V-3-00-EN
4-meter. User Manual
Operation
Operation
Additional options
4-meter offers a selection of choices for different types of measure-
ments.
Bandwidth estimator and units of measurement
4-meter measures the bandwidth of 400-520 nm. As opposed to the
traditional fluorescent light sources, LED based phototherapies are
narrow-banded. The aim of 4-meter is to estimate light source band-
width to get meaningful average values.
Given the complexity of the light measurement 4-meter offers the
user the choice of 2 measurement units:
- µW/cm
2
/nm for relative irradiance measurement and
- µW/cm
2
for absolute irradiance measurement
In the example below:
- the estimated bandwidth of the light source is 60 nm
- the top relative irradiance measured is 20 µW/cm
2
/nm
- the bottom relative irradiance measured is 40 µW/cm
2
/nm
- the total relative irradiance measured is 60 µW/cm
2
/nm
- the total absolute irradiance measured is 3,600 µW/cm
2
Change unit
Changes units between
relative irradiance (µW/cm
2
/nm) and
absolute irradiance (µW/cm
2
)
Top sensor
Activates / deactivates the top sensor. When the Top sensor is
deactivated, the top sensor bar is gray.
Bottom sensor
Activates / deactivates the bottom sensor. When the bottom sensor is
deactivated, the Bottom sensor bar is gray.
Set relative
Sets the current measurement as reference values
Show relative
Shows / hides the relative ratio of current measurement to the
previously set reference value
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