DISCO DAD 2H/6T, Troubleshooting Manual

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J-2
1. When Dust and Contamination become Obstacles to Observation
(Including Viewing Impaired by fogginess):
1-1. Objective Lens
- When non-transmission phenomenon with white or blue color occurs at the surface of the objective lens;
[Cause] This phenomenon is caused by corrosion of the coated surface of the lens and degradation of the
lens material.
[Remedy] Detach the objective lens and check the transmittance of the lens using light from a light bulb or
the like. If the lens surface does not become transparent after it is cleaned with lens paper and a
solvent, the lens should be replaced. However, the adjustments after this replacement require
special procedures so that we recommend you contact out service division or the like for
replacement.
- When peeling-off materials are seen at the periphery of the lens;
[Cause] This phenomenon is caused by separation of the adhesive (Fig. J-1).
Fig. J-1
[Remedy] The lens should be replaced. Replacement must be done by the manufacturer.
- When the lens moves within the case;
[Cause] This is caused by looseness of the screw ring which fixes the lens within the case.
[Remedy] Tightening of the lens nut (also called the screw ring) is required. This adjustment requires
skilled operation; tighten the lens nut as little as possible and lock the screw ring to fix the lens.
Do not over-tighten the lens nut.
1-2. Ocular Lens
-
When dust and contamination are seen at the ocular lens part;
[Cause] This is caused by dust and contamination in the environment.
[Remedy] The lens part and the scale part should be cleaned.
Note: The cleaning method of the lens and the prism will be described at the end of this manual.
If there is no problem in 1-1 and 1-2, but dust and contamination are observed through the ocular lens,
adjustment should be made according to the following procedures.
1-3. Contamination of the Surface of the Split Prism
-
Contamination of split prism surface;
[Cause] It results from a foul operating environment.
[Remedy] Clean the split prism surface. It must be returned to the manufacturer for repair.
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