DF Biological Microscope
The DF Biological Microscope—launched in 1957—was the successor to the Homare UCE, which was the most advanced Olympus model in its time. The DF had a number of features that made it stand out from conventional microscopes:
First microscope to feature an external light source
Olympus changed from using a mirror to illuminate the specimen to the attachment of a light source. This development ensured sufficient light for high-magnification observations.
Mechanical stage capable of up-down movement
With the conventional method of focusing by moving the microscope head up and down, it was not possible to attach heavy items such as cameras to the microscope head. To solve this, Olympus developed a method to move the stage up and down in order to focus the image. This also meant that the user did not need to adjust their eye position.
Inclined microscope head
By inclining the microscope head, users were able to make observations in a more natural position. They could also use a combination of monocular and binocular viewing.
Trinocular lens barrels were then produced to allow the use of a binocular head with a phototube. A camera was attached to this tube, the specimen observed through the binocular head, and the image framed in the photography equipment. The image was then focused in the focus mirror on the phototube side and recorded.
Three microscope head options were therefore available according to the application or objective: monocular, binocular, or trinocular.