Biconcave Lens 50.8mm Diameter −249.5mm Focal Length Uncoated

SLB-50.8B-250N

These biconcave lenses are used when a very high negative power is required. They can be used in a multi-element system or alone to produce a diverging cone or virtual image. Sharpe edges, which are common in negative lenses, are removed by beveling to reduce the likelihood of chipping.
◦There are two types of biconvex lenses available; BK7 for use in visible range to infrared wavelength range.
◦Our lenses are listed by outside diameter and focal length to assist your selection according to required specifications.
More Information
Name Biconcave Lens 50.8mm Diameter −249.5mm Focal Length Uncoated
Weight 0.0500kgs
Standard Coatings Available Yes
Guide
  • Lenses are available in a large selection and in custom sizes and focal lengths.
  • In addition to our standard coating we offer custom anti-reflective coating at specific wavelengths.
Remark -
Attention
  • When a concave lens is used in combination with a convex lens it will be able to converge the light and can projected a suitable image.
  • The biconvex spherical lens has chromatic aberration, and the focal length will vary depending on the wavelength. Please check the “wavelength characteristic of the focal length data” on “Technical Data” for the focal lengths of each wavelength.
  • Transmissions losses due to reflection off the front and rear surfaces of the lens can be minimized by coating the surfaces. Consult our Sales Team for anti-reflection coatings suitable for your application.
  • The outer edge of the concave side is chamfered and the result is possibility that the lens may have a smaller edge thickness for this design.
Diameter φD 50.8mm
Focal length −249.5mm
Material BK7
Design Wavelength 546.1nm
Refractive index n<sub>e</sub> 1.519
Coating Uncoated
Clear aperture 90% of the diameter
Surface Quality (Scratch-Dig) 20-10
Wavelength range of Antireflection Coating Uncoated
Diameter φD φ50.8mm
Focal length f −249.5mm
Edge thickness te 5.5mm
Center thickness tc 3mm
Back focal length fb −250.5mm
Radius of curvature r 259.5mm
Centration <1′
In stock
SKU
SLB-50.8B-250N
$82.00

Delivery in : in stock

These biconcave lenses are used when a very high negative power is required. They can be used in a multi-element system or alone to produce a diverging cone or virtual image. Sharpe edges, which are common in negative lenses, are removed by beveling to reduce the likelihood of chipping.

Resources & Downloads