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Keywords from Image Description:
WenhamsGlasparaboloidafterHarting. en Scheme of the microscopic darkfield illumination with Wenhams glas paraboloid which was described in Wenham Red and green lines are added to allow better recognition of the beam path shown as it was assumed by Wenham de Schema der Dunkelfeldbeleuchtung mit dem Glasparaboloid nach Wenham Rote