150mm BK7 negative meniscus lens

Product Description

Large 150mm BK7 Negative Meniscus Diverging Lens – Zemax-Verified Performance

This is a premium, large-aperture negative meniscus lens fabricated from high-quality BK7 optical glass. Featuring a classic diverging meniscus design with radii of curvature R₁ ~ -250mm (concave) and R₂ ~ -940mm (convex), this lens provides strong, controlled negative power with minimal spherical aberration. Its performance has been validated through optical modeling (Zemax simulation based on measured data), confirming its utility in precision optical systems.

Key Specifications (Zemax-Verified):

• Diameter: 150 mm (~6 inches)

• Center Thickness: ~9 mm

• Radii of Curvature:

  • Surface 1 (concave): ~ -250 mm

  • Surface 2 (convex): ~ -940 mm

• Material: BK7 crown glass (high clarity, excellent transmission from 350 nm to 2.0 µm)

• Focal Length: Approximately -659 mm (strongly diverging)

• Coating: Uncoated polished (maximizes broadband transmission)

• Condition: Excellent surplus – flawless optical surfaces, no scratches or digs

Why This Meniscus Lens Is Exceptional:

• Controlled Divergence: The meniscus shape minimizes spherical aberration compared to a simple plano-concave lens, providing smoother wavefronts.

• Large Aperture: 150mm clear aperture allows for handling large-diameter beams with minimal vignetting.

• Modeling Confidence: Zemax simulation based on measured parameters ensures predictable performance in optical designs.

Applications:

• Laser Beam Expansion: As the diverging element in a Galilean beam expander for CO₂, diode, or Nd:YAG lasers.

• Aberration Correction: Use as a field flattener or corrector in imaging systems, telescope eyepieces, or custom relay optics.

• Optical Experimentation: Ideal for lab setups requiring controlled negative power, wavefront manipulation, or educational demonstrations.

• Custom Optical Assemblies: Integrate into multi-lens systems for divergence control or pupil matching.

Orientation Note:

For optimal performance, orient the stronger concave surface (R₁ ~ -250mm) toward the collimated or converging input beam.