Photo-Meters "LX" is a precision meter required for scientific and laboratory work. This model utilizes filtered sensors with spectral response tightly calibrated to the C.I.E. Photopic response. The illuminance receptors closely follow the Cosine Law relative sensitivity versus angle of illuminance.

Photo-Meters are simple to operate. Press the Measure button to get continuously updated readings. Releasing the Measure button freezes the last reading for convenient reference. The Range button adjusts the measurement display for the resolution desired.

The LED display is visible in very dim light, as well as direct sunlight. LED displays are inherently robust in comparison to LCD (liquid crystal) displays. Commonly available batteries power Photo-Meters for tens of thousands of readings.