Patent ID: 7019522

Claim:
An apparatus for measuring a magnetic field produced by an insertion device comprising: (a) a magnetic field strength sensor, wherein the sensor produces an output signal; (b) a first stage for positioning the sensor along a first axis of the insertion device, wherein: (i) the first stage comprises: (a) a first stage carriage, (b) first stage guide means comprising a first end and a second end, (c) a first stage motor, (d) a first stage drive mechanism, and (e) first stage position-sensing means, and (ii) the first stage guide means is mounted on the insertion device, wherein: (f) the axis of the first stage guide means is parallel with the first axis, and (g) the first axis is the long axis of the insertion device; (c) means for controlling position of the first stage; (d) a second stage for positioning the sensor along a second axis of the insertion device, wherein: (i) the second stage comprises: (a) a second stage carriage, (b) second stage guide means, (c) a second stage motor, (d) a second stage drive mechanism, and (e) second stage position-sensing means, (ii) the second axis is perpendicular to the first axis, and (iii) the second stage is mounted on the first stage; (e) means for controlling position of the second stage; (f) a third stage for positioning the sensor along a third axis of the insertion device, wherein: (i) the third stage comprises: (a) a third stage carriage, (b) third stage guide means, (c) a third stage motor, (d) a third stage drive mechanism, and (e) third stage position-sensing means, (ii) the third axis is perpendicular to the first axis and to the second axis; (iii) the third stage is mounted on the second stage, and (iv) the sensor is mounted on the third stage; (g) means for controlling position of the third stage; and (h) information storage means for reading the output signal from the sensor operably connected to the sensor.