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The operating principle of an outdoor lens hood

Release Date:

2021-06-30 10:22

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The operating principle of an outdoor lens hood

　　A lens hood serves to block stray light; for example, it’s used on smartphone camera lenses and other camera lenses. It’s a Mylar‑based element mounted within the lens. Because its primary function is to reduce glare, it’s commonly referred to as a lens hood or a light‑blocking shim.

　　Working principle:

　　Its operating principle is based on the physical phenomenon of pinhole imaging, and its manufacturing requirements are quite stringent. Consequently, it places relatively high demands on the materials used.

　　By employing proprietary technology, the light‑shading ring undergoes a specialized blackening treatment that delivers excellent electrical conductivity, complete opacity, and a double‑sided matte finish. It offers precise tolerances and superior mechanical properties. Made from brass, it is highly versatile in machining—capable of producing flared, stepped, and other configurations—and exhibits outstanding high‑temperature resistance. A secondary coating process yields an even deeper black hue, making it ideal for optical components requiring precise light attenuation. The blackening film boasts strong adhesion, superior corrosion resistance, and enhanced wear resistance, making it suitable for producing high‑quality blackened finishes on a wide range of copper and copper‑alloy parts. The process generates no harmful gases; the blackening solution is nearly neutral, non‑corrosive, and free of heavy metals and toxic selenium compounds.

How can the scrap rate of Mylar films be reduced?

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