Patent ID: 7940378
Filing Date: 2011-05-10
Classification: G01S

Abstract:
1. A hand-held laser distance measuring device with pulse reflection mixing, comprising a control device ( 2 ) for calculating a distance (D) to a measurement object ( 3 ) over at least one determinable time difference (τ) between a measurement pulse ( 4 ) reflected at the measurement object ( 3 ) and a reference pulse ( 6 ) of an optically emitted transmitting pulse ( 7 ) traveling over a reference distance ( 5 ) within the device, the time difference (τ) being periodic with a pulse repetition frequency (f); a local oscillator ( 8 ) for generating the reference pulse ( 6 ) and a transmitting pulse ( 7 ) at the pulse repetition frequency (f), and for generating a scanning pulse ( 11 ) at the pulse repetition frequency (f) for scanning the measurement pulse ( 4 ) and the reference pulse ( 6 ); and at least one delay circuit ( 9 a , 9 b ) which can be controlled by the control device ( 2 ), is arranged between the local oscillator ( 8 ) and at least one of a light detector ( 10 ) and a light transmitter ( 12 ) for generating a variable delay between the scanning pulse ( 11 ) and the transmitting pulse ( 7 ) in order to scan the measurement pulse ( 4 ) and the reference pulse ( 6 ).