The Luminaphone of 1926 was one of a long line of inventions by the British inventor Harry Grindell Matthews, well known at the time for his much publicised invention of a ‘Death Ray’ in 1923 – an unsubstantiated or proven method of destroying objects and stopping electric engines through an invisible ray-gun. Matthew’s roster of inventions included a light controlled submarine (from which he received a £25,000 prize from the British admiralty), a mobile projector for projecting images onto clouds, an early method of recording sound on to film (1921), an underwater submarine detector, ground-to-plane radio-telephone, and a self-righting flying machine, amongst many others.
The Luminaphone, patented in 1925 (Patent GB254437A ), was an early example of a photo-electric technique for creating pitched tones (originally derived from optical sound film technology); in this case a series of light beams – each light beam representing one frequency or note – were projected through a rotating perforated metal dome onto a selenium photo-cell that generated a pitched voltage pulse. The frequency of the pitch was determined by the frequency of the perforation in the metal dome. The luminaphone’s three octave keyboard had one lamp per key (a total of 36 keys and lamps) – when a key was pressed the assigned lamp would illuminate and project through the rotating perforated dome onto the photo-cell, generating the relevant pitch.
The size and shape of the perforations determined the pitch, intensity and tone quality of the instruments tone – although, presumably, this would require stopping the machine and manually changing the rotating dome to change the sound or intensity.
Matthews planned to produce a commercial version of the instrument but the Luminaphone never evolved beyond the one prototype model.
Harry Grindell Matthews. Biographical Details:
Harry Grindell Matthews. born on 17 March 1880, at Winterbourne, South Gloucestershire.UK. Died:11 September 1941, Swansea, Wales UK.
Harry Grindell Matthews, a prolific British inventor, became an electronic engineer while serving in the Second Boer War (1900). Matthews many and often fantastical inventions provoked controversy due to his penchant for publicity and unwillingness to reveal his methods – most famously with his military ‘Death Ray’ gun of 1923.
After being rejected by the British military, Matthews travelled to France with the apparent aim of selling his Death Ray invention to the French army and after he was again rejected he travelled to the USA with his new invention, the Luminaphone, to raise funds and generate publicity for his new projects. In 1938 Matthews married the (extremely wealthy) Polish opera singer Ganna Walska and constructed a well protected laboratory and airstrip in Tor Clawdd north of Swansea in the South Wales hills. Matthews later projects included liquid fuelled rockets and a high flying ‘Stratoplane’. Matthews died of a heart attack on 11 September 1941 before any of his inventions were put into practical production.
UK Patent GB254437A.
‘Popular Science’ Magazine March 1926 p55
‘The Light Beam Piano’; Science and Invention. USA. magazine February 1926. P896
‘Lichtstrahlen Musik’ Illustrierte Technik für Jedermann: Heft 18 1926 p199