OPERATION
Axio Scope.A1 Illumination and Contrasting Method Carl Zeiss
M60-2-0007 e 05/08 91
4.1.11 Adjusting Reflected Light Polarization – Proof of Bireflexion and Reflexion
pleochroism
(1) Application
The reflected light polarization is a contrasting method suited for cut surfaces of mineral ore, coal,
ceramics, special metals and alloys. Depending on the orientation of the crystals and the object details,
the cut surfaces often react differently when reflected in linearly polarized light.
The illumination light is polarized by the polarizer before passing through the objective onto the
specimen surface where it is reflected. Now the beam parts experience phase differences depending on
the structure and polarization optical rotations which, when passing through the analyzer, are
represented by different shades of grey. With the aid of a compensator with λ-plate the grey contrast can
be converted into a color contrast. Attention! Do not use a compensator 6x20 for this conversion!
A rotatable λ/4 plate in front of the objective (antiflex cap) helps eliminate, even when examining "dark"
specimen surfaces, the reflexes which are inevitable when working with objectives with very low scale
figures.
(2) Instrumentation
− Axio Scope.A1 with mounted and adjusted halogen lamp HAL 100
− Rotary stage Pol
− Objectives Epiplan-Neofluar Pol, EC Epiplan-Neofluar Pol, Epiplan Pol
− Reflector module DIC P&C or DIC Rot I P&C in the reflector turret/slider
or reflector module Pol P&C plus analyzer slider
or analyzer slider plus polarizer slider
(3) Adjusting reflected light polarization
• Adjust the microscope for reflected light/bright-field as described in chapter 685H685H4.1.7.
• If using the objective position with DIC position, remove the DIC slider, if necessary.
• Swing into the beam path the reflector module DIC P&C (
686H686HFig. 4-15/4) on the reflector turret, swing in
the reflector module Pol P&C and slide the analyzer slider into the compartment; or slide the analyzer
slider (
687H687HFig. 4-15/1) and the polarizer slider (688H688HFig. 4-15/2) into their compartments, if applicable. When
using the fixed sliders, the polarizer must be orientated in EAST-WEST direction and the analyzer in
NORTH-SOUTH direction.
• Put down the sample, adjust the desired magnification, focus, and examine the sample in the
polarization contrast which is now present while turning the rotary stage Pol (
689H689HFig. 4-15/3).
To Next Page
Loading...
