Introduction
Sapphire glass is widely used in precision optical and electronic applications due to its high hardness, scratch resistance, and optical clarity. However, uncoated sapphire reflects a significant portion of visible light and is prone to fingerprint and oil contamination. To address these challenges, Sunyincrystal Industrial (Shenzhen) Co., Ltd. applies advanced AR (anti-reflection) and AF (anti-fingerprint) surface treatment technologies to sapphire components. With 31 years of sapphire manufacturing experience and integrated in-house capabilities from crystal growth to final coating, Sunyincrystal provides high-performance coated sapphire products for B2B customers worldwide.
What Is AR Coating for Sapphire?
AR coating, or anti-reflection coating, is a multilayer optical thin film deposited on the sapphire surface. It uses alternating layers of high- and low-refractive-index materials such as tantalum pentoxide, titanium dioxide, magnesium oxide, and silicon dioxide. Through optical interference effects, AR coating reduces surface reflection and increases light transmission.
Technical reference data:
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Bare sapphire cover plates typically achieve average transmittance of 84%–86% in the visible spectrum (380 nm–780 nm).
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After single-side AR coating, transmittance reaches no less than 89%.
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After double-side AR coating, transmittance reaches no less than 95%.
These values make AR-coated sapphire particularly suitable for applications requiring high optical clarity and low reflection.
What Is AF Coating for Sapphire?
AF coating, or anti-fingerprint coating, is a nano-scale hydrophobic and oleophobic layer applied to the sapphire surface. Based on the lotus leaf effect, it reduces surface tension so that fingerprints, oil, and stains do not easily adhere and can be wiped off easily. AF coating provides water, oil, stain, and sweat repellency.
Sunyincrystal uses Japanese Daikin and Shin-Etsu source materials for AF coating, combined with a Korean Hanil vacuum coating machine and a US Veeco hollow cathode ion source. This equipment configuration supports the production of high-performance AF-coated sapphire products with excellent durability.
Combined AR and AF Coating Solution
In many B2B applications, AR and AF coatings are used together. AR coating is deposited directly on the sapphire surface to improve transmittance and reduce reflection. AF coating is then applied on top of the AR coating to provide anti-fingerprint and easy-cleaning properties. This combination delivers both optical and functional benefits in a single coated sapphire component.
Coating Equipment and Process Capabilities
Sunyincrystal operates two specialized coating lines to meet different production requirements:
Japanese Showa Optical Coating Machine
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High-temperature capability of 380°C–420°C.
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Dual monitoring system using quartz crystal control and optical control for precise film thickness.
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Dual assisted ion sources for enhanced film density and adhesion.
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Suitable for high-precision multilayer AR coating stacks.
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Produces coatings with high hardness and high oxidation resistance.
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Stable high-vacuum performance and high yield.
Hanil Coating Machine HVC-1600
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Large vacuum chamber suitable for large-size cover plates and other products.
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Equipped with a Veeco ion source.
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Capable of AR, AF, and combined AR+AF coating processes.
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Stable high-vacuum performance for consistent production.
This dual-line configuration allows Sunyincrystal to serve both high-mix, low-volume precision orders and high-volume mass production needs.
AF Coating Durability Data
AF coating durability is a critical factor for B2B buyers. Sunyincrystal verifies AF performance through steel wool abrasion testing under a 1 kg load. The measured water contact angle results are as follows:
| Test Condition | Water Contact Angle |
|---|---|
| Initial | ≥115° |
| 3,000 cycles | ≥110° |
| 5,000 cycles | ≥107° |
| 8,000 cycles | ≥105° |
| 10,000 cycles | ≥104° |
| 15,000 cycles | ≥100° |
These results demonstrate the long-lasting hydrophobic performance of Sunyincrystal AF coatings under repeated mechanical abrasion.
Typical B2B Applications
AR and AF coated sapphire products from Sunyincrystal are used in a wide range of industrial and consumer applications:
AR-Coated Sapphire Applications
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Smartwatch crystals and smart wearable covers
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Mobile phone camera lens covers
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Sapphire windows and optical windows
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High-transmittance optical components
AF-Coated Sapphire Applications
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Mobile phone covers
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Touch screens
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Smart wearables
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Endoscope protective windows
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Display covers requiring easy cleaning
Quality Control and Testing
Sunyincrystal maintains strict quality control throughout the coating process:
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Film thickness control: quartz crystal oscillation method enables real-time monitoring of film thickness.
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Pre-coating treatment: ion source cleaning is performed to improve coating adhesion.
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Testing capabilities: water contact angle meter, spectrophotometer for transmittance and reflectance measurement, pencil hardness testing, Mohs hardness testing, eraser abrasion testing, steel wool abrasion testing, and other wear tests.
Certifications and Compliance
Sunyincrystal is certified under:
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ISO 9001 quality management system (since 2008)
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REACH certification
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RoHS certification
These certifications support compliance with international B2B procurement requirements.
Why Choose Sunyincrystal for AR and AF Coated Sapphire?
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Integrated supply chain: from sapphire crystal growth to screen printing, electroplating, and coating.
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Proven coating expertise: Japanese Showa equipment for precision AR coatings and Korean Hanil equipment for large-size AF coatings.
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Verified performance data: clear transmittance and water contact angle results for technical evaluation.
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Flexible production capacity: dual-line setup supports both custom precision orders and large-scale manufacturing.
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Industry experience: 31 years in sapphire R&D and production, and one of the drafting units of China’s synthetic sapphire glass industry standard.
Frequently Asked Questions
What is the transmittance of AR-coated sapphire?
Single-side AR coating achieves no less than 89% transmittance, and double-side AR coating achieves no less than 95% transmittance in the visible spectrum.
How durable is Sunyincrystal AF coating?
After 15,000 cycles of steel wool abrasion under a 1 kg load, the water contact angle remains at or above 100°.
Can AR and AF coatings be combined on the same sapphire part?
Yes, Sunyincrystal provides combined AR+AF coating services, with AF applied on top of the AR layer.
What equipment does Sunyincrystal use for coating?
The company uses Japanese Showa optical coating machines for precision AR coatings and a Korean Hanil HVC-1600 machine for large-size AF and AR+AF coatings.
Is Sunyincrystal certified for international supply?
Yes, the company holds ISO 9001, REACH, and RoHS certifications.
For B2B inquiries about AR and AF coated sapphire products, please contact Sunyincrystal Industrial (Shenzhen) Co., Ltd. with your technical specifications and volume requirements.
SUN YIN CRYSTAL
