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...Optical and manufacturing processes considerations when designing with glass molded optics written by amber luttmann december introduction in modern design the tried true method for creating lenses surfaces is through grinding polishing technology very large numbers of spherical flat parts can be made high precision quickly at low cost this standard fabrication however once aspheric are needed these methods become much more involved a normally numerous different milling techniques frequent monitoring surface to create proper shape dramatically increases production time where molding pgm used allow rapid repeatable cheap paper will discuss process as well outline some basic guidelines their systems that utilize them while have many advantages should weighed against costs before deciding use an system moldable first step discussing using what how it from typical glasses traditional main characteristic defines its transition temperature or tg lower than c heated expands but past certain b...