Special Sensors
StarBright User Manual
94
12.4.2
Dosage Measurement
Dosage is the integral of irradiance over time and is displayed as joules per square meter (J/cm²).
This measurement mode is specific to the PD300RM.
In dosage mode, StarBright measures 500 times per second, updating the dosage displayed on the
screen every ½ second.
The screen layout is similar to that of the
screen with the following notable exceptions:
There is no stop mode selection.
Dosage measurement continues for up to one hour unless stopped earlier by the user.
Figure
12-4 Dosage Measurement
12.4.3
Offset
Because Dosage is the integral of Irradiance over time, background noise that affects Irradiance
will affect Dosage as well. To overcome this, perform the following steps.
Enter Irradiance mode and go to the second set of soft keys by pressing the Right Arrow key.
Block the laser/light source under measurement and press the Offset key. This will activate the
offset feature. When active, the Offset key is reverse highlighted and the offset that is being
subtracted is shown in the upper right part of the screen.
Return to the first set of soft keys by pressing the Left Arrow key.
Set the Measuring Mode to Dosage.
The Offset stored in the Irradiance screen will be subtracted in order to provide accurate
Dosage measurements.
12.4.4
Function Limitations
When measuring irradiance, the following functions are enabled/disabled:
Average, Offset, Scale Factor, and Normalize are accessible (enabled).
Density and dBm are grayed out (disabled).
When measuring dosage, the following functions are enabled/disabled:
Average, Offset, dBm, Normalize, and Density are grayed out (disabled).
Scale Factor is accessible (enabled).