Ultra-smooth reflective components are characterized by high surface accuracy, low surface waviness, no surface flaws, no sub-surface damage, and complete lattice structure.

Ultra-smooth reflective components refer to optical components with a surface roughness of less than 1nm. Due to their ability to accurately reflect and transmit light, they are widely used in high-precision optical systems.

Reflective components have at least one reflective surface, which plays a role in bending the optical path and changing the positive and negative relationship of imaging. Reflective components mainly include three categories: plane reflective components, spherical reflective components, and aspherical reflective components. Plane reflective components have a flat working surface, including single-sided and double-sided types; spherical reflective components have a spherical working surface, including convex spherical and concave spherical types; and aspherical reflective components have a working surface that is neither flat nor spherical, commonly seen as parabolic or hyperbolic surfaces. In comparison, aspherical reflective components are more widely used.

According to the "2024-2029 China Ultra-smooth Reflective Component Industry Market Depth Research and Development Prospects Prediction Report" published by the New Thinktank Industry Research Center, in conventional optical systems, the surface roughness of reflective components is less than 0.012μm, but in high-precision optical systems, the surface roughness requirements for reflective components are extremely high, requiring less than 1nm, i.e., ultra-smooth reflective components. Ultra-smooth reflective components are characterized by high surface accuracy, low surface waviness, no surface flaws, no sub-surface damage, and complete lattice structure.

The application of aspherical ultra-smooth reflective components in optical instruments can improve the optical properties of the system, reduce the volume and weight of the instrument, and are indispensable optical components for realizing X-rays, extreme ultraviolet, intense lasers, etc. They are widely used in the manufacture of instruments and equipment such as telescopes, lasers, microscopes, spectrometers, and semiconductor lithography, with extremely broad market prospects.

The key technology for processing ultra-smooth reflective components is to achieve surface material polishing at the atomic level. Commonly used ultra-smooth reflective component processing technologies mainly include contact polishing methods such as bath polishing and polytetrafluoroethylene polishing, as well as non-contact polishing methods such as float polishing, ion beam polishing, plasma-assisted polishing, elastic emission machining, and magnetorheological polishing. Among them, elastic emission machining and magnetorheological polishing have good competitive advantages in terms of processing component types, component surface accuracy, and sub-surface damage.

The materials for ultra-smooth reflective components can be glass, metal, etc. Metal itself has a high reflectivity, and after being polished into a reflective component, its high reflectivity advantage is prominent, and metal is easy to process and shape. In precision optical instruments, ultra-smooth reflective components with complex surfaces are needed to improve imaging performance and achieve more functions. Therefore, in some application fields, ultra-smooth metal reflective components are expected to replace glass reflective components.

Industry analysts from New Thinktank said that in the key special project of "Basic Scientific Research Conditions and Major Scientific Instrument and Equipment Development" of the 2023 National Key Research and Development Plan released by China's Ministry of Science and Technology, ultra-smooth special reflective components have been included, proposing the development of ultra-smooth special alloy mirrors to achieve small-batch applications in high-end wafer defect detection equipment light source systems and lighting systems. With the promotion of national policies, the development prospects of China's ultra-smooth reflective component industry are broad.