Optical Glass Cleaning: Grinding, Coating & De-ink/Strip
Optical glass runs cutting, edging, grinding and polishing; cleaning must match each step, and coatings are highly sensitive to strong alkali.
1Stage-by-stage cleaning
Typical stages are pre-ink, pre-bonding and pre-assembly cleaning. Grinding/polishing leaves cutting fluid, edging oil, slurry and polishing powder; pre-bonding is mostly dust and fingerprints — simpler but requires very high surface cleanliness.
2Protecting the coating
Coatings are vulnerable to strong alkali, so post-coating cleaning must avoid high-alkaline cleaners and use a dedicated post-coating optical cleaner that preserves the film while removing soil. Lenses and filters commonly carry polishing compound and coating residue, typically removed with ultrasonics.
3De-ink & de-strip
Phone/lens glass often needs edge ink removal (de-ink) and coating rework (de-strip). A dual-function bath combines chelation for stripping with penetrating solvent for de-inking; these can also run separately. Strip chemistry must target the film stack (metal/dielectric/AR) without attacking the glass; Ti/Cr films use mild oxidation plus complexation.