Death ray

A death ray is a theoretical particle beam or electromagnetic weapon concept that emerged in the 1920s and 1930s and has remained largely a subject of fiction and speculation. Several inventors of the era claimed to have built one, including Guglielmo Marconi and Nikola Tesla, who made claims independently, the Britain based inventor Harry Grindell Matthews, who tried unsuccessfully to sell his version to the Air Ministry in 1924 without ever demonstrating a working device, the San Francisco inventor Edwin R. Scott, who claimed priority in 1923, and Erich Graichen, who made a similar claim. While the classic death ray of these decades never proved real, the idea eventually helped inspire genuine military research into directed energy weapons, and in 2014 the United States Navy deployed its Laser Weapon System, a real directed energy weapon that traces its conceptual lineage back to this early twentieth century speculation, even though it works on very different principles from what the original claimants described.