flashbulbs

Flashbulbs are disposable photographic light sources used to illuminate a scene for a brief moment during a photograph. They consist of a small sealed glass envelope containing a pyrotechnic composition and a triggering mechanism. When fired, the composition burns rapidly, producing a bright flash of light and often causing the envelope to rupture.

In operation, a camera triggers a detonator at the bulb’s base. The detonator ignites the pyrotechnic material, generating an intense burst of light within a few milliseconds. Because the chemical reaction consumes the entire contents of the bulb, the device is designed for single use and must be discarded after firing.

Flashbulbs were widely adopted in the mid-20th century and became common in news, fashion, and documentary photography. They offered a compact, self-contained light source and consistent brightness, and did not require a separate power pack. Their popularity declined with the rise of electronic flash units and digital cameras in the latter part of the century.

Safety concerns included the hot, explosive reaction inside the bulb and the risk of premature ignition or shattering, which could cause injury or start fires. Handling, storage, and disposal required care; today, unused flashbulbs are rare outside specialized or retro equipment collections.

By the late 20th century, flashbulbs largely disappeared from mainstream photography, though the term remains used to describe the old technology and is sometimes referenced in discussions of photographic history and vintage equipment.