Patent ID: 7900369
Filing Date: 2011-03-08
Classification: G01B

Abstract:
1. An electric measuring tape comprising an external housing provided with a tape exit opening, comprising: a tape winding-up device, a tape wound up in the tape winding-up device and withdrawable from the external housing through the tape exit opening, the tape having a first surface and a second surface, a radiation source arranged between the tape exit opening and the tape Winding-up device, for sending a beam onto the first surface of the tape, and a detector assembly placed at the side of the second surface of the tape, for receiving the beam and outputting data representing the received radiation to an evaluation device for determining the length of the tape extracted through the tape exit opening, wherein the tape is radiation-permeable and is provided with a biunique code on one of the two surfaces thereof, the code representing the length of the tape extracted through the tape exit opening and comprising elements which influence the radiation-transmitting capacity of the tape, and wherein the detector assembly is configured to determine the length of the tape extracted without continuous activation of the radiation source.