Import Bk7 Ge Meniscus Lens Concave Convex Lens — Buy in wholesale FOB from Supplier in China

The Bk7 Ge meniscus lens is a concave-convex optical element manufactured from either N-BK7 optical glass or germanium, designed for infrared and visible spectrum applications. The lens features a positive focal length when the outer radius exceeds the inner radius, making it suitable for focusing or collimating light in thermal imaging and laser systems. Exact tolerances from the supplier include center thickness of ±0.05mm, adjustable to ±0.01mm for high-precision orders, and surface accuracy of λ/8, with capability to achieve λ/10. The outer diameter ranges from 3mm to 500mm with a tolerance of ±0.1mm, and effective aperture is maintained at 90% of the clear diameter.

N-BK7 is a standard borosilicate crown glass with low dispersion and high transmission in the visible range, while germanium is used for infrared wavelengths between 2μm and 14μm. The lens may be supplied uncoated or with an IR3 antireflection coating optimized for 3 - 5μm wavelengths. Surface quality is rated at 60/40 per MIL-O-13830, with the capability to deliver 10/5 for demanding applications. These materials and coatings are typical for precision optical systems in defense, medical diagnostics, and industrial sensing, where thermal stability and low scatter are critical.

This lens is commonly purchased by manufacturers of infrared cameras, spectroscopy instruments, and laser beam delivery systems. Buyers often require custom radii or coatings to match specific optical designs. The supplier offers small batch production with no minimum order quantity stated, and lead times are typically 2 - 4 weeks for standard configurations. Packaging is protective with individual foam inserts and sealed containers to prevent surface contamination. Trade terms are negotiable but commonly include FOB Shanghai or CIF destination ports.

Hanzhong Brisun Optics Co., Ltd. is a manufacturer based in Hantai District, Shaanxi Province, China, specializing in precision optical components including lenses, windows, prisms, and filters. The company operates a production facility with equipment capable of grinding, polishing, and coating optical elements in materials such as N-BK7, fused quartz, germanium, and calcium fluoride. Their listing indicates experience with custom orders and small batch production, but provides no verified certifications, employee count, or export history. Response rate and average response time are not tracked on their profile, indicating limited automated buyer engagement.

The supplier does not claim ISO certification, decades of operation, or partnerships with named global brands. Their strength lies in technical flexibility - offering tight tolerances on surface accuracy and center thickness, and the ability to apply IR3 coatings. They list thousands of stock items but do not provide catalog access or sample availability. Buyers should treat this as a direct manufacturer with limited digital presence, requiring direct communication for technical confirmation.