A Glossary of Metrology.

mardi, août 28, 2018

Title: A Glossary of Metrology

Publish date: 28/8/2018



When you place an order for precision measurement sensors with Solartron Metrology or you use any of our measuring system solutions, we want you to fully understand every part of the quality service you receive.

As you are probably aware, precision measuring systems is a sector with its own technical vocabulary, which for most people is not easy to understand.

To help you better understand what we do at Solartron and what we are doing for your business, we have compiled this glossary of metrology terminology:


The accuracy of all Solartron l measurement sensors is stated as “% of reading”. We use this format because. clearly shows the exceptional performance of the sensors.

Block gauge

Block gauges are typically used for precision measurements in circumstances where space and access is limited, and where the use of axial probes is not possible due to body length. Internal dimensions of bores and cavities are often measured using block gauges.

Displacement sensor

Analogue and digital displacement sensors, also referred to as displacement gauges, are contact measurement devices used to compare the position of an object with its reference position, and measure any difference between the two. Typical measurements are an object’s height, thickness and width.

Feather-touch gauging probe

Feather-touch gauging probes provide low, repeatable tip forces and are designed to gauge delicate surfaces, such as car windscreens, flat screen TV components, pharmaceutical bottles, electro-mechanical components and plastic parts.

Gauging probe

Analogue and digital gauging probes are devices used to quickly and efficiently measure object parameters. Examples include conventional pencil-style gauging probes, feather-touch probes and ultra-feather-touch probes.


Hysteresis is the difference between measurements when readings are taken from opposite directions.

Lever probe

Typically, lever probes are used for precision gauging of components for profiling. The narrow body of the lever probe, combined with its gentle tip force, allows it to access hard-to-reach details on fragile components.

Linear variable differential transformer

This is an electrical transformer used for measuring linear displacement. Put simply, a linear variable differential transformer, or LVDT, is a sensor used to measure position.


Linearity is the deviation of a transducer's response from a straight line. Solartron uses two definitions for linearity depending on product type. These are “% FRO” and “% of reading” (0.5% reading approximately equals 0.25% FRO). 

Measurement range

This refers to the range of displacement over which measured values are within the maximum permissible errors of the measurement sensor. For analogue products, this is expressed as a displacement either side of the zero or null position (usually the midpoint of the probes movement). For digital products, this is expressed as a single displacement from the start of the measurement range to the end position.


This is the science of measurement. In the manufacturing sector, the term refers to the technology used by companies to carry out the quality assurance processes that ensure every product functions how it should.

Non-contact sensor

Non-contact measurement sensors are used for applications for which a contact gauging device is not appropriate. These precision measurement devices are commonly used in manufacturing sectors such as the automotive, medical and aerospace industries.

Optical linear encoders

Optical linear encoders are used in combination with scales to measure position (and also velocity and motion). These digital devices, typically employed as part of digital measuring system solution, are used when a high degree of precision measurement is required.

Tip force

The tip force is the force applied by a gauging probe on the object being measured. Feather-touch and ultra-feather-touch gauging probes provide low, repeatable tip forces and are designed to measure fragile surfaces.

Total mechanical range

This is the distance over which the moving part of a transducer can be placed between two physical end stops. Total mechanical range is always greater than measuring range.

Wireless sensor

This is a measurement sensor that can collect data from process control instruments without the need for cables. By using a wireless sensor, the gauging process is not restricted by cable length and routing, or the risk of cable damage.

Wireless sensor network

A wireless sensor network comprises a number of autonomous wireless measurement devices and a secure gateway, through which the measurement data from the devices are fed to dedicated computers or programmable logic controllers.

Still can’t find what you’re looking for?

Want to know more about what Solartron Metrology can do for your business?

Contact us on +44 (0)1243 833333 or sales.solartronmetrology@ametek.com