A photon sieve is an optical device used in the field of optics and imaging. It's designed to focus and shape light, typically for applications such as imaging or microscopy. The photon sieve operates on the principle of diffraction, utilizing an array of precisely positioned openings (or pinholes) that allow only certain diffracted orders of light to pass through while blocking others.
In contrast to conventional lenses that use refraction to bend light, a photon sieve uses diffraction to create a pattern of constructive and destructive interference, forming a focused image. The arrangement of pinholes in a photon sieve is carefully calculated to produce the desired diffraction pattern.
Photon sieves are particularly useful in situations where traditional lenses may be impractical due to their size, weight, or complexity. They have found applications in areas such as astronomy, where they can be used in telescopes, and in high-resolution imaging systems.