Metrology at Mahr: Diversify

Mahr Federal Inc. knows the value of diversifying. The company, which provides dimensional measurement solutions, has a range of products on display this week at MD&M East, a medical device manufacturing trade show at the Jacob K. Javits Center in New York City.

The Providence, R.I.-based company is the US arm of Mahr GmbH, based in Göttingen, Germany. It offers both optical and tactile precision measurement systems, said Pat Nugent, vice president of metrology systems, adding that this makes the company unique; most others, he said, develop only tactile or only optical designs.

One Mahr Federal instrument on display at MD&M East is its MarSurf WS 1 surface metrology system, which uses white light interferometry, offers vertical resolution of 0.1 nm (0.004 µin.) and provides 3-D measurement in only a few seconds. The WS 1 can be configured to work both in the lab and on the shop floor.

The system’s white light optical sensor enables rapid, high-precision recording of surface topography on a wide range of materials. White light and a CCD camera allow the system to collect height information through the camera’s field of view. The camera simultaneously images both the test surface area and a high-precision reference surface built into the objective lens. The Mirau objective is moved in small steps in the Z direction during measurement, using a piezo positioner. The resultant interferograms are recorded as image stacks and converted into height data.

The WS 1 can be used in both precision inspection rooms and production environments, and on both reflective and rough workpieces. High vertical resolution allows surface roughness measurements on optical components such as lenses or mirrors with sub-µm accuracy. It also can measure the texture of micromechanical components made of virtually any material, including glass, paper, metal, plastic and various coated surfaces.

Dedicated topography software offers a wide range of functions, including many proposed 3-D parameters.

Mahr Federal meets the measurement needs of precision manufacturers in industries including automotive, defense, aerospace, job shops, machinery, bearings, pumps, engines, computers, can manufacturing, plastics and medical devices.

An engineer by training, Nugent said the wide variety of industries and applications that rely on Mahr Federal products is what keeps things interesting. And it helps keep the company afloat in troubled economic waters: Although the automotive sector is down, he said, the medical sector seems to be doing relatively well.

Laura S. Marshall
laura.marshall@laurin.com