Contact Less (IR) Temperature Measurement for small rodents - The 153-IRB Thermometer was designed to measure cutaneous temperature of small rodents very fast and contact less. With the 153-IRB Thermometer, we especially focused on the optical dimension and the position of the IR sensor in order to allow measurements on very small surfaces without allowing the sensor to get wrong values with integration of environment temperature, which can be the case with other industrial type Infra red thermometers. This thermometer thus allows easy measurements even on mice tails - with high accuracy and repeatability. The cutaneous measurement should be correlated with usual rectal temperatures (see our RET-2 and 3 rectal probes for rodents). The 153-IRB thermometer is especially accurate on a temperature range from 25 to 40 °C and will prove to be useful for other lab applications as well. Infrared temperature, guidelines and important notice - Infrared temperature measurement consists in the detection of the quantity of light emitted by the measured object - the optical signal received by the sensor being then converted into an electrical signal. The instruments are equipped with a lens to concentrate the light on the sensor. This lenses have different characteristics according to the object you want to measure (diameter, focal length, viewing angle or distance ration between the surface "seen" by the lens and the distance to the object). Another parameter should be taken into account: the emissivity (or amount of emitted light) of the measured object. The focal specifications of typical general thermometers usually allow the measurement of objects from a minimum distance of 10 to 25 mm with a minimum target size of 15mm and a distance ratio of 1:10, the emissivity is generally fixed to 0,95. Such thermometers are therefore not able to measure from less than 10 mm from the object, and this measurement includes all points in a circle of 15 mm of diameter. If the object is situated 50cm away, the surface of measurement will have a diameter of 5 cm. Theses dimensions are fully inadequate for coetaneous temperature measurements in rodents... which is precisely the reason why we developed the 152-IRB Thermometer.