What is the function of a lens hood?
Release Date:
2021-06-30 11:13
Source:
A light‑blocking ring serves to prevent stray light; for example, it’s used in smartphone camera lenses and other imaging optics. It’s manufactured by stamping SOMA light‑blocking material and then embedded as a Mylar sheet within the lens assembly. Because of its light‑blocking function, it’s commonly referred to as a light‑blocking ring or a light‑blocking shim.

A lens hood serves to block stray light—for example, the lens hood on a smartphone camera or on a camera lens.
It is a Mylar sheet stamped from SOMA light‑blocking material and mounted inside the lens. Because it serves to block stray light, it is commonly referred to as a light‑blocking ring or a light‑blocking shim.
Its operating principle is based on the physical phenomenon of pinhole imaging, and its manufacturing requirements are quite stringent. Consequently, it places high demands on the materials used; in the market, Japanese SOMA light‑blocking material is predominantly employed—a double‑matte black PET film.
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