Ikhebula le-Optical, itheyiphu yokuphrinta yepayipi akufanele ibe nokuvuza okunamathelayo, indawo ebushelelezi, unqenqema olucocekile, akukho burr nokuxebuka, amandla aqinile ≥2.5N, izinga lokushisa lokudlulisa ngokuvamile licishe libe ngu-60℃-90℃, lingashintshwa ngokuvumelana nesimo sangempela. yokukhiqizwa kwamakhasimende.