This is description of this part:
Aplanatic bright-field microscope condenser Apl. 1,4 by Carl Zeiss Jena, with mounting, wide-field lens and iris diaphragm.
Basic data and parameters:
Manufacturer: Carl Zeiss Jena
Designation: Apl. 1,4
Name of the mount according to the manufacturer's catalogue: Kondensoreinhänger mfl 2, Bestellnummer 301080:021.26/0
Name of the condenser according to the manufacturer's catalogue: Aplanatischer Kondensor 1.4 mo / ms (applies only to the upper optical part)
Name of the condenser according to the manufacturer's catalogue: Kondensor hoher Lichtstärke mit Vorschaltsystem (applies to the entire module)
Version: grey colour with a black upper lens. Variant without the "dot" in the name after "Apl"
Numerical aperture N.A.: 1.4
Aperture diaphragm: yes, attached to the condenser mount
Wide-field lens: yes, it can be swung out of the optical path. This is the version with the large lens in a housing (see description below)
Removable upper lens: yes, it can be rotated
Mounting diameter: the optical part (condenser without diaphragm) has a mounting diameter of 39.5 mm and can be unscrewed from the condenser mount
Operating modes: the condenser can be used both as a dry condenser and as an immersion condenser
The entire part consists of the following elements:
- upper Apl 1,4 lens
- screw-on/removable condenser (mo / ms)
- iris diaphragm screwed onto the condenser mount
- condenser mount model mfl 2
- swing-out wide-field lens
- two centering screws
This condenser is mainly used in Carl Zeiss Jena Fluoval / Fluoval-2 fluorescence microscopes. It is optimal for use with high-numerical-aperture apochromatic microscope objectives. For precisely this reason, users often install it on Carl Zeiss Jena Ergaval and Carl Zeiss Jena Amplival microscopes equipped with apochromatic objectives (Carl Zeiss Jena Apochromat).
It is worth mentioning again that this condenser can be used in two modes:
- without immersion oil on the upper lens of the condenser. In this case, it operates as a "dry condenser" and its numerical aperture N.A. is 0.9.
- with immersion oil on the upper lens of the condenser (i.e. underneath the microscope slide). In this case, it operates as an "immersion condenser" and its numerical aperture N.A. is 1.4, allowing a very bright image to be obtained – this is important in fluorescence microscopy or when using high-N.A. immersion objectives.
During production, this condenser was available in several versions:
- with a black upper lens, a dot in the model name (Apl. 1,4) and a wide-field module consisting of a single lens
- with a black upper lens, without a dot in the model name (Apl 1,4) and a single wide-field module consisting of several lenses (including one with a very small diameter)
- with a grey upper lens marked Apl 1,4mo2 and a single wide-field module consisting of several lenses (including one with a very small diameter)
- with a grey upper lens marked Apl 1,4mo2 and a wide-field module consisting of two independently swing-out lenses, each on its own mount
I have not found any information anywhere as to whether the above-mentioned versions differ in their operation. From experience, I know that they are used interchangeably – but I do not know whether any differences in operation can actually be noticed.
Mechanically, this condenser is mounted on dovetail rails located underneath the microscope stage. In Carl Zeiss Jena Ergaval microscopes, this is a separate condenser mounting block, whereas in Carl Zeiss Jena Fluoval / Amplival microscopes, the dovetail is located on the microscope stage holder block.
The manufacturer describes this condenser as follows: "High-intensity condenser with an auxiliary system for illuminating large fields while imaging the field diaphragm. [...] The condenser of the FLUOVAL 2 can be used as a dry and immersion condenser of the highest aperture to achieve the highest possible excitation intensity. It is equipped with a switchable wide-field system that illuminates the large fields of low-power objectives while providing a sharp image of the field diaphragm in the object plane."
What is this part needed for?
- if you own a used microscope without a condenser
- if your microscope is equipped with a standard Abbé condenser with a numerical aperture of N.A. 1.2
- if you already have a condenser but it is damaged or of poor optical quality
- if you want to modify this condenser holder to install a dark-field condenser
- if you need components from this condenser for your own DIY projects
