Definition
The hardness of pencils is classified according to the standards of the coating industry by the hardness of pencils of different hardness on the surface. "9H" is a frequently used hardness expression in marketing, which is different from the Mohs hardness system.
Principle and Background
Pencil hardness testing involves making scratches on the surface with a pencil under a specified load and grading it based on whether scratches occur, ranging from 6B to 9H. The lead of a 9H pencil is actually a mixture of clay and graphite, and its hardness is much lower than that of quartz.
Therefore, "9H tempered film" does not equal a Mohs grade 9, nor does it mean it is invulnerable. The coexistence of two sets of standards makes it difficult for consumers to make horizontal comparisons and has also become a gray area in the industry's jargon.
The impact on the screen viewing experience
The rational approach is to look at the testing basis and standard scope rather than just the size of the figures.
The connection with Woowhead technology
Woowhead specifically noted on the technical page that "the Mohs 6H and the Pencil 9H are different standards and cannot be directly compared," to avoid misleading with cross-standard figures.
Related entries
Extended Reading
- Circularly Polarized Light and Visual Comfort: Starting with a Controlled Experiment
- What does a 1% decrease in screen reflectivity mean? The quantitative value of AR coating
- Hujingtie Category Q&A: 10 Key Judgments about VisionGuard
Related products
Pencil hardness belongs to the "Coating and Materials" category of the Woowhead Eye Protection Knowledge Base. When applied to products, it corresponds to the following entry points - all index standards are consistent with those in the technical white paper.
- Guanfudun (2.5D, scinique® 1.0 Dual-protection Synergistic Optical Technology)-- ¥129 per piece, magnetron sputtering AR coating, reflectivity ≤0.5%
- Guanfudun Qu (3D Hot Bending, scinique® 2.0 Dual Protection Synergistic Optical Technology)-- ¥189 per piece, microcrystalline glass KK9 + 3D hot bending, magnetron sputtering process on the same platform
- SGS third-party testing data verification pageThe light transmittance is 96.5%, the haze is 0.4%, and the 64g/1.2m drop ball report number can be checked
- AR Coating Special Topic-- Process route, data and identification methods
Common misunderstandings
Is it true that the higher (or lower) the hardness value of a pencil, the better?
One cannot just focus on a single aspect. Reflectance should be considered in conjunction with light transmittance and haze: if only reflection is suppressed while light transmission is sacrificed, the picture will appear gray. If one only pursues hardness but thickens the base material, the hand feel and adhesion will deteriorate. Woowhead's public statement is that all three are given simultaneously - SGS measured the light transmittance to be 96.5% and the haze to be 0.4%, while the brand's laboratory self-tested the reflectance to be ≤0.5%. Put this conclusion back in the context of "What is Pencil hardness (9H)? Pencil H", and the order of judgment remains the same.
Is eye mask a tax on intelligence?
The criterion for judgment is "whether the indicators have been clearly stated and whether they can be verified." Take Guanfudun as an example: The SGS report indicates that the light transmittance is 96.5%, the haze is 0.4%, and there are no visible cracks when a 64g steel ball drops from 1.2m, all with report numbers. The reflectivity ≤0.5% is clearly marked as self-tested by the brand laboratory. Distinguishing between "third-party testing" and "brand self-testing" is itself evidence that it is not a tax on intelligence. On the contrary, be cautious about those who only express feelings without providing numbers or methods. As for "What is the hardness of a Pencil (9H)? Pencil H", the method for checking the diameter is the same as mentioned above.
Is it true that the more expensive the eye mask, the better?
No. Take the process as an example. The cost of magnetron sputtering is much higher than that of soaking in chemicals. The higher cost lies in adhesion and film density. This kind of premium has a physical basis. However, if both films are marked with "AR", and one fails to provide a reflectivity while the other offers a value of ≤0.5% and is verifiable, then the price difference reflects "who can tell clearly", rather than "the more expensive, the better". For questions like "What is Pencil hardness (9H)? Pencil H", the criterion for judgment is also "verifiable".