Patent ID: 7738083

Claim:
A distant measurement method applied for a distant measurement system, comprising the following steps: (a) emitting a first light beam and a second light beam from an emitting terminal, wherein the first light beam travels toward a target; (b) providing a switching sequence by a switch mechanism; (c) placing a receiving terminal to receive the first light beam reflected from the target and the second light beam in accordance with the switching sequence, and correspondingly to provide a first electrical signal and a second electrical signal; and (d) utilizing a controlling terminal to receive the first and second electrical signals, and calculating distance between the distant measurement system and the target in accordance with a phase differential formed between the first and second electrical signals; and wherein the step (a) further comprises providing a first frequency signal and a second frequency signal by an emitting terminal in accordance with a driving index transmitted from the controlling terminal; and wherein the receiving terminal receives the second frequency signal, and the second frequency signal is mixed with the first and second electrical signals, respectively.