Phase Mask Cleaning

Recommended Procedure for Regular Phase Mask Cleaning

Even with proper handling, all precision optical components will need cleaning from time to time. Adhering to proper cleaning procedures will lengthen the lifetime of the component. The complex surface structure of Phase masks places special requirements on the nature of the cleaning process.


Avoid all physical contact with the grating area. This includes dragging lens tissue across the grating side of the Phase mask, as residue may be deposited in the grating structure of the Phase mask. Many lab detergents will also leave residue behind, and should therefore also be avoided.

Convenient Cleaning

There is a commercially available optics cleaning product – “First Contact” – on the market. This cleaning product is effective for many optics cleaning requirements. Ibsen has tested it’s applicability to Phase masks and can furthermore confirm that it does not damage the grating. For further information on First Contact, please see This cleaning method is recommended as it does not require chemical cleaning which always has risk of leaving residue

Traditional Cleaning Procedure

Use the following gentle cleaning procedure to remove grease and loose particles:

  1. Agitate the Phase Mask in a Petri dish filled with Semiconductor Grade Acetone. Ensure that the acetone does not dry out before step 2.
  2. Agitate the Phase Mask in a Petri dish filled with Semiconductor Grade Isopropanol Alcohol or Semiconductor Grade Ethanol. Ensure again that the fluid does not dry out before step 3.
  3. Agitate the Phase Mask in a Petri dish filled with ultra-pure water.
  4. If available, spin drying is optimal. Otherwise, blow dry (preferably in a cleanroom environment) with clean air (maximum pressure 2 bar).

Special Cleaning Procedure

If a more effective cleaning process is required, Ibsen offers a cleaning service, which includes a proprietary cleaning process. Contact us for more information on this service.