Measurement and testing

Precise measurements are indispensable for the quality testing of incoming and outgoing products - both for series components as well as for prototypical test specimens from development. Targeted analyses and improvements in the production process also require continuous precise measurement results.

Whether a testing task can be solved with a special measuring principle depends on the geometry of the part, its material properties as well as external boundary conditions, which have to be analyzed in detail. The interpretation of the obtained data and its evaluation also present different challenges, depending on the application. As part of our research assignment for small and medium-sized companies, we provide recommendations for decisions regarding the selection of measuring equipment for quality assurance in production.

In addition, we carry out individual measurements including data evaluation, logging and feasibility studies. The Fraunhofer IPT has numerous measuring instruments for the characterization of components with dimensions from the metre to the nanometre range at its disposal. Our specialties are high-precision multisensory 3D geometry measurement, submicrometric surface measurements, e.g. for roughness analysis, and optical inspections.

Components with dimensions down to the metre range can be fully measured using various optical and tactile form measurement methods. Applications of the various measurement methods:

• Multisensor CMM with high-resolution image processing, measuring, tactile probe, non-contact confocal chromatic sensor, micro-fiber probe for smallest cavities (Werth VideoCheck UA)
• Coordinate measuring machine Zeiss PRISMO with turntable for measuring difficult to access components
• Formtester for roundness measurement with tactile and fibre-optic sensor (Mahr Formtester MMQ 400)
• 3D capturing of lenses and mould inserts (Mahr Aspheric LD260)
  
• Digitization of small and large objects with fringe projection (Steinbichler COMET 5 11Ma with rotary table). Measuring ranges from 70 x 50 x 50 mm³ to 900 x 600 x 600 mm³.

Optical measuring methods provide the ability to detect surface structures, whereas tactile systems reach their limits. Applications of the various measurement methods:

• 3D Nano measuring system with focus sensor and AFM sensor head (Sios NMM-1)
• White light interferometer with various magnifications and lenses (Bruker NPFlex)
• Spot chromatic sensor on measuring portal (FRT MicroProf)
• Scanning electron microscope with software for 3D surface acquisition (Zeiss NEON ESB with Alicona-MeX3D software)
• Confocal microscope Nanofocus µsurf custom
• Focus Variation Sensors Alicona IF-Sensor R25
• Optical coherence tomography OCT (Thorlabs Telesto and various proprietary developments)

The characterization of optically functional components is a major challenge regarding the measurement accuracy. For this purpose we primarily rely on te following interferometric devices:

• 6" form test interferometer (Zygo VeriFire AT+)
• Mobile micro interferometer (FisBa µPhase DCI2 HR)
• Wavefront measuring device (Trioptics WaveMaster LAB)
• Phase measuring deflectometry for free-form surface measurement (3D-Shape SpecGage3D)
• Stylus writer (Taylor-Hobson GPI 1250)