Drum lenses are glass spheres, ground down axially to provide a mounting surface. The ground circumference D simplifies handling issues typically associated with ball lenses. Ideal for optical transmission in fiber communications. Type B Drum lenses have a polished plano-surface for direct fiber contact and perform as elongated PCX lenses.
Drum lenses are easier to mount and handle than standard ball lenses.
| SPECIFICATIONS | |
| material | N-BK7 or equivalent |
| DIAMETER TOLERANCE | +0.0, -0.2mm |
| radius | +0.0, -0.0015mm |
| length | +0.03mm, -0.03mm |
| CENTRATION | 3 arc minutes |
| CLEAR APERTURE | >80% |
| SURFACE FIGURE: IRREGULARITY(N) | <0.25 fringe |
| SURFACE QUALITY | 40/20 scratch and dig |
| BEVEL | < 0.3 mm x 45° |
| COATING | With AR coating on outside surfaces |
