Parylene’s Optical Properties and Performance

Parylene is a reliable, protective, conformal film that safeguards printed circuit boards (PCBs), similar electronic assemblies and other products. Parylene generates advantageous optical properties for a wide range of uses, including artwork/museum artifacts, cameras/sensors, computer touchscreens, healthcare/medical devices, light-emitting diode systems (LEDs), lenses and optoelectronic components.
            
It should be noted that while the thinnest Parylene films (<1 um.) offer unblemished optical clarity, increased coating thickness can slightly mar visual acuity. Parylene layer application rarely exceeds 25 microns, assuring these minor visual alterations remain mostly undetectable; for practical purposes, the coating’s dependable visual perception will be retained. In addition, the type of Parylene used for coating will impact optical clarity, according to film thickness. Parylene C, for instance, is optically clear while Parylene N displays minute surface haze at thicknesses > 5 μm. Visually insignificant, these optical variances persist across XY types, as coating thickness increases.