Objective, Total Magnification And Useful Magnification - Olympus SC30 User Manual

Adjusting the Lamp You can generally skip adjusting the lamp with modern microscopes, provided
Objective, Total Magnification and
Useful Magnification
Terminology The two most important parameters of an objective (magnification and numerical
Magnification An objective's engraved magnification is considerably important for the total
Numerical Aperture The numerical aperture is the characteristic of an objective which determines its
Total magnification The system's total magnification, to which an installed TV adaptor contributes, is
3)
Focus the image in the field diaphragm by using the condenser's height
adjustment.
Adjusting the condenser
Now the illuminated area is optimally set.
1)
Open the field diaphragm so that its edge is still completely within the visible
area.
2)
Center the image of the field diaphragm using the condenser's adjustment
screws.
A precisely adjusted condenser guarantees that only the area of the
specimen to be viewed is illuminated.
3)
Open the field diaphragm, until the edge of the field diaphragm is no longer
visible in the visual field.
that the lamp is located in a frame and the bulb is in a centered socket. When
you adjust the lamp, please turn to the corresponding manufacturer's
instructions for advice.
There are no general rules for which objective you select; one should always
keep the specimen and reason for observation in mind.
aperture) are engraved in the objective. First the magnification and then the
numerical aperture which is separated by a diagonal slash. Hence, the code 40
/ 0.65 marks an objective with a magnification of 40x and the numerical aperture
of 0.65.
magnification. However, one should note that the range of useful magnification
should not be surpassed.
capacity. The numerical aperture can also be found engraved on the objective.
It is based on the refraction index of the lenses being used as well as the
objective's angular aperture. The manufacturers are narrowly limited when
dealing with the refraction index, whereas the objective's angular aperture can
be increased by using appropriate measures. To achieve this, a fluid with a high
refraction index is placed between the cover slip and the objective. The
immersion objectives that can be used for this procedure are labeled
accordingly, they should only be used with the appropriate immersion fluid.
based on the actual size of the final image. This can be the image on the monitor,
as well as the image printed on paper. To determine the total magnification, it is
best to use a stage micrometer which can be shown on the monitor or the
printout. You can determine the total magnification by dividing the length of the
object shown by the set length on the micrometer.
Appendix I: Microscope settings