Compare Model Drawings, CAD & Specs Diameter Effective Focal Length (EFL) F/# Surface Quality Availability Price
Focusing Lens, 25.4 mm, N-BK7/A, Bi-Convex, 33 mm FL, Uncoated
$908
In Stock
25.4 mm 33.0 mm 1.3 60-40 scratch-dig
In Stock
Focusing Lens, 38.1 mm, N-BK7/A, Bi-Convex, 50 mm EFL, Uncoated
$130
In Stock
38.1 mm 50.0 mm 1.3 60-40 scratch-dig
In Stock
Focusing Lens, 38.1 mm, N-BK7/A, Bi-Convex, 75 mm EFL, Uncoated
$121
In Stock
38.1 mm 75.0 mm 2 60-40 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 6.35 mm Diameter, 6.4 mm EFL, Uncoated
$41
In Stock
6.35 mm 6.4 mm 1 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 6.35 mm Diameter, 12.7 mm EFL, Uncoated
$35
In Stock
6.35 mm 12.7 mm 2 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 6.35 mm Diameter, 25.4 mm EFL, Uncoated
$35
In Stock
6.35 mm 25.4 mm 4 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 12.7 mm Diameter, 12.7 mm EFL, Uncoated
$35
In Stock
12.7 mm 12.7 mm 1 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 12.7 mm Diameter, 19.0 mm EFL, Uncoated
$35
In Stock
12.7 mm 19.0 mm 1.4 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 12.7 mm Diameter, 25.4 mm EFL, Uncoated
$35
In Stock
12.7 mm 25.4 mm 2 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 12.7 mm Diameter, 38.1 mm EFL, Uncoated
$35
In Stock
12.7 mm 38.1 mm 3 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 12.7 mm Diameter, 50.2 mm EFL, Uncoated
$35
In Stock
12.7 mm 50.2 mm 3.9 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 12.7 mm Diameter, 62.9 mm EFL, Uncoated
$35
In Stock
12.7 mm 62.9 mm 4.9 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 12.7 mm Diameter, 75.6 mm EFL, Uncoated
$35
In Stock
12.7 mm 75.6 mm 5.9 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 25.4 mm Diameter, 19.0 mm EFL, Uncoated
$41
In Stock
25.4 mm 19.0 mm 0.7 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 25.4 mm Diameter, 25.4 mm EFL, Uncoated
$41
In Stock
25.4 mm 25.4 mm 1 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 25.4 mm Diameter, 38.1 mm EFL, Uncoated
$41
In Stock
25.4 mm 38.1 mm 1.5 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 25.4 mm Diameter, 50.2 mm EFL, Uncoated
$41
In Stock
25.4 mm 50.2 mm 1.9 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 25.4 mm Diameter, 62.9 mm EFL, Uncoated
$41
In Stock
25.4 mm 62.9 mm 2.4 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 25.4 mm Diameter, 75.6 mm EFL, Uncoated
$41
In Stock
25.4 mm 75.6 mm 2.9 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 25.4 mm Diameter, 88.3 mm EFL, Uncoated
$41
In Stock
25.4 mm 88.3 mm 3.4 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 25.4 mm Diameter, 100 mm EFL, Uncoated
$41
In Stock
25.4 mm 100 mm 3.9 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 25.4 mm Diameter, 125 mm EFL, Uncoated
$41
In Stock
25.4 mm 125 mm 4.9 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 25.4 mm Diameter, 150 mm EFL, Uncoated
$41
In Stock
25.4 mm 150 mm 5.9 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 25.4 mm Diameter, 175 mm EFL, Uncoated
$41
In Stock
25.4 mm 175 mm 6.8 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 25.4 mm Diameter, 200 mm EFL, Uncoated
$41
In Stock
25.4 mm 200 mm 7.8 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 25.4 mm Diameter, 250 mm EFL, Uncoated
$41
In Stock
25.4 mm 250 mm 9.8 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 25.4 mm Diameter, 500 mm EFL, Uncoated
$41
In Stock
25.4 mm 500 mm 19.6 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 25.4 mm Diameter, 1000 mm EFL, Uncoated
$41
In Stock
25.4 mm 1000 mm 39.3 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 50.8 mm Diameter, 38.1 mm EFL, Uncoated
$69
In Stock
50.8 mm 38.1 mm 0.7 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 50.8 mm Diameter, 50.2 mm EFL, Uncoated
$69
In Stock
50.8 mm 50.2 mm 0.9 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 50.8 mm Diameter, 62.9 mm EFL, Uncoated
$69
In Stock
50.8 mm 62.9 mm 1.2 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 50.8 mm Diameter, 75.6 mm EFL, Uncoated
$69
In Stock
50.8 mm 75.6 mm 1.4 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 50.8 mm Diameter, 88.3 mm EFL, Uncoated
$69
In Stock
50.8 mm 88.3 mm 1.7 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 50.8 mm Diameter, 100 mm EFL, Uncoated
$69
In Stock
50.8 mm 100 mm 1.9 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 50.8 mm Diameter, 125 mm EFL, Uncoated
$69
In Stock
50.8 mm 125 mm 2.4 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 50.8 mm Diameter, 150 mm EFL, Uncoated
$69
In Stock
50.8 mm 150 mm 2.9 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 50.8 mm Diameter, 175 mm EFL, Uncoated
$69
In Stock
50.8 mm 175 mm 3.4 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 50.8 mm Diameter, 200 mm EFL, Uncoated
$69
In Stock
50.8 mm 200 mm 3.9 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 50.8 mm Diameter, 250 mm EFL, Uncoated
$69
In Stock
50.8 mm 250 mm 4.9 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 50.8 mm Diameter, 300 mm EFL, Uncoated
$69
In Stock
50.8 mm 300 mm 5.9 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 50.8 mm Diameter, 400 mm EFL, Uncoated
$69
In Stock
50.8 mm 400 mm 7.8 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 50.8 mm Diameter, 500 mm EFL, Uncoated
$69
In Stock
50.8 mm 500 mm 9.8 40-20 scratch-dig
In Stock
Bi-Convex Lens, N-BK7, 50.8 mm Diameter, 1000 mm EFL, Uncoated
$69
In Stock
50.8 mm 1000 mm 19.6 40-20 scratch-dig
In Stock

Specifications

  • Lens Shape
    Bi-Convex (Double Convex)
  • Lens Material
    N-BK7
  • Antireflection Coating
    Uncoated
  • Surface Accuracy, Irregularity
    λ/4
  • Surface Accuracy, Power
    1.5 λ
  • Surface Flatness
    λ/4
  • Centration
    ≤3 arc min
  • Chamfers
    0–0.8 mm face width
  • Chamfers Angle/Tolerance
    45° ±15°, typical
  • Focal Length Tolerance
    ±1 %
  • Diameter Tolerance
    +0/-0.1 mm
  • Center Thickness Tolerance
    ±0.1 mm
  • Clear Aperture
    ≥central 90% of diameter
  • Cleaning

Features

N-BK7 Substrates for VIS and NIR Applications

N-BK7 is an excellent lens material for most visible and near infrared applications. It is the most common borosilicate crown optical glass, and it provides great performance at a good value. Its high homogeneity, low bubble and inclusion content, and straightforward manufacturability make it a good choice for transmissive optics. N-BK7 is also relatively hard and shows good scratch resistance. The transmission range for BK 7 is 380 to 2100 nm. It is not recommended for temperature sensitive applications, such as precision mirrors. For more information, refer to our optical materials technical note.

Standardized Bi-Convex Focal Lengths

Standard effective focal lengths on our double-convex lenses provide a systematic approach allowing for lenses of different sizes and materials to be interchanged without requiring other changes to your optical system.

Bi-Convex Lens Shape for Focusing

Bi-Convex lenses are the best choice when the object and image are at equal or near equal distance from the lens. When the object and image distance are equal (1:1 magnification), not only is spherical aberration minimized, but also coma, distortion, and chromatic aberration are identically canceled due to the symmetry. Bi-convex lenses function similarly to plano-convex lenses in that they have a positive focal length, and focus parallel rays of light to a point. Both surface are spherical and have the same radius of curvature, thereby minimizing spherical aberration. As a guideline, bi-convex lenses perform within minimum aberration at conjugate ratios between 5:1 and 1:5. Outside this magnification range, plano-convex lenses are usually more suitable.

Mounting Options

We offer a full range of optical lens mounts to meet various experimental requirements. Below lists the recommended mounts for spherical lenses of standard sizes. Please see our Lens Mount Guide for additional information.

Lens Diameter LH-A-GRP
A-Line™ Lens Mounts
LT_Series_group_update
LT Series Lens Tubes
OM-multi_axis_lens_pos-S
LP Series Lens Positioners
optics-cage-plus-S
Optics Cage Plus Series
76.2 mm (M-) LH-3A N/A N/A N/A
50.8 mm (M-) LH-2A
LH-2N
LT20-05
LT20-10
LT20-20
LT20-30
LP-2A
LP-2A-XY
LP-2A-XYZ
N/A
38.1 mm (M-) LH-1.5A LT20 lens tube with
LH-2R1.5 adapter
LP-2 lens positioner with
LPLH-1.5T adapter
N/A
25.4 mm (M-) LH-1A
LH-1N
LH-1XY
LH-1TZ-A
LH-1TZ
LT10-05
LT10-10
LT10-20
LT10-30
LP-1A
LP-1A-XY
LP-1A-XYZ
OC1-LH1-S
OC1-LH1
OC1-LH1-TZ
OC1-LH1-XY
OC1-LH1-XYA
OC1-LH1-XYC
OC1-LH1-XYZ
12.7 mm (M-) LH-0.5A
LH-05N
LT05-05
LT05-10
LP-05A
LP-05A-XY
LP-05A-XYZ
N/A
6.35 mm LH-05DB with
LH-50R25 adapter
LT05 lens tube with
LH-50R25 adapter
LP-05 lens positioner with
LPLH-25T adapter
N/A

For non-standard sizes not listed above, check out our variable size lens mounts.