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• email: [email protected]
Zoom 6000 High Mag Zoom Lenses
Differential Interference Contrast (DIC) Modules
Prism In
Two Differential Interference Contrast (DIC) modules are
available from Navitar:
• the DIC Assembly Nikon-High Resolution module
(1-63726) and
• the original DIC Assembly module (1-63102).
Both modules can be used on any ultra coax version
(zoom or non-zoom) of the Zoom 6000.
DIC, when used with reflected light, can often be
interpreted as a true three-dimensional representation
of the surface geometry. It provides a clear distinction
between raised and lowered regions in the specimen
being viewed.
Using the DIC module in reflected light situations
Two polarizers, one in the illumination axis and one
in the viewing axis, are crossed at 90 degrees such that
when looking at a perfectly mirrored surface all light is
extinguished by the second polarizer.
A prism, made from two pieces of quartz, is then placed
between the illuminator beamsplitter and the objective.
Due to the optical properties of the quartz, the polarized
beam is split into two. The two beams, separated by a
Accessories
continued
minuscule amount, are polarized at 90 degrees to each
other and one beam is shifted in relation to the other -
a phase shift.
If the subject being viewed exhibits properties that
change the length of the optical path of either beam
(such as surface profiles, optical densities, etc.), both
beams will experience further phase shifts.
With transverse movement of the prism the phase shift-
ing performance of the prism may be accentuated and
the final image is modified. By adding a polarization
modifier, such as a 1/4 wave plate, after the illumination
polarizer, the final effects are modified further.
The DIC module works with object side NAs ranging
from 0.05 to 0.50, with optimum performance in the
range from 0.15 to 0.4. Lens attachments, operating in
the above range will serve for macro applications. Any
infinity corrected objectives designed for incident light
will suffice for micro applications. Operating param-
eters, such as magnification and FOV, will be the same
as Navitar’s existing tables for the Zoom 6000 system
being used.
Prism In
Prism Out
Prism In
Prism Out
3D topography of a flat panel display circuit highlighted
by employing differential interference contrast (DIC)
and the Zoom 6000.
