working range (high or low light) Press the integrate bu3on to start a measurement. Press the
integrate bu3on a second me to complete the test and view the results. Press the Profile bu3on and
expose to a flash of light to generate a graph. Flash does not save or export the results.
(Note: For silicon sensors, use seLngs to turn on the 5V bias and increase the sensors measurement
speed)
About Flash:
Typical Measurement Range:
High Light: (3 uA to 1 mA), Frequency 0-250 Hz
Low Light: (0 to 3 uA) Frequency 0-25 Hz
To determine your working range in light level (calibrated
units ie W/cm2, lux...) take the current range noted above and
divide by the calibra on factor for your sensor combina on.
For example SED270QT has a typical cal factor of 1.65e-4.
300nA equates to .000018 W/cm
2
3uA equates to .018 W/cm
2
1mA equates to 6 W/cm
2
The Flash app display:
The top row states the applica on and shows the ba3ery life.
The 2
nd
row shows the units of measurement and the cal
factor in use. Cal factor selec on in done in SeLngs.
The white display box shows the flash count in the upper le ,
(Note: Counts was designed for rapid rises in light intensity
and increases when the signal rises 4x between 100uS
samples)
the working range in the upper right (1mA for High Light and
3uA for Low Light) and the readings (ie W/cm2 instantaneous,
J/cm2 a er integra on is complete).
(reading of display can be set to Scien fic nota on on/off in
seLngs. 1.872e-2 becomes 18.72 mW/cm2 when set to off)
Below the display are the resolu on controls. The Le bu3on
←
.000 increases the number of digits shown in the numerical
display the right bu3on →.00 decreases the number of digits
.
The zero bu3on is used to measure and subtract environmental noise and/or ambient ligh ng. The
system should be warmed up, and the source to be measured should be off or blocked from the
sensors view during zero.
The integrate bu3on is used to take a measurement and toggles between start and stop each me it is
pressed.
The auto zero before integrate allows the meter to re-zero before every test which assures a correct
ambient and noise subtrac on. Note that the auto-zero opera on takes approximately 0.5s so
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