An easy-to-use instrument to accurately determine the intensity of phototherapy treatment.

The MTTS Lightmeter provides precise measurement of the intensity of the blue light spectrum that is necessary to treat jaundice in infants. This measurement allows health professionals to ensure phototherapy units are working correctly and determine when a phototherapy device or its bulbs need to be replaced.
The Lightmeter was developed for use with the MTTS Firefly and MTTS Colibri Overhead Phototherapy, but it can be used for any phototherapy unit with LEDs, fluorescent bulbs or compact bulbs. When measuring a single-sided phototherapy machine, the Lightmeter will measure the light using the front sensor. When measuring a double-sided phototherapy, the MTTS Lightmeter reads the intensity from both sides, using the sensors on the front and back of the device. It then displays the sum of the values from each side.


By measuring the wavelength spectrum from 400 to 500 nanometers, the Lightmeter gives a reliable irradiance measurement and helps to comply with the American Academy of Pediatrics Guidelines.


The Lightmeter provides a quick and accurate measurement of therapeutic light intensity from any kind of phototherapy device to make sure that the patient is receiving the most effective amount of light.


The Lightmeter can also be used as a tool for clinical decision making, allowing the care giver to determine how to position the baby, maximize light exposure, and provide the strongest phototherapy.

Key Features

– compact, handheld unit
– for the measurement of neonatal phototherapy units

– spectral response chosen to match wavelength used for Jaundice treatment
– two sided measurement for convenient measurement of double-sided phototherapy devices such as MTTS Firefly.

– touch screen liquid-crystal display (LCD)
– low battery
– 5 second result display time
– system failure
– out of measurement

– long battery life.
– standard AAA alkaline batteries are easy to replace.

Additional Features – available in 2022
– oxygen measurement
– flow measurement


Easy To Use

The Lightmeter features a large, clear display that makes it easy to read under all lighting conditions.



The Lighmeter is lightweight and portable. It can be carried around easily and helps health professionals to feel confident in the phototherapy treatment they provide to their patients.



The Lightmeter can be used to measure the intensity of any type of phototherapy device used for the treatment of hyperbilirubinemia in newborn babies, including single-sided and double-sided machines.

Technical Specifications

Dimensions and WeightHeight148mm
Performance SpecificationsApplicationLED and blue fluorescent phototherapy light sources.
Spectral Response400-520nm
Measurement Rangesingle0.1 – 150.0 μW/cm²/nm
double0.1 – 300.0 μW/cm²/nm
Resolution0.1 μW/cm²/nm
Cosine characteristics±2% @ 30 degree angle
±7% @ 60 degree angle
±25% @ 80 degree angle
Accuracy+/- 3% of reading
Battery SpecificationsType2xAA 1.5V Alkaline, Non-rechargeable
LifetimeUp to 120h operating time.
Display SpecificationsTypeTouch screen
Environmental SpecificationsOperating Temperature10°C to 40°C
Storage Temperature0°C to 50°C
Operation Humidity30 – 90% RH non condensing
Storage Humidity5 – 90% RH non condensing
Operation Atmospheric Pressure70 – 106 kPA
Storage Atmospheric Pressure70 – 106 kPA
Calibration ScheduleEvery 2 years, measured from delivery date.
Return to MTTS for calibration.
ServicingNo customer serviceable parts.

Standard warranty 1 year.

(Subject to MTTS policy)

Ordering Information and Servicing

Ordering InformationLightmeterLM-800Main Unit
Rechargeable batteries
and charger