Grade of Glass Roughness
Glass surface roughness is a system of standards for assessing and classifying glass surface roughness. Surface roughness is usually expressed by “Ra”value.The higher the Ra value, the rougher the glass surface; the lower the Ra value, the higher the smoothness of the glass surface.
Roughness is inversely proportional to gloss, the rougher the surface can increase light diffusion and reduce gloss. In the domestic common roughness unit for micron (um), commonly used parameters include Ra, Rz, Ry.
It directly affects the transparency, brightness, flatness and other properties of the glass, and is also an important parameter of AG glass. ( 7 important properties of AG glass )
Generally speaking, the smoother the glass surface, the better its optical performance and appearance. For AG(anti-glare) display cover glass that needs to meet certain appearance and functional requirements, its surface roughness standard is crucial.
Nowadays, glass is a common material that is widely used in electronic and electrical equipment, industrial control display equipment, display screens, optoelectronics, perovskite cells, solar photovoltaics and other fields. In the high-end optical field, it is becoming more and more important to judge the roughness of the glass surface.
At present, the international standards for glass surface roughness mainly include ISO, ASTM and other standards.These standards include the measurement method, unit, classification and other contents of roughness, as well as the roughness standards for different purposes. Customers should choose the appropriate standard according to their needs.
- In the process of glass production, if the surface roughness exceeds the standard requirements, it will lead to poor coating adhesion, affecting its service life and anti-corrosion performance.
- In the field of optics, if the surface roughness does not meet the standard, it will lead to a decrease in transmittance, affecting the application effect of glass in optical devices.
| Glass Surface Show | Roughness of Glass Surface(Ra) | Grade of Surface |
| Mirror Surface
| 0.006 | 15 |
| Matte mirror surface
| 0.012 | 14 |
| 14Mirror Glossy Surface
| 0.025 | 13 |
| Polished Glossy Surface
| 0.05 | 12 |
| Dark glossy surface
| 0.10 | 11 |
| Indiscernible direction of machining marks
| 0.20 | 10 |
| Slightly discernible direction of processing marks
| 0.40 | 9 |
| Distinguishable direction of processing marks
| 0.80 | 8 |
| Cannot see the direction of processing marks
| 1.60 | 7 |
| Slightly visible direction of processing marks
| 3.20 | 6 |
| Visible direction of machining marks
| 6.30 | 5 |
| Slightly visible knife marks
| 12.50 | 4 |
| Visible cutter marks
| 25 | 3 |
| Obviously visible cutter marks | 50 | 2 |
| 100 | 1 |
Our company has a strict control and management system for the surface roughness of glass to ensure that it meets the corresponding standard requirements. And there are related technical research and development and talent training to ensure that our glass meets international standards.
Tibbo Glass has been specialising in the production of toughened glass for over 20+ years, with toughening grades up to IK08/09/10. We specialise in the production of electrical and electronic glass, display cover glass, AG Glass, AR Glass, AF coated glass, ITO Coated Glass, FTO conductive glass and more.
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