λ4-λ N-BK7 Plano-concave Lenses
High Optical Quality:
The λ4 surface accuracy ensures precision optical performance, minimizing wavefront distortions and optical aberrations.
The 40-20 scratch-dig surface quality guarantees excellent surface smoothness, reducing scattering and unwanted diffraction effects.
Broad Wavelength Range:
These lenses are typically designed for operation across a wide wavelength range, although the exact range may vary depending on the coating and intended application. N-BK7 glass itself has a transmission range from 350 nm to 2.0 μm (uncoated), making it suitable for both visible and near-infrared applications.
Material Properties:
N-BK7 is a high-quality borosilicate crown glass known for its excellent homogeneity, low bubble and inclusion content, and ease of manufacturing.
It offers a good balance of transmission, durability, and cost-effectiveness, making it a popular choice for many optical components.
Focal Length and Diverging Ability:
Plano-concave lenses have a negative focal length, enabling them to diverge collimated beams. This property makes them useful in applications where beam expansion or divergence is required.
Versatility:
Available in various diameters, including 6 mm, 9 mm, 1/2″, 25 mm, 1″, and 2″, allowing for flexibility in system design.
Focal lengths can also vary widely, offering a range of options to suit different applications.
Antireflection Coatings:
While the exact coating specifications may not be directly stated as “λ4-λ” in the context of this question, N-BK7 plano-concave lenses can be coated with various antireflection (AR) coatings to minimize reflections and maximize transmission over specific wavelength ranges. This can improve overall optical efficiency.
Applications: Laser Scanners, Remote Sensing Instruments, Imaging Instruments, Fiber Lasers, Interferometers, etc.