Surface Roughness Measuring Instruments
Measuring instruments of various workings are available on market for analysing and evaluating surface roughness and shape.
This section introduces the principles and characteristics of typical contact-type measuring instruments (surface roughness tester and atomic force microscope) and non-contact type measuring instruments (white light interferometer and laser scanning microscope).
| Method | Contact type | Non-contact type | ||
|---|---|---|---|---|
| Measuring instrument | Contact-type roughness tester |
Atomic force microscope (AFM) |
White light interferometer |
Laser microscope |
| Measurement resolution | 1nm | < 0.01 nm | < 0.1 nm | 0.1nm |
| Height measurement range | up to 1 mm | < 10 μm | < a few mm | < 7 mm |
| Measurable range | a few mm | 1 to 200 μm | 40 μm to 15 mm | 15 μm to 2.7 mm |
| Angular characteristic | – | Poor | Fair | Good |
| Data resolution | – | VGA | VGA | SXGA |
| Measurement site positioning | – | Optional | Built-in optical camera | Built-in optical camera |
| Damage to samples | Contact | Contact | Non-contact | Non-contact |
