These lenses have negative focal lengths. These lenses diverge collimated incident light and form virtual images, which are seen through the lens. They are often used to expand light or increase focal..
| Material: | BK7 |
| Design Wavelength: | 546.1nm, n=1.518721 |
| Diameter Tolerance: | +0.0/-0.1mm |
| Paraxial Focal Length: | ±2% |
| Centration: | 3 arc minutes |
| Surface Figure : | l/4 @ 632.8 nm |
| Surface Quality: | 60/40 |
| Clear Aperture: | >80% |
| Bevel: | <0.25mm X 45° |
| Coating: | Uncoated |