English Dictionary

sealed beam

noun

(technology) A type of electric lamp for producing a beam of light in which the filament is sealed inside a unit consisting of the reflector and lens so as to ensure the alignment of the beam and to protect the reflector from becoming dirty or tarnished.

I replaced the sealed beam in my car's headlight.

意味（1）

(technology) A type of electric lamp for producing a beam of light in which the filament is sealed inside a unit consisting of the reflector and lens so as to ensure the alignment of the beam and to protect the reflector from becoming dirty or tarnished.

The new Sealed Beam Headlights are designed to maintain substantially their initial efficiency throughout their life.