Interchangeable Chromatic Range Sensor Probe for a Coordinate Measuring Machine

摘要

An interchangeable chromatic range sensor (CRS) probe for a coordinate measuring machine (CMM). The CRS probe is capable of being automatically connected to a CMM under program control. In one embodiment, in order to make the CRS probe compatible with a standard CMM auto exchange joint, all CRS measurement light transmitting and receiving elements (e.g., the light source, wavelength detector, optical pen, etc.) are included in the CRS probe assembly. The CRS probe assembly also includes an auto exchange joint element that is attachable through a standard auto exchange joint connection to a CMM. In one embodiment, in order to provide the required signals through the limited number of connections of the standard CMM auto exchange joint (e.g., 13 pins), a low voltage differential signaling (LVDS) serializer may be utilized for providing additional control and data signals on two signal lines.

主权项

1. A chromatic range sensor (CRS) probe system capable of being automatically connected to a coordinate measuring machine (CMM) under program control, the CRS probe system comprising:
an auto exchange joint element that is attachable through a standard auto exchange joint connection to a CMM; and a CRS probe assembly that is mounted to the auto exchange joint element, for automatic connection to the CMM through the auto exchange joint element,wherein:
the CRS probe assembly comprises:
an optical pen comprising a confocal optical path including a chromatically dispersive optics portion, the optical pen configured to focus different wavelengths at different distances along a measurement axis proximate to a workpiece surface to be measured;an electrically powered light source which receives electrical power transmitted through the auto exchange joint element and generates light originating in the CRS probe assembly, the light comprising an input spectral profile of wavelengths routed to the optical pen; anda CRS wavelength detector comprising a spectrometer or spectrograph arrangement, wherein a dispersive optics portion transmits a spectral intensity profile to a detector array comprising a plurality of pixels distributed along a measurement axis of the CRS wavelength detector, the plurality of pixels receiving respective wavelengths and providing output spectral profile data; the CRS probe assembly is configured to receive power and control signals through the auto exchange joint connection; the CRS probe assembly is configured such that when the auto exchange joint element is attached to a CMM and the optical pen is operably positioned relative to a workpiece surface to perform measurement operations and the electrically powered light source generates the light, the optical pen inputs the input spectral profile, outputs corresponding radiation to the workpiece surface, receives reflected radiation from the workpiece surface, and outputs reflected radiation from the confocal optical path to provide an output spectral profile to the CRS wavelength detector, the output spectral profile comprising a distance-dependent profile component having a wavelength peak that indicates a measurement distance from the optical pen to the workpiece surface, and the CRS wavelength detector providing corresponding output spectral profile data; and the CRS probe assembly is configured to output measurement signals based on the output spectral profile data, the output measurement signals being indicative of a measurement distance to the workpiece surface.