Negative
Achromatic Lenses |
| |
| Consisting of two optical elements cemented together,
negative achromats are corrected for color and on-axis aberrations.
Used predominantly as Barlow lenses to extend focal lengths, they
are often combined with positive achromatic mirror systems and CCD
lenses. All dimensions are in mm. |
|
Specifications: |
Diameter |
Surface
Quality |
Dia.
Tolerance |
C.T.
Tolerance |
Centering
Tolerance |
Bevel
(see Notes) |
6.25 - 25.00 |
40-20 |
0 |
0.2 |
3 arc min. |
0.25 x 45 |
Notes |
Annulus |
Negative outer
surface has an annulus of 0.3 max |
Clear
Aperture |
3
- 10 diameter: |
CA >=
90% diameter |
10.1
- 50 diameter: |
CA
= (diameter) - 1.0mm |
Coating |
1/4wave
MgF2 @ 550nm |
EFL
Tolerance |
2% |
E.T.
Tolerance |
Reference |
Design
Wavelength |
587.6nm |
|
Plano-Convex Lenses
