It’s becoming common to refer to the devices used for dimensional and coordinate measurement—vision/optics, lasers, touch probes, and others—as sensors. Multisensor measuring systems use two or more of these devices. It can be confusing because none of these “sensors” is actually a sensor. The sensing is done elsewhere.

Categories of sensors
Sensors used for dimensional measurement are usually categorized as contact or noncontact. Touch probes do just that—they touch (contact) the part to register a data point. Noncontact sensors use a variety of technologies that typically involve optical imaging. New sensor types are actually variations of the two categories. For example, a newer type of microsensing probe gets close to contacting the surface like a touch probe, but registers a point with virtually no surface contact.

Yes, there are other sensor technologies used for measurement such as eddy current, capacitance, ultrasonics, and x-rays that are noncontact. However, they’re typically not used for dimensional measurement, measuring other characteristics of parts instead.

Touch triggering

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