| Date | 1878 |
| Author | Powell |
| Contribution | With Lealand, improved on the achromatic condenser lenses that they had been making for some years. |
| Reference | Bradbury |
| Notes | They now introduced one with numerical aperture of 0.99. See 1850. They later produced apochromatic condenser lenses. |
| Category | Microscopy |
| Pathogen Class | General |
Copyright © 2007- William C. Campbell. All rights reserved.