Electronic theodolites function in a manner that is very similar to optical theodolites and vernier transits. After the backsight has been set, they have zero-set buttons for rapid instrument orientation. Horizontal angles can be turned right and left, and repeat-angle averaging is available on a few models.
A very unique characteristic of electronic theodolites is that they have the ability to electronically be interfaced with data collectors and computer devices, allowing an instant, error-free field data transfer to the computer.
In earlier models of electronic theodolites, absolute methods were used for reading angles. They essentially were optical coincidence instruments, with photoelectric sensors being leveraged to read and scan circles.
In a nutshell, electronic theodolites consist of a telescope mounted on a base, and an electronic readout screen to display vertical and horizontal angles. These are convenient as this creates more accurate readings.
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