- Deep dive
Liquid lens integration in microscopes
Non-telecentric configuration
The most straight-forward integration of a liquid lens in a microscopy system is to place it right above the objective lens, which is especially practical for infinity corrected objective lenses. The advantage of this configuration is that very large Z-ranges are achievable. For example, at a magnification of 40x a liquid lens with 5 diopters of tuning range will result in a working distance range of about 160µm. There is a magnification change across the Z-range, which is linear and reproducible.
| Z-range with 5D lens | Mag change | |
|---|---|---|
| 10x | 2560 µm | 0.3% / 100 μm |
| 20x | 640 µm | 1.9% / 100 μm |
| 40x | 160 µm | 14.8% / 100 μm |
Telecentric configuration without magnification change
Microscopy systems where magnification change is undesirable require a configuration where the liquid lens does not affect the magnification. This is possible by placing it inside a system of relay lenses at a conjugate pupil position. The achievable Z-range is generally smaller as in the non-telecentric configuration.
| Z-range with 5D lens | Mag change | |
|---|---|---|
| 10x | 1000 µm | 0% |
| 20x | 250 µm | 0% |
| 40x | 60 µm | 0% |