This is description of this part:
Amici-Bertrand lens for the photo intermediate tube of Carl Zeiss Universal / Photomicroscope class microscopes.
In Zeiss Universal / Zeiss Photomicroscope class microscopes, the intermediate tube (https://www.microscopeparts.eu/part/99571) contains a horizontally mounted barrel with a prism that splits the light towards the trinocular/photo port. The individual positions are switched by pulling and pushing the control knob (https://www.microscopeparts.eu/part/91040). The Amici-Bertrand lens, used for aligning DIC and the phase contrast rings, is mounted in the same place - and that is the lens presented here.
Why is this lens located in the light-splitting module, even though the PH marking is on the turret of the Optovar magnification changer? The reason is simple: the first Zeiss Universal models had no magnification changer, so the Amici-Bertrand lens was mounted next to the beam splitting prism and is swung in with the same knob that switches the photo mode. When the magnification changer (with the 1.25x / 1.6x and 2x positions) was added to the newer models, a PH position was provided on the changer as well, containing no lens at all (an empty slot) - because the Bertrand lens for phase contrast stayed where it had always been. You can see the construction of the magnification changer and this empty slot here: https://www.microscopeparts.eu/part/91043.
This lens fits the intermediate tubes used in the following microscopes:
- Zeiss Universal
- Zeiss Photomicroscope I
- Zeiss Photomicroscope II
- Zeiss Photomicroscope III / III RS
- Zeiss Ultraphot
This is a service part for those who need to replace this element in their microscope, or who want to use the Amici-Bertrand lens for their own DIY projects.
Over the years, Carl Zeiss Photomicroscope series microscopes have acquired various names commonly used by their owners. These include, among others:
- Zeiss Photomikroskop
- PM, e.g. Zeiss PM II or Zeiss PM III
- Zeiss Phomi, e.g. Zeiss Phomi II
It should also be mentioned that Zeiss Photomicroscope microscopes were sold under the Opton brand as well.
What is this part needed for?
- if you have a microscope in which this element is missing (e.g. somebody unscrewed the lens for cleaning and never put it back)
- if you have a microscope in which this lens does work, but is in very poor condition, e.g. fungus damaged or scratched
- if you want to use this Amici-Bertrand lens for your own DIY project or another microscope
