Biconcave Lens 20mm Diameter −39.7mm Focal Length 400 - 700nm

SLB-20B-40NM

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.

Details

◦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.

Weitere Informationen

Weitere Informationen
Name	Biconcave Lens 20mm Diameter −39.7mm Focal Length 400 - 700nm
Gewicht	0.0500kgs
Standardbeschichtungen verfügbar	Nein
Leitfaden	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.
Anmerkung	-
Achtung	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.
Durchmesser φD	20mm
Brennweite	−39.7mm
Material	BK7
Design Wavelength	546.1nm
Refractive index n<sub>e</sub>	1.519
Coating	Broadband Multilayer antireflection coating (400 - 700nm)
Transmmittance	> Average 99%
Laser Damage Threshold	4J/cm² (Laser pulse width ; 10ns , Repetition frequency ; 20Hz)
Clear aperture	85% of the diameter
Surface Quality (Scratch-Dig)	20-10
Wavelength range of Antireflection Coating	400 - 700nm
Diameter φD	φ20mm
Focal length f	−39.7mm
Edge thickness te	4.4mm
Center thickness tc	2mm
Back focal length fb	−40.3mm
Radius of curvature r	41.52mm
Centration	＜1′

Auf Lager

SKU

SLB-20B-40NM

63,60 €

Biconcave Lens 20mm Diameter −39.7mm Focal Length 400 - 700nm

Resources & Downloads