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Laser Flatness Measuring Instrument

High Precision accurate Measuring

Interferometric measuring instrument TOPOS is a tool that allows for two-dimensional and contactless flatness testing of the workpiece surfaces. Due to the four calibrated sensitivity settings of 0.5, 1, 2 and 4 μm per interference fringe, this instrument will not only be suitable for the measuring of reflective surfaces but in particular for fine-finished surfaces such as lapped surfaces. But, even with coarser grain, or for finish-ground surfaces.

Flatness Measuring Instrument Capabilities

The instrument can extend to a complete computer-aided measuring system for a two-dimensional determination of the surface shape. This happens by supplying a quantitative output and a varied graphic representation of the relevant results (picture). The graphics have the flexibility to print on to different printers. The absolute solute measuring accuracy is down to 0,1 μm. The measuring range is up to 100 μm. For your convenience, the automatic measuring procedures can be programmed and saved for future use. Measurements will save on the computer or drive for comparison with reference surfaces or for the determination of wear.

A laser flatness measuring instrument now permits contact-free flatness measuring with the accustomed quality of 0.3 microns stripe pattern. This now also permits testing of highly accurate, polished surfaces without contact. The test results shown on the video monitor can then be printed out and submitted as proof of quality. This clear advantage is now a necessity for QA (quality assurance).

In combination with computer evaluation, this clears the way for automation of the entire lapping and polishing process. In this case, handling systems transport the work-piece under the optical system, or from the optical system into the prepared packages.

Optical System used for Flatness measurement  of surfaces
Figure 68:
Evaluation of a phase pattern and three-dimensional representation of the measured surface.
Planarity error less than 2 microns