V-1-02-EN
Light Meter. User Manual
Sensor
Device Description
Device Description
The MTTS Light Meter is single measurement unit suitable for over-
head and bed type phototherapy. It has 2 sensors loc on both sides of
the meter.
Device Description
Display
ON/OFF button
Sensor
Batteries compartment
ON/OFF button is the ‘touch type’. Place the finger on the
touch panel, do not press hard
Measuring Irradiance
The MTTS Light Meter is a spectroradiometer that measures the ther-
apeutic irradiance (radiant power) of neonatal phototherapy lights. It
measures the irradiance of the wavelengths from 440 to 465 nanom-
eters (nm), the blue-green portion of the spectrum, which includes the
principal action spectrum of bilirubin.
Units of Measurement
The MTTS Light Meter measures irradiance in units of microwatts
per square centimeter per nanometer (µW/cm2/nm). A nanometer is
a measure of wavelength equal to one-billionth of a centimeter. The
term “per nanometer” indicates the average irradiance per nanom-
eter across the spectral band being measured, which is 50 nm wide.
This makes it possible to compare average irradiance across spectral
bands of different widths.
Instrument Response Characteristics
The figure below represents the nominal response characteristics of
the MTTS Light Meter, which matches the action spectrum of bilirubin
as closely as possible.
390
10
20
30
40
400 410 420 430 440
Wavelength
%
440 450 460 470 480 490
07
06
