Leica DMI4000B, DMI3000B manual Troubleshooting Problem Cause/Remedy Phase contrast, Polarization

9. Troubleshooting

Problem Cause/Remedy

Phase contrast

No phase contrast is possible.

￿The specimen is too thick.

￿The cover glass is not placed evenly. ￿Check the centering of the light rings

(→ p. 73).

Polarization

No polarization contrast is possible.

￿Bring the polarizer and analyzer into cross po- sition until they reach maximum darkness (without specimen).

(→ p. 86).

Transmitted light interference contrast

No transmitted light interference contrast is	￿The specimen is too thick or too thin.
possible	￿Embedding medium or specimen are of bire-
	fringent material. Rotate the specimen.
	￿The difference in the refractive indices of the
	specimen and the embedding medium is too
	small.
	￿The cover glass is too thick.
	￿Check the Koehler illumination (→ p. 69).
	￿Bring the polarizer and analyzer into cross po-
	sition until they reach maximum darkness
	(without specimen).
	(→ p. 87).
	￿Check whether the suitable condenser prism
	and corresponding objective prism are se-
	lected (manual alternative → p. 87).
	￿Ensure that the IC prisms are correctly seated
	(→ p. 40).

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