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...How to turn your microscope into a phase contrast gerard t hooft institute for theoretical physics utrecht university postbox tb the netherlands e mail g thooft uu nl internet http www sta science abstract many microscopic samples are highly transparent so that they produce little when viewed in an ordinary however often do producesmallphaserotations duetolocalvariationsoftheindexofrefraction is technique dierences of light intensity it was invented by frits zernike revolutionary invention earned him nobel prize he achieved variations seen accurately represent shifts here i ask simpler question if just want what easiest way accomplish this given very mundane short treatise illustrate method found student my indeed produced impressive images september themethodproposedhere at rst sight seems be not much more than somewhat unusual illuminate object from back while avoiding direct enter eye piece imagineasmallopaque black diskattachedinthemiddleoftheobjectivelens then whenilluminatinganob...