Optical Filters FAQs

Here we have provided comprehensive lists of commonly asked questions regarding our Semrock optical filters and related applications. This information is designed to support your inquiries, but if you don’t find the answers you are looking for we encourage you to contact us for further assistance.

Please use the sort buttons in the left navigation to navigate between questions and answers that are specific to Optical Imaging Systems, Fluidics, Cameras, Microfluidics, our Webstore, and Engineering Partnership.


What is the lifetime of edge blackening paint on a filter, and are there special methods to clean these filters?

The edge blackening paint is intended to remain adherent to the glass surface for the life of the filter, without decomposing and/or falling off, provided that the paint on the filter edge is neither abraded by an external agent nor dissolved using a chemical agent such as acetone. Examples of suitable use include being stably secured in an assembly or housing with no exposure to such solvents. We have encountered no complaints regarding edge blackening paint from customers whose optical systems with edge blackened filters have been in service for over ten years.

Use isopropyl alcohol (IPA) or methanol to clean edge blackened filters, as these solvents don’t affect the edge blackening paint, provided the cleaning is gentle, i.e., not aggressive or of overly long duration. Do not use acetone, as this will remove the paint.

Learn How to Clean Your Semrock® Optical Filters Without Edge Blackening