Round\Plano Concave K9/ Bk7 Optical Glass Lenses
Product Despriction
The plano concave lens is used to diverge the parallel light outward. The focal length of the flat concave lens is negative and the spherical
aberration is also negative. It can be used to correct the phase difference, spherical aberration, coma and distortion of other lenses. Similar to the flat
concave mirror, the side is generally opposite to the far object surface or infinity.
K9 plano concave spherical lens can see the transmittance of near infrared (350-2000nm).
H-K9L (N-BK7) is an optical glass commonly used in the preparation of optical elements.
These uncoated plano concave lenses are prepared using H-K9L (N-BK7) conforming to ROHS standard. The collimated beam can converge on
the rear focus, or the point light source can be changed into a collimated beam.
Technical Parameters
| Items |
Parameters |
| Material |
optical glass, H-K9L (N-BK7) |
| Outer circle: |
3mm-500mm ± 0.1mm |
| Radius of curvature: |
± 1mm - ± 50000mm ± 1% |
| Center thickness tolerance: |
± 0.05mm (we can process to ± 0.01mm with high precision) |
| Center deviation: |
3′(we can process to 30 ″with high precision) |
| Surface accuracy: |
λ/ 8 (high precision, we can process to 1 / 10λ) |
| Surface quality: |
60/40 (we can process to 10-5 with high precision) |
| Effective caliber: |
≥90% |
| Coating: |
Maultilayer Antireflective Coating
A:400-700nm
B:650-1050nm
C:1000-1650nm |
Certificate
Factory

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