Civil Engineering Professional Engineer Exam 2025 – 400 Free Practice Questions to Pass the Exam

The function of the electronic distance meter (EDM) in a Total Station is fundamentally reliant on the use of infrared light for measuring distances. Total Stations utilize this technology to emit a laser or infrared beam towards a target point. When the beam reflects off the target and returns to the instrument, the Total Station measures the time it took for the light to travel to the target and back. This time measurement is then converted into a distance calculation, making infrared light essential for the operation of the electronic distance meter.

While high-quality optics and battery power contribute to the overall performance and operability of the Total Station, they are not the primary elements responsible for distance measurement. Likewise, metallic reflectors can enhance the accuracy of the measurements by providing better reflection of the infrared light, but they are not essential for the EDM's basic function. Thus, infrared light is the critical component that enables the EDM to perform its central task of distance measurement effectively.