Silicon (Si) plano-concave lenses are high-performance negative optical elements manufactured from optical-grade monocrystalline silicon. Featuring one flat surface and one spherical concave surface, these lenses provide a negative focal length ideal for beam expansion, divergence control, and optical system miniaturization in the infrared spectrum, boasting high refractive index and excellent thermal conductivity.

Technical Applications & Industrial Use Cases Due to their high refractive index, robust mechanical durability, and exceptional transmission in the near-to-mid infrared bands, silicon plano-concave lenses are widely deployed across high-tech industries:
  • Infrared Laser Systems: Act as divergence and beam expansion optics in high-powered infrared laser setups operating around 3 to 5 micrometers.
  • Thermal Imaging & FLIR: Utilized in thermal cameras, night vision equipment, and infrared sensing assemblies requiring rugged optical windows and lenses.
  • Spectroscopy & Defense Optics: Deployed in multi-spectral optical instruments, pyrometers, and aerospace guidance systems.
Key Specifications & Performance Advantages
  • Material: Optical-Grade Monocrystalline Silicon (Si) optimized for infrared applications.
  • Design Wavelength: Calibrated for precision performance at 4 micrometers with strict focal length tolerance.
  • Surface Quality: High-precision 60-40 scratch-dig with tight centration tolerance (< 3 arcmin) and protective chamfers.
  • Coating Options: Available uncoated or featuring specialized low-absorption infrared anti-reflective (IR1) coatings (average reflectance < 1.5% across 3 to 5 micrometers) to maximize throughput.
Download Datasheet of Silicon Plano Convex Lens