Surface Roughness Measuring Instruments
Various measurement tools are available in the market for analyzing 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 up to 0.04" |
< 10 μm < 0.39 Mil |
< a few mm < a few fractions of an inch |
< 7 mm < 0.28" |
| Measurable range | a few mm a few fractions of an inch |
1 to 200 μm 0.04 to 7.87 Mil |
40 μm to 15 mm 1.57 Mil to 0.59" |
15 μm to 2.7 mm 0.59 Mil to 0.11" |
| 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 |
