<div style="text-align: justify;">The KF-4U4.2 condenser is purposed for research of transparent low-contrast objects with biological and polarization microscopes in transmitted light. The phase contrast condenser allows to obtain contrast areas in the image of the object depending on their optical density or thickness. It allows to observe a positive phase contrast in very thin specimens. It can be used in medical and biological science labs, especially for research of living objects.<br /><br />The condenser turret contains circular diaphragms which image is projected onto phase ring of an objective. This provides effect of phase contrast in the image. Best results can be achieved with a green filter placed below the condenser.<br /><br />The condenser allows also to observe objects in bright field without phase contrast (with empty turret slot and iris diaphragm).<br /><br />In order to align a phase ring with a circular diaphragm, it is necessary to use a phase telescope instead of usual eyepiece.<br /><br />The condenser numeric aperture is 0.9<br />Mount diameter is 37mm.<br /></div><br />