Patent ID: 8792088
Filing Date: 2014-07-29
Classification: G01B,G01C,G01S

Abstract:
1. A distance-measuring system, comprising: a light source; a light detector; measuring optics for projecting light emitted by the light source to a target and for guiding light reflected from said target towards the light detector; a variable attenuator for adjusting intensity of light incident on the light detector, the variable attenuator comprising an attenuating filter arranged in a beam path between the measuring optics and the light detector, and an actuator coupled to the attenuating filter for moving the attenuating filter; and a controller; wherein along the same direction of movement of the attenuating filter caused by the actuator and within the beam path between the measuring optics and the light detector, the attenuating filter has first and second sections of varying transmissivity, a first section in which the transmissivity varies from higher transparency to lower transparency and a second section in which the transmissivity varies from higher transparency to lower transparency; and wherein the controller is adapted to take a decision on a kind of the target reflecting light towards the light detector, the kind of target comprising a target having low reflectivity and a target having high reflectivity, and to control the actuator in dependency on the kind of target such that the attenuating filter is either moved in a first direction of movement or in a second direction of movement opposite to the first direction of movement.