Phase masks

Also often known as FBG Phase masks, Ibsen offers +1/-1 order Phase masks for replicating Bragg grating structures into fibers (FBGs) and waveguides. Holographic production techniques yield Phase masks that are inherently free of stitching errors, and provide continuous, linear chirp as an option. Period accuracy and uniformity is better than 0.01 nm. Phase masks are custom produced, with 0. order suppressed for the required illumination wavelength and polarization. Each Phase mask has identifying parameters individually specified on the Phase mask substrate.

Also known as NFH Phase masks, Ibsen offers 0/-1 order Phase masks which are ideal for writing grating periods that, as a rule of thumb, are less than twice the illumination wavelength, in which case the 0. order of a +1/-1 order Phase mask cannot be well suppressed. For wafer-based grating production, the Nearfield Holography (NFH) technique is ideal in a production environment as it employs a mask aligner approach. A mask aligner specially modified for the technology is commercially available from Suss MicroTec. Ibsen offers 0/-1 order Phase masks with periods down to 260 nm.

Phase masks may become contaminated during use – an effective cleaning process is important in ensuring longest possible lifetime of the Phase mask. Ibsen offers Cleaning Services for your Phase masks, optionally with an extensive evaluation of the Phase mask defect level before and after cleaning.