Bili Meter

BiliBlanket Light Meter II

BiliBlanket* Light Meter II provides a reliable measure of light emissions from phototherapy systems.

Measuring Irradiance

The Bili-Meter is a spectroradiometer that measures the therapeutic irradiance (radiant power) of neonatal phototherapy lights. It measures the irradiance of the wavelengths from 425 to 475 nanometers (nm), the blue-green portion of the spectrum, which includes the principal action spectrum of bilirubin.

Units of Measurement

The Bili-Meter measures irradiance in units of microwatts per square centimeter per nanometer (pW/cm2/nm). A nanometer is a inmsure  of wavelength equal to one-billionth of a centimeter. The term "per nanomcter" indicates the average irradiance per nanometer across the spectral hand being measured, which is 50 nm wide. This makes it possible to compare average irradiance across spectral bands of different widths.

Instrument Response Characteristics

Figure 4 represents the nominal response characteristics of the Bili-Meter, which matches the action spectrum of bilirubin as closely as possible.

Figure 4 Nominal response of the Bili-Meter