N-BK7 Double-Concave Lens
- Double-concave lens has negative focal length.
- DCV lens diverges light to form virtual images.
- Suitable for image reduction within finite conjugates.
- N-BK7 lenses are general purpose and low cost lenses.
Application Notes
- DCV for Beam Diversion : DCV is used with collimated beam to diverge it on other side.
- DCV in an Optical System : DCV lens when placed in an optical system, increase the focal length of the system with additional benefits of offsetting Spherical Aberrations caused by other lenses within the system.
- DCV in Scanners : DCV is used for scanning in medical equipment and CD/DVD players, where laser beam is diverged to sharply access a specific area.
- DCV in Imaging : DCV is used when the object and image are at absolute conjugate ratios closer to 1:1 with a converging input beam.
Specification
- Material : N-BK7
- Focal length : ±1%.
- Diameter available : Ø5 to Ø100.
- Diameter Tolerance : +0/-0.1 mm.
- Clear aperture : 90%.
- Center Thickness : ±0.1mm.
- Centeration : Better than 3 arc min.
- Surface Irregularity : Lambda/4 @ 632.8 nm.
- Surface quality : 40-20 Scratch-Dig.
- Design Wavelength : 587.6 nm.
- Wavelength range : 350 nm- 2 µm. (Un-Coated)
- AR Coatings available : A)BBARC ; B) Laser V-Coating. Note : 1. To avoid reflection losses which result in ghost images, we suggest you to use AR-coating from our coating catalogue.
2. For good performance under low light conditions, we suggest you to use AR-coating from our coating catalogue.
3. Customized designs are available from diameters of 3 mm to 300 mm with your specifications and coating options.
Product Matrix
N-BK7 Double Concave Lens- Diameter 5 mm
| Quantity | Doc | Part Number | Diameter (mm) | Focal Length (mm) | Back Focal Length (mm) | Center Thickness (mm) | Edge Thickness (mm) | |
|---|---|---|---|---|---|---|---|---|
| DCV-5-10 | 5 | -10 | -10.2 | 0.8 | 1.4 | |||
| DCV-5-15 | 5 | -15 | -15.3 | 1 | 1.4 |
N-BK7 Double Concave Lens- Diameter 10 mm
| Quantity | Doc | Part Number | Diameter (mm) | Focal Length (mm) | Back Focal Length (mm) | Center Thickness (mm) | Edge Thickness (mm) | |
|---|---|---|---|---|---|---|---|---|
| DCV-10-15 | 10 | -15 | -15.4 | 1 | 2.6 | |||
| DCV-10-20 | 10 | -20 | -20.6 | 1.1 | 2.3 |
N-BK7 Double Concave Lens- Diameter 12.5 mm
| Quantity | Doc | Part Number | Diameter (mm) | Focal Length (mm) | Back Focal Length (mm) | Center Thickness (mm) | Edge Thickness (mm) | |
|---|---|---|---|---|---|---|---|---|
| DCV-12.5-20 | 12.5 | -20 | -20.5 | 1.2 | 3.1 | |||
| DCV-12.5-25 | 12.5 | -25 | -25.3 | 1.3 | 2.8 |
N-BK7 Double Concave Lens- Diameter 25 mm
| Quantity | Doc | Part Number | Diameter (mm) | Focal Length (mm) | Back Focal Length (mm) | Center Thickness (mm) | Edge Thickness (mm) | |
|---|---|---|---|---|---|---|---|---|
| DCV-25-30 | 25 | -30 | -30.6 | 1.5 | 6.7 | |||
| DCV-25-40 | 25 | -40 | -41 | 2 | 5.8 | |||
| DCV-25-50 | 25 | -50 | -50.7 | 2.5 | 5.5 |