Patent ID: 7760337

Claim:
An optoelectronic distance measuring device, comprising: a frequency modulator which generates a high-frequency modulation signal; an emitter which emits a measuring beam to an object to be measured, the measuring beam being modulated by the high-frequency modulation signal; an avalanche photodiode which receives a reflected measuring beam reflected from the object and generates a corresponding high-frequency reflected measuring signal; a signal generating device which generates a high-frequency mixer signal, wherein the signal generating device is connected with the avalanche photodiode and the high-frequency mixer signal is transmitted to the avalanche photodiode and mixed with the high-frequency reflected measuring signal in the avalanche photodiode to provide a low-frequency measuring signal with the low-frequency measuring signal containing a phase information used for calculating the distance to be measured; and a signal processing device connected with said avalanche photodiode and used for determining the distance to be measured; wherein the frequency modulator is connected behind the avalanche photodiode and is also connected with said emitter.