Reflective diffraction grating and fabrication method

A method of fabrication, the method comprising:

• providing a substrate;
• depositing an ultraviolet (UV)-absorbing layer, configured as a single layer made of a UV-absorbing dielectric material and for absorbing light at a UV recording wavelength to minimize reflection thereof,
• the UV-absorbing dielectric layer having a thickness of at least 1.2 μm,
• the UV-absorbing dielectric material having a transmission intensity of less than 25% at the UV recording wavelength,
• the UV recording wavelength being between 300 nm and 450 nm, and
• the UV-absorbing dielectric material being disposed directly on the substrate and separate from the substrate;
• and
• forming a reflective grating directly on the UV-absorbing dielectric material,
• the UV recording wavelength being different from an operating wavelength for the reflective grating.