METAL REFLECTION IMMERSION GRATING WITH LOW POLARIZATION AND HIGH DIFFRACTION EFFICIENCY, AND OPTICAL SYSTEM

摘要

Disclosed are a metal reflection immersion grating with a low polarization and a high diffraction efficiency, and an optical system. The grating comprises: a grating layer comprising a plurality of first slots arranged in an array; a dielectric layer, which covers the surface of the grating layer at an equal thickness, the thickness of the dielectric layer being less than the depth of the slot of the grating layer, and a second slot being formed in a surface of the dielectric layer; and a metal reflection layer located on the side of the dielectric layer that is away from the grating layer, one side of the metal reflection layer filling the second slot, wherein a first interface is formed between the grating layer and the dielectric layer, and a second interface is formed between the dielectric layer and the metal reflection layer; and incident light is incident, through the interior of the grating layer, to the first interface, a diffraction effect arises between the first interface, the dielectric layer and the second interface so as to generate diffracted light, and the diffracted light is reflected from the metal reflection layer and is emergent from the interior of the grating layer. The grating can achieve a low polarization and a high diffraction efficiency, can reduce the difficulty of a manufacturing process, and has an important application value in the field of high-resolution atmospheric sounding.