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FOCAL LENGTH - parallel rays of light after refraction through a lens
will converge to a focus at the focal point. The distance from the
optical center of the lens to the focal point is the focal length.
NUMERICAL APERTURE (NA) – a measure of an objective’s light
gathering capabilities. The concept may be compared to the F-valve in
photographic lenses. Generally speaking, objectives with N.A. values of
less than 1.00 are "Dry" objectives. Values of 1.00 or greater require oil
as a medium. Please note that condensers are part of the optical system
and are also assigned an N.A. value. That value must be at least as high
as that of the highest objective used.
PARFOCAL - a term applied to objectives and eyepieces when
practically no change in focus has to be made when an objective of one
power is substituted for another. The DIN objectives on your Swift
M3600 Series Microscope are parfocaled at the factory to a standard
45mm distance, so that only a slight turn of the fine adjustment is
required when a change is made from a lower to higher power.
RESOLVING POWER - the ability of a lens to clearly separate fine detail.
Resolving power is directly proportional to the numerical aperture of
the optical system.
WORKING DISTANCE – the distance from the lens of the objective to the
cover slip on the slide, when the specimen is in focus.
CORDLESS OPERATION (Cordless models)
The rechargeable battery should be fully charged for approximately 8
hours before the initial use. It can be charged by using the 4.5 volt A/C
adapter included with the microscope. The battery can be used to
power the illumination system for approximately 40 hours. If the
microscope is used in the same location, the A/C adapter can remain
plugged-in without damage to the battery or recharging system.
A battery power indicator meter is located in the front of the base.
Each blue LED light indicates the level of remaining battery power.
When the battery is fully charged, all 5 LED lights will be illuminated.
The
battery will need to be recharged when there is only 1 illuminated
LED remaining on the meter.
