λ4-λ N-BK7 Plano-convex Lenses

A Plano-convex (PCX) lens is an optical lens featuring one plane face and one convex face, designed with a positive focal length. These lenses are ideal for various optical applications, such as collecting and focusing collimated light, collimating light from a point source, or reducing the focal length of a lens group. Compared to Biconvex lenses, Plano-convex lenses, with their asymmetrical design, perform best for an infinite absolute conjugate ratio (objective distance: image distance). However, they still effectively minimize spherical aberrations for absolute conjugate ratios greater than 5:1. For conjugate ratios below 5:1, using plano-convex lenses in pairs or opting for a biconvex lens is recommended.

N-BK7 glass is a RoHS-compliant borosilicate material commonly used in the visible and NIR spectrum. It is widely utilized for manufacturing precision visible components due to its high optical homogeneity, excellent scratch and abrasion resistance, low cost, and low inclusion content. N-BK7 is an ideal substitute for UV Fused Silica when high UV transmission is not required and a preferred alternative for CaF2 in the 1.65-2.3 micron wavelength region, given its lower manufacturing costs.

Specifications:

Lens Form	Plano-convex Lens
Material	N-BK7
Diameters(mm)	0.5-300mm
Design Wavelength	587.6nm
Coating	Uncoated/BBAR
Surface Quality (S/D)	40/20
Irregularity@632.8nm	λ/4-λ
Centering Error	≤2 arc min
Clear Aperture	90%
Protective Chamfer	0.2mmx45°
Diameter Tolerance	+0/-0.1mm
Thickness Tolerance	+/-0.1mm

 

Features:

• High Optical Homogeneity: N-BK7 glass offers excellent optical clarity and uniformity, ensuring consistent performance and minimal image distortion.
• Broad Transmission Range: These lenses provide good transmission in the visible and near-infrared (NIR) spectrum, making them versatile for various applications.
• Low Cost: N-BK7 is a cost-effective alternative to other materials like UV Fused Silica or Calcium Fluoride, offering high performance at a lower price point.
• Great Resistance to Scratches and Abrasions: The material’s durability ensures long-lasting performance and reduced maintenance, even in demanding environments.
• Low Inclusion Content: The high purity of N-BK7 glass results in fewer inclusions, which translates to better optical quality and less scattering of light.
• Superior Surface Quality (40/20 Scratch/Dig): The surface quality specification of 40/20 ensures minimal surface imperfections, reducing scatter and enhancing image clarity.
• High Precision (λ/4-λ Irregularity): The lenses have a surface irregularity of λ/4 to λ, providing high accuracy in lens shape and reducing optical aberrations for improved focusing.
• Versatile Applications: N-BK7 plano-convex lenses are suitable for a variety of uses, including emitters, detectors, imaging instruments, lasers, and fiber optics.

Broadband AR Coatings (BBAR):

Standard N-BK7 plano-convex lenses can be uncoated or coated with BBAR coatings to accommodate multi-spectrum and tunable laser applications. Typical wavebands for BBAR coatings include:

• 350-650nm
• 400-700nm
• 650-1050nm
• 700-1100nm
• 1050-1580nm
• 1100-1650nm

Applications:

• Emitters and Detectors: Enhancing light collection and focusing.
• Imaging Instruments: Improving image quality and reducing aberrations.
• Lasers: Focusing and collimating laser beams.
• Fiber Optics: Efficient light coupling and transmission.

Kingwin Optics offers both stocked and custom N-BK7 Plano-convex lenses, with a diameter range of 0.5-300mm, allowing flexible integration into various optical systems such as emitters, detectors, imaging instruments, lasers, and fiber optics.