摘要 |
This invention provides a calibration fixture that enables more accurate calibration of a touch probe on, for example, a CMM, with respect to the camera. The camera is mounted so that its optical axis is approximately or substantially parallel with the z-axis of the probe. The probe and workpiece are in relative motion, along a plane defined by orthogonal x and y axes, and optionally the z-axis and/or and rotation R about the z-axis. The calibration fixture is arranged to image from beneath the touch surface of the probe and, via a 180-degree prism structure, to transmit light from the probe touch point along the optical axis to the camera. Alternatively, two cameras respectively view the fiducial location relative to the CMM arm and the probe location when aligned on the fiducial. The fixture can define an integrated assembly with an optics block and a camera assembly. |