High heat copolycarbonate compositions having enhanced optical properties, articles formed therefrom, and methods of manufacture

A copolycarbonate lens formed from a polycarbonate composition comprising: a copolycarbonate comprising bisphenol A carbonate units and of phthalimide carbonate and optionally, a bisphenol A homopolycarbonate; wherein the second carbonate units are present in an amount of 18 to 35 mol % based on the sum of the moles of the copolycarbonate and the bisphenol A homopolycarbonate, the copolycarbonate comprises less than 2 ppm by weight of each of an ion of lithium, sodium, potassium, calcium, magnesium, ammonium, chlorine, bromine, fluorine, nitrite, nitrate, phosphite, phosphate, sulfate, formate, acetate, citrate, oxalate, trimethylammonium, and triethylammonium, as measured by ion chromatography, and the polycarbonate composition has a bisphenol A purity of at least 99.7% as determined by high performance liquid chromatography. The polycarbonate composition has: a Vicat B120 of 155° C. or higher; and an increase in yellowness index of less than 10 during 1000 hours of heat aging at 155° C.