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Bi-Concave Lenses ZNSE-BCC-001

ZnSe Bi-Concave Lenses

ZnSe Bi-Concave Lenses for IR beam expansion, with CVD ZnSe material, custom size review, and coating options.

Quick Specifications

Material CVD Zinc Selenide (ZnSe)
Diameter Range Ø1–Ø500 mm
Focal Length Range 4.5–1000 mm (negative)
Wavelength Range 0.6–16 µm (uncoated); 7–12 µm (IR2 AR coated)
Clear Aperture >90%
Diameter Tolerance +0.00/-0.1 mm
Thickness Tolerance ±0.1 mm
Surface Irregularity λ/4 @ 633 nm (λ/8 optional)
Centering Error 3 arcmin
Focal Length Tolerance ±2%
Chamfer 0.2 mm × 45°
Coating Options Uncoated or IR2 broadband AR (Ravg <1.5% @ 8–12 µm)

Product Description

Overview

ZnSe Bi-Concave Lenses have a negative focal length and can diverge a parallel beam to the virtual focus, making them an excellent choice for diverging convergent beams and for relay imaging systems. These lenses are based on CVD Zinc Selenide, which offers low absorption, thermal shock resistance, and wide transmission band (0.6–16 µm).

ZnSe is often used in optical systems that combine CO₂ lasers (operating at 10.6 µm) with helium-neon lasers for alignment, due to its low absorption in the red part of the visible spectrum.

Why This Material Matters

CVD Zinc Selenide (ZnSe) is selected for its low absorption and high infrared transmission, making it ideal for CO₂ laser optics and thermal imaging systems. The double-concave geometry provides negative focal length for beam expansion and divergence control.

Key Specifications

ParameterValue
MaterialCVD Zinc Selenide (ZnSe)
Diameter RangeØ1–Ø500 mm
Focal Length Range4.5–1000 mm (negative)
Wavelength Range0.6–16 µm (uncoated); 7–12 µm (IR2 AR coated)
Clear Aperture>90%
Diameter Tolerance+0.00/-0.1 mm
Thickness Tolerance±0.1 mm
Surface Irregularityλ/4 @ 633 nm (λ/8 optional)
Centering Error3 arcmin
Focal Length Tolerance±2%
Chamfer0.2 mm × 45°

Coating Options

Uncoated versions transmit from 0.6–16 µm. IR2 broadband anti-reflection coating is available with Ravg < 1.5% @ 8–12 µm for improved transmission in thermal imaging and CO₂ laser applications.

Typical Applications

  • IR beam expansion and divergence control
  • CO₂ laser beam delivery systems
  • Thermal imaging optics
  • Infrared relay imaging systems
  • Optical test benches and alignment systems
  • HeNe laser alignment in CO₂ laser systems

Safety Note

Zinc Selenide is a toxic material. Always wear gloves when handling ZnSe components and thoroughly clean hands after operation. Dispose of waste according to local regulations.

Engineering Notes

For custom production, specify focal length, diameter, center thickness, coating target, and beam diameter. Engineers should confirm wavelength, beam diameter, clear aperture, coating requirements, and mechanical envelope before final drawings are released.

Use the contact form or email [email protected] to request engineering review, coating options, or a quotation.

Key Features

CVD ZnSe material with low absorption and high IR transmission
Negative focal length for beam expansion and divergence control
Wide transmission range: 0.6–16 &micro;m (uncoated)
Thermal shock resistance for high-power laser applications
Compatible with CO₂ laser and HeNe alignment laser systems
IR2 broadband AR coating available for improved transmission
Custom diameter and focal length options available

Applications

IR beam expansion and divergence controlCO₂ laser beam delivery systemsThermal imaging opticsInfrared relay imaging systemsOptical test benches and alignment systemsHeNe laser alignment in CO₂ laser systems