Hidden headlamps are an automotive styling feature that conceals an automobile's headlamps when they are not in use. Depending on the design, the headlamps may be mounted in a housing that rotates so as to sit flush with the front end as on the Porsche 928), may retract into the hood and/or fenders as on the 1968 - 2004 Chevrolet Corvette, or may be concealed behind retractable or rotating grille panels as on the 1966 Dodge Charger.
Hidden headlamps first appeared on the Cord 810 in 1936. Each unit had a crank on its side of the dashboard which had to be turned by hand when the headlamps needed to be used.
Powered hidden headlamps were pioneered in GM's Buick Y-Job concept car of 1938 and were used briefly on Chrysler Corporation's 1942 production DeSoto. The feature's popularity has waxed and waned over time. Hidden headlamps regained popularity in the late 1960s, particularly in the US market where aerodynamic headlamps were not permitted. A relatively large variety of cars incorporated hidden headlamps in the 1970s, '80s, and early 1990s. Currently, hidden headlamps have fallen out of favour.
Numerous car manufacturers used hidden headlamps to get around the headlight height regulation in the United States, for instance Toyota exported their retractable headlight version of the AE86, known domestically as the Sprinter Trueno in favour of their Corolla Levin as the former had higher headlamp height, enough to satisfy US regulations rather than raise body height which affected handling.
US laws now permit aerodynamic headlamps, relative to which hidden headlamps represent added cost, weight, and complexity as well as reliability concerns as cars age. Internationalized ECE auto safety regulations have also recently incorporated pedestrian-protection provisions restricting protuberances from car bodies, making it more difficult and expensive to design compliant pop-up headlamps.
The last time pop-up headlamps appeared on a volume-production car was in 2004 when both the Lotus Esprit and C5 Corvette ended production.
