These lenses may be used to increase the numerical aperture of a positive lens assembly, without an undue increase in the aberrations.
| Specifications | |
| Material | Optical glass, Crystal, Sapphire |
| Dimension Tolerance | +/-0.05mm |
| Centration | 3 arc minutes |
| Clear Aperture | >95% |
| Surface Figure | 1/4 wave @632.8nm |
| Surface Quality | 10-5 scratch and dig |
| Bevel | 0.1mmX45 degree |
| Coating | None, AR, AL... |
| Dia.(mm) | F(mm) | R1(mm) | R2(mm) | Tc(mm) | Te(mm) | Item Number |
| 25.4 | 100.00 | 33.72 | 90.00 | 4.0 | 2.5 | EMP-001 |
| 25.4 | 150.00 | 42.52 | 90.00 | 4.0 | 3.0 | EMP-002 |
| 25.4 | 200.00 | 49.03 | 90.00 | 3.5 | 2.8 | EMP-003 |
| 25.4 | 300.00 | 94.08 | 235.00 | 3.5 | 3.0 | EMP-004 |
| 25.4 | 350.00 | 102.90 | 235.00 | 3.5 | 3.1 | EMP-005 |
| 25.4 | 400.00 | 110.72 | 235.00 | 3.5 | 3.1 | EMP-006 |
| 25.4 | 500.00 | 123.90 | 235.00 | 3.5 | 3.2 | EMP-007 |
| 25.4 | 600.00 | 204.95 | 600.00 | 3.5 | 3.2 | EMP-008 |
| 25.4 | 1000.00 | 278.34 | 600.00 | 3.5 | 3.3 | EMP-009 |
| 25.4 | 2000.00 | 380.54 | 600.00 | 3.5 | 3.4 | EMP-010 |
| 25.4 | 4000.00 | 466.12 | 600.00 | 3.5 | 3.5 | EMP-011 |
