38 PART II A Deeper Look into a Light Microscope
Example Term Description
ZEISS Producer of the objective
Plan-
APOCHROMAT
This line indicates the class of the objective, whether it is color
corrected and flat-field corrected. An »LD« before the name is
a sign for an objective with a long working distance, normally
corresponding to a slightly lower resolution. »Epi« means
objectives for reflected light illumination.
63×/1,4 Oil This objective comes with a magnification of 63×. The numerical
aperture is 1.4. »Oil« tells you that this is an objective to be used
with the matching oil as immersion fluid.
Korr The objective comes with adjustable cover glass correction.
∞/ 0,19–0,15 Lens image distance is infinite. The cover-glass thickness can be
adapted between 0.19 and 0.15.
DIC, Ph This objective is built for use with a certain contrasting technique.
Correction collar Already the Korr tells you that you can use the objective with
cover glasses of varying thickness. With the correction collar, you
adjust the lens position to the cover glass thickness and also the
immersion fluid.
Color coding The color code tells you at one glance which magnification the
objective provides:
✔✔ black: 1×/1.25×
✔✔ brown: 2.5×
✔✔ red: 4×/5×
✔✔ orange: 6.3×
✔✔ yellow: 10×
✔✔ green: 20×
✔✔ light blue: 40×
✔✔ dark blue: 63×
✔✔ white: 100×
Table 5.1: Markings on an objective
/microscopy
