What are the key advantages of BK7/K9 optical glass?

Update Time:2026/4/28

BK7 and K9 optical glass are the most popular choices in the optical industry, thanks to a range of key advantages that make them suitable for countless applications worldwide.

First and foremost, they feature excellent optical clarity with a visible light transmittance of over 91%, which ensures that light passes through the material with minimal loss. This high transmittance is critical for applications such as camera lenses, microscope objectives, telescope eyepieces and other optical instruments, where clear and undistorted images are essential. Whether you are designing a consumer camera or a high-precision scientific instrument, BK7 and K9 optical glass can provide the optical clarity you need.

Second, BK7 and K9 optical glass have stable physical and chemical properties. They have a low thermal expansion coefficient, which means they do not expand or contract significantly with changes in temperature. This stability ensures consistent optical performance even in varying environmental conditions, making them suitable for both indoor and outdoor applications. They also have excellent chemical resistance, which protects them from corrosion and degradation caused by exposure to moisture, acids and other environmental factors. This durability ensures that your optical components will maintain their performance over a long service life.

Third, BK7 and K9 optical glass are highly machinable. They can be easily cut, ground, polished, drilled and coated to meet custom design requirements. This versatility allows manufacturers to produce a wide range of optical components, from simple flat windows and spherical lenses to precision prisms. Their good machinability also means that they can be produced in large quantities with consistent quality, making them a cost-effective choice for mass production projects.

Fourth, BK7 and K9 optical glass are cost-effective compared to other high-performance optical materials. While they offer excellent optical performance, they are more affordable than many specialized optical glasses, making them accessible to a wide range of applications, from consumer electronics to industrial equipment. This cost-effectiveness, combined with their reliable performance, makes them the preferred choice for many optical designers and manufacturers.

Finally, BK7 and K9 optical glass have a long history of use in the optical industry, which means their properties and performance are well understood and widely accepted. This established track record gives designers and manufacturers confidence in their suitability for various applications.

Our factory provides high-quality BK7 and K9 optical glass parts with customized processing services, including cutting, polishing, coating and CNC machining, to meet your specific application needs. Whether you need standard components or custom-designed optical parts, we can deliver products that meet your exact specifications.

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What is your MOQ for custom optical glass and display glass parts?: Felix Glass offers highly flexible MOQ to support client projects, including prototype testing, small batch trial orders and large-volume mass production. All products can be fully customized according to your drawings, tolerances and application standards. Send us your specs to get an accurate price quote within 24 hours.

Can I get free glass samples for testing before bulk order?: Yes, our FELIX GLASS factory supports sample testing for a wide range of precision optical glass components and assemblies. The lead time for sample production is 3 to 7 working days. Please contact us today to arrange samples and obtain a customized solution that meets your needs.

What is the production lead time for custom optical glass components?: What is the production lead time for custom optical glass components?
Answer: The lead time for standard samples is 3–7 business days, while mass production takes 15–25 business days, depending on product complexity and order volume. We provide reliable, rapid delivery for orders serving the industrial, medical, automotive, and aerospace sectors. Please submit your project details to receive an accurate delivery schedule.

Are your optical glass products ISO, CE and RoHS certified?: All FELIX GLASS precision optical glass components comply with ISO quality system standards, as well as CE and RoHS requirements. We provide comprehensive test reports, material certificates, and inspection documentation for customer review. Please feel free to request full certification details and a formal quotation today.

Do you offer one-stop custom optical glass processing services?: Yes. We provide a full range of in-house processing services, including CNC machining, precision grinding, optical polishing, vacuum coating (AR, AF, AG, IR), tempering, and screen printing. Every step—from raw material to finished product—is carried out within our own facility. Please let us know your requirements, and we will provide you with the most cost-effective solution.

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What are the key advantages of BK7/K9 optical glass?

A specialist in precision optical glass with 19 years of experience, providing comprehensive, satisfying custom solutions.

A specialist in precision optical glass with 19 years of experience, providing comprehensive, satisfying custom solutions.