Europe, UK, Asia & RoW: [email protected] +44 (0)1622 859444 | USA & Canada: [email protected] +1 401-583-7846

My Cart

Biconvex Lens BK7 25mmdia x 50mm F.L. Uncoated

SKU: LBV5025
More Information
Focal Length (mm) 50.0
Diameter (mm) 25.0
Material BK7 or equivalent
Coating Uncoated

Biconvex lenses are one of the most simple lenses, but good quality, glass lenses with both faces convex and spherical.  Biconvex lenses are widely used for moderate quality imaging and also for focussing and control of laser beams. Generally biconvex lenses have both surfaces with the same curvature.

Knight Optical's stock range of quality grade N-BK7 or equivalent biconvex lenses are available uncoated or broadband AR coated for visible through to NIR applications. Knight optical also offers custom biconvex lenses to meet your requirements or alternatively edge stock lenses for a quick turnaround. We can supply alternative coatings where requested, including broadband 630-1100nm and 1050-1700nm anti reflective coatings for IR and telecoms applications.

Centring Accuracy:
Focal Length (@ 587nm):

Centre Thickness:
Edge Thickness:
Surface Quality:

N-BK7 or equivalent
+0.0 /-0.10mm
5 arcmin
± 0.2mm (< 10mm)
± 2.0% (10mm - 1000mm)
± 5.0% (> 1000mm)
± 0.2mm
± 0.2mm
<40-20 scratch/dig
Planoconvex lenses with suffix "AV2" are coated on both faces with:
Extended broadband multilayer antireflective coating <0.5%@450-900nm (AV2 specification)

Stock lenses can be edged to smaller diameters.
Stock lenses can be ground to rectangular and square shaped apertures.
Shorter focal lengths in relation to the diameter available.
Mounting into lens cells.
Special anti-reflective coatings for broadband applications and wavelengths
Broadband Multilayer AR, R.avg<0.4%@1050-1700nm
Broadband Multilayer AR, R.avg<0.4%@630-1100nm