Low and high beam headlights history and development

Discover the history of low and high beam headlights, from the first dipped beam in 1915 to modern adaptive lighting technologies.

When we switch on the headlights, it feels like something that has always been there. Yet the story of low and high beams is one of engineering ingenuity, regulatory battles, and gradual refinements stretching back more than a century.

The journey began in the late 19th century: in 1898 the Columbia Electric offered electric headlamps as an option, and by 1912 Cadillac had integrated a full Delco electrical system with starter and lighting. That milestone laid the foundation for real innovation in beam control.

In 1915, Guide Lamp introduced the idea of “dipping” the headlamps. The beam could be tilted downward to reduce glare for oncoming drivers, though at first motorists had to step out of the car to adjust them manually. Just two years later, in 1917, Cadillac made the process practical: a lever inside the cabin allowed the driver to switch between positions without leaving the seat.

The breakthrough came in 1924–1925 with dual-filament bulbs. Sources differ: some histories cite 1924, but OSRAM’s official records point to a 1925 world premiere of the BILUX™ lamp in Berlin. In the same year, Guide Lamp launched its own Duplo version. This marked the birth of the modern concept of combining low and high beams in one bulb.

Convenience took another leap in 1927 with the arrival of the foot-operated dip switch, which soon became a fixture in cars worldwide. After that, regulation played a major role. The U.S. mandated 7-inch sealed beams in 1940, then allowed four 5¾-inch lamps from 1957. Europe went a different way, approving the first halogen H1 in 1962, setting the stage for brighter, more efficient light.

By the late 20th century, progress accelerated: halogen gave way to HID, then to LEDs, and now adaptive systems dominate. High-Beam Assist and Adaptive Driving Beam technologies automatically shape the beam, dimming only the segments that might dazzle oncoming drivers while maintaining range.

Looked at in sequence, the milestones are clear: 1915 — dipped beam, 1917 — cabin lever, 1925 — dual filament, 1927 — foot switch, 1940 and 1957 — sealed beam standards, 1962 — halogens. From there, the story moves into the era of smart electronics.

Today, as we marvel at matrix LEDs and adaptive lighting, it’s easy to forget that it all began with one simple idea: don’t blind the driver coming toward you. More than a century later, that principle still defines automotive lighting.