N-BK7 (Schott AG) and H-K9L (CDGM, China) are borosilicate crown glasses widely used in precision optics. While their optical properties are nearly identical, their production standards and regional adoption differ.
Comparing Optical Glasses for Performance
Explore the differences between N-BK7 and H-K9L glasses.
Features | N-BK7 | H-K9L |
|---|---|---|
Refractive index | Stable refractive index for precision. | Similar index, good for medium precision. |
Optical clarity | High clarity, minimal distortion. | Good clarity for simpler applications. |
Transmission range | Over 92% light transmission. | High light transmission, less efficient. |
Thermal resistance | Handles temperature changes well. | Stable with moderate temperature shifts. |
Durability | More durable and wear-resistant. | Less durable, suitable for simpler tasks. |
Cost | Higher cost due to quality. | Lower cost, budget-friendly option. |
Applications | Used in high-precision systems. | Ideal for cost-effective components. |
Quality control | Stricter quality checks ensure reliability. | Less strict quality control. |
When picking materials for optical uses, you may see N-BK7 and H-K9L. These glasses are alike but have important differences. N-BK7 is known for its high quality and great performance. H-K9L, however, is cheaper and works well for simpler needs. Knowing how H-K9L and N-BK7 differ helps you choose the right one. Whether you need accuracy or to save money, both are useful in optics.
A 2024 study in Micromachines highlighted N-BK7’s superior thermal stability in high-power laser systems, while noting H-K9L’s growing popularity in consumer optics due to its RoHS compliance and lower production costs.
Key Takeaways
N-BK7 has great optical quality and works well for tools like microscopes and telescopes.
H-K9L is cheaper and good for simpler optical tasks without losing much quality.
Pick N-BK7 for projects needing accuracy and strength, especially in tough environments.
H-K9L is best for low-cost projects like making basic camera lenses.
Both materials handle heat similarly, but N-BK7 is stronger in extreme conditions.
N-BK7 lets over 92% of light pass through, making it great for high-quality optical tools.
When choosing, think about your budget and how well the material needs to perform.
Knowing the differences between N-BK7 and H-K9L helps you pick the right one for your project.
Overview of N-BK7
Key Properties of N-BK7
Refractive index and optical clarity
As a researcher, you should know N-BK7 is a top-notch glass with great clarity. Its refractive index changes very little, staying under 5×10⁻⁶. This ensures it works well in precise optical systems. It has an Abbe number of 64.17, reducing color distortion. This improves image quality, making it perfect for demanding optical tasks.
Transmission range and wavelength performance
N-BK7 lets over 92% of light pass through in visible and near-infrared ranges. This wide range makes it useful for lasers, cameras, and other optical tools. It performs well across many wavelengths, making it flexible for science and industry.
Thermal properties and resistance to temperature changes
N-BK7 has a thermal expansion rate of 7.1 × 10⁻⁶/K at 20°C. This means it handles temperature changes without losing its optical features. It stays strong under heat, making it great for precise systems in tough conditions.
Common Optical Applications of N-BK7
Use in lenses, prisms, and optical windows
N-BK7 is often used in lenses, prisms, and windows. Its clarity and accuracy make it ideal for these parts. For example, it helps create sharp images in camera lenses. In prisms, it bends light accurately. Its strength makes it a good choice for optical windows.
Applications in high-precision optical systems
N-BK7 is key in precise optical tools like microscopes and telescopes. It’s also used in medical imaging and aerospace equipment. Its steady performance makes it reliable for many uses.
In a 2025 industrial report, N-BK7 demonstrated <0.1% wavefront distortion in ZYGO-tested hemispherical dome lenses for video cameras, validating its use in high-resolution imaging.
Application Area | Usage Rate Description |
|---|---|
Cameras | Creates clear, high-quality images |
Microscopes | Important for clear optical results |
Telescopes | Helps produce sharp, detailed images |
Medical Imaging | Needed for accurate imaging parts |
Semiconductor Manufacturing | Used in making chips and inspecting wafers |
Aerospace and Defense | Used in targeting and surveillance tools |
Advantages and Limitations of N-BK7
Advantages: High optical quality, durability, and versatility
N-BK7 is known for its great quality and strength. Special coatings and careful production keep its performance steady. It works in many fields, from science to factories. Its use is growing in medical and aerospace areas.
Limitations: Higher cost compared to alternatives
N-BK7 costs more than cheaper options like H-K9L. This makes it less ideal for projects with tight budgets. But its high quality and dependability often make it worth the price for precise tasks.
Overview of H-K9L Glass
Key Properties of H-K9L Glass
Refractive index and optical clarity
H-K9L glass has a refractive index of 1.5168. This is close to N-BK7’s index. It provides good clarity for most uses. Its Abbe number is 64.06, reducing color issues. This makes it good for systems needing medium precision. H-K9L works well in simpler environments. It is chinese equivalent to N-Bk7.
Transmission range and wavelength performance
H-K9L passes light in visible and near-infrared ranges. It allows high amounts of light through. This is important for cameras and detectors. Its ability to save money makes it useful for many projects.
Thermal properties and resistance to temperature changes
H-K9L glass handles heat changes well. Its thermal expansion rate is 7.1 × 10⁻⁶/K. It stays stable with moderate temperature shifts. This makes it reliable in changing environments.
Common Applications of H-K9L
A 2024 survey of Chinese OEMs revealed H-K9L’s cost-effectiveness in smartphone camera modules, though some noted N-BK7’s edge in high-precision lithography lenses.
Dr. Li Wei (Guangxi University of Science and Technology) advises N-BK7 for UV-near IR laser systems requiring <1/4λ flatness, while H-K9L suffices for consumer optics and budget-conscious projects.
Use in cost-effective optical components
H-K9L is great for budget-friendly projects. It is strong and lets in lots of light. It is used for:
Protecting detectors from damage.
Keeping cameras safe from outside harm.
Applications in less demanding optical systems
H-K9L is used in systems needing less precision. These include lasers, simple cameras, and factory tools. Its mix of quality and price makes it a smart choice.
Advantages and Limitations of H-K9L
Advantages: Lower cost, similar optical performance to N-BK7
H-K9L costs less than N-BK7 but works similarly. It has good clarity and reduces color problems. This makes it a favorite for low-budget projects.
Limitations: Slightly lower quality control and durability
H-K9L is less durable than N-BK7. Its quality checks are not as strict. But for simpler uses, these differences don’t matter much.
Direct Comparison of N-BK7 vs H-K9L
Optical Performance
Clarity and index of refraction comparison
Both N-BK7 and H-K9L glass are clear and reliable. BK7 stays very stable, even in changing conditions. Its refractive index is 1.5168, which keeps images sharp. This makes it great for precise optical tools. H-K9L also has a refractive index of 1.5168 and offers good clarity. However, BK7 is made with stricter quality checks. This gives it better and more consistent optical performance.
Transmission range and wavelength suitability
N-BK7 lets over 92% of light pass through visible and near-infrared ranges. This makes it perfect for lasers and imaging devices needing high accuracy. H-K9L also works well in these ranges but is slightly less efficient. It’s a good choice for projects that don’t need extreme precision. For lasers or high-performance needs, N-BK7 is the better pick.
Durability and Thermal Resistance
Resistance to temperature fluctuations
N-BK7 handles temperature changes very well. Its low thermal expansion rate of 7.1 × 10⁻⁶/K keeps its optical features steady. H-K9L has similar thermal properties and works fine with moderate temperature shifts. But N-BK7’s better surface and material make it stronger in tough conditions.
Longevity and wear resistance
N-BK7 lasts longer and resists wear better. Its polished surface and strong material make it ideal for heavy use in precise systems. H-K9L is durable too but may wear out faster. For simpler tasks, H-K9L is a good and affordable option.
Cost and Availability
Price differences and budget considerations
Price is a big factor when choosing between these glasses. N-BK7 costs more because of its high quality and strict production. H-K9L is cheaper but still performs well for most uses. If you’re on a tight budget, H-K9L is a smart choice.
Global availability and sourcing
Both glasses are easy to find worldwide. N-BK7 is made by top companies and used in high-end tools. H-K9L, made in China, is popular for budget-friendly projects. Both are available, but N-BK7 may cost more to source.
Suitability for Specific Applications
High-precision optical systems
For high-precision systems, materials must perform well and stay reliable. N-BK7 is the top choice for these needs. Its clear optics and steady index of refraction ensure accurate light flow. This makes it perfect for microscopes, telescopes, and advanced imaging tools. N-BK7 helps create sharp images with little distortion.
H-K9L has good optical features but isn’t ideal for precise tasks. Its lower durability and quality checks suit simpler uses better. For sensitive tools or projects needing high accuracy, N-BK7 is the dependable option.
Tip: Use N-BK7 for medical imaging or aerospace optics. It works well in tough conditions and ensures steady performance.
Cost-sensitive projects and industries
For projects on a budget, H-K9L is a great pick. It’s affordable and still performs well optically. Industries like manufacturing and consumer electronics benefit from its cost-effectiveness. H-K9L is good for tasks like protective windows or basic camera lenses.
N-BK7 costs more due to its high quality and strict production. It’s not the best choice for tight budgets. If your project doesn’t need top-level optics, H-K9L offers good value without losing much quality.
Note: For large-scale or budget-limited projects, H-K9L balances cost and performance. It’s a smart option for many industries.
How to Choose Between N-BK7 and H-K9L
Factors to Consider
Budget constraints and cost-effectiveness
Your budget is important when picking between N-BK7 and H-K9L. If you need good optical parts but have less money, H-K9L is a smart choice. It works well for simpler tasks and saves money. N-BK7 costs more but gives better quality and reliability. It’s best for projects needing high precision and dependability.
Think about your project size when comparing costs. For big projects or industries needing savings, H-K9L can cut costs while still working fine. But for precise systems, spending more on N-BK7 is worth it for its durability and clarity.
Performance requirements and environmental conditions
Your project’s needs should help you decide. N-BK7 is great for tasks needing clear optics and steady performance. Its ability to reduce color issues makes it perfect for advanced imaging tools. For example, N-BK7 creates sharp, clear images in lenses.
H-K9L is less advanced but works well in normal conditions. It’s good for tasks not needing extreme accuracy. For instance, using H-K9L in less important lens parts saves money but still works okay. However, in tough conditions or with big temperature changes, N-BK7’s strength and heat resistance are better.
N-BK7 and H-K9L are great for optical uses. They work well but suit different needs. N-BK7 is better for high-precision tasks. It has top-notch quality and lasts longer. H-K9L is cheaper and works fine for simpler jobs. It saves money without losing much performance.
Key Takeaway: Pick N-BK7 for precise tools needing accuracy and strength. Choose H-K9L if saving money matters more and exact precision isn’t needed.
Knowing their features helps you pick the right one for your project.
FAQ
What is the main difference between N-BK7 and H-K9L?
N-BK7 is stronger and clearer, great for precise tasks. H-K9L costs less and works well for simpler projects.
Which glass is better for high-precision optical systems?
N-BK7 is best for precise tools like microscopes and telescopes. Its clear optics and steady performance make it reliable.
Can H-K9L replace N-BK7 in all applications?
H-K9L can work for cheaper projects but not for precise ones. It’s less durable and doesn’t handle tough conditions as well.
How do the thermal properties of N-BK7 and H-K9L compare?
Both glasses handle heat changes similarly. But N-BK7 is stronger and better for extreme conditions.
Is N-BK7 worth the higher cost?
If you need accuracy and strength, N-BK7 is worth it. For simple tasks, H-K9L saves money and still works fine.
Which glass is more suitable for budget-sensitive projects?
H-K9L is better for saving money. It’s good for basic uses in factories and electronics.
Are N-BK7 and H-K9L globally available?
Yes, both are easy to find. N-BK7 is made worldwide, while H-K9L is mostly made in China.
How do the engineer choose between N-BK7 and H-K9L for my project?
Think about your budget and needs. Pick N-BK7 for precision and strength. Choose H-K9L if saving money matters more.
