values
being used for each configuration type. The calculated
yield uses the same equation in either case, as shown
here.
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