Editing List of inventors (section)

===L===
* [[Dmitry Lachinov]] (1842–1902), Russia – [[mercury (element)|mercury]] [[pump]], [[economizer]] for electricity consumption, [[Insulator (electrical)|electrical insulation]] tester, [[optical]] [[dynamometer]], [[photometer]], [[Electrolysis|electrolyser]]
* [[René Laennec]] (1781–1826), France – [[stethoscope]]
* [[Georges Lakhovsky]] (1869–1942), Russia/U.S. – multiple wave oscillator
* [[Simon S. Lam]] (born 1947) U.S. – [[Secure Network Programming|Secure Sockets]] invented in 1991 for securing Internet applications (World Wide Web, email, etc.)
* [[Hedy Lamarr]] (1914–2000), Austria and U.S. – [[Spread spectrum]] radio
* [[Edwin H. Land]] (1909–1991), U.S. – [[Polaroid Corporation|Polaroid]] polarizing filters and the [[Land Camera]]
* [[Samuel P. Langley]] (1834–1906), U.S. – [[bolometer]]
* [[Alexander Nikolayevich Lodygin]] (1847–1923), [[Russia]] – [[incandescent lamp]]
* [[Irving Langmuir]] (1851–1957), U.S. – gas filled [[incandescent light bulb]], hydrogen welding
* [[Norm Larsen]] (1923–1970), U.S. – [[WD-40]]
* [[Lewis Latimer]] (1848–1928), U.S. – improved carbon-filament light bulb
* [[Gustav de Laval]] (1845–1913), Sweden – invented the milk separator and the milking machine
* [[Semyon Lavochkin]] (1900–1960), Russia – [[Lavochkin|La]]-series aircraft, first operational [[surface-to-air missile]] [[S-25 Berkut]]
* [[John Bennet Lawes]] (1814–1900), UK – [[superphosphate]] or [[chemical fertilizer]]
* [[Ernest Lawrence|Ernest Orlando Lawrence]] (1901–1958), U.S. – [[Cyclotron]]
* [[Nikolai Lebedenko]], Russia – [[Tsar Tank]], largest [[armored vehicle]] in history
* [[Sergei Vasiljevich Lebedev|Sergei Lebedev]] (1874–1934), Russia – commercially viable [[synthetic rubber]]
* [[William Lee (inventor)|William Lee]] (1563–1614), UK – [[Stocking frame]] [[knitting machine]]
* [[Edward Leedskalnin]] (1887–1951), U.S. – construction techniques used to single-handedly lift massive coral blocks in the creation of his [[Coral Castle]]
* [[Antoni van Leeuwenhoek]] (1632–1723), The Netherlands – development of the [[microscope]]
* [[Jerome H. Lemelson]] (1923–1997), U.S. – inventions in the fields in which he patented make possible, wholly or in part, innovations like automated warehouses, [[industrial robots]], [[cordless telephones]], [[fax machines]], videocassette recorders, [[camcorders]], and the [[magnetic tape drive]] used in Sony's Walkman tape players.
* [[Etienne Lenoir|Jean-Joseph Etienne Lenoir]] (1822–1900), Belgium – [[internal combustion engine]], [[motorboat]]
* [[Giacomo da Lentini]] (13th century), Italy – [[Sonnet]]
* [[R. G. LeTourneau]] (1888–1969), U.S. – electric wheel, motor scraper, mobile oil drilling platform, bulldozer, cable control unit for scrapers
* [[Rasmus Lerdorf]] (born 1968), Greenland/Canada – [[PHP]] (programming language)
* [[Willard Frank Libby]] (1908–1980), U.S. – [[radiocarbon dating]]
* [[Justus von Liebig]] (1803–1873), Germany – [[nitrogen]]-based [[fertilizer]]
* [[Edward Light]] (1747–1832), UK – [[harp lute]]
* [[Hon Lik]] (born 1951), China – [[electronic cigarette]]
* [[Otto Lilienthal]] (1848–1896), Germany – [[hang gliding|hang glider]]
* [[Lin Yutang]] (1895–1976), China/U.S. – [[Chinese typewriter|Chinese language typewriter]]
* [[Charles Lindbergh]] (1902–1974), U.S. – organ [[perfusion]] pump
* [[Frans Wilhelm Lindqvist]] (1862–1931), Sweden – Kerosene stove operated by compressed air
* [[Carl Linnaeus]] (1707–1778), Sweden – formal [[Binomial nomenclature]] for living organisms, [[Linnaeus' flower clock|Horologium Florae]]
* [[Hans Lippershey]] (1570–1619), The Netherlands – associated with the appearance of the [[telescope]]
* [[Gabriel Lippmann|Jonas Ferdinand Gabriel Lippmann]] (1845–1921), France – [[Lippmann plate]], [[Integral imaging]], [[Lippmann electrometer]]
* [[Lisitsyns|Lisitsyn]] brothers, Ivan Fyodorovich and Nazar Fyodorovich, Russia – [[samovar]] (the first documented makers)
* [[William Howard Livens]] (1889–1964), UK – chemical warfare – [[Livens Projector]]
* [[Eduard Locher]] (1840–1910), Switzerland – [[Rack railway#Locher|Locher rack railway system]]
* [[Fredrik Ljungström]] (1875–1964) and [[Birger Ljungström]] (1872–1948), Sweden – [[Ljungström turbine]], [[Ljungström air preheater]], [[Ljungström method]]
* [[Alexander Lodygin]] (1847–1923), Russia – [[electrical filament]], [[incandescent light bulb]] with tungsten filament
* [[Louis Lombard-Gérin]] (1848–1918), France – [[trolleybus]]
* [[Mikhail Lomonosov]] (1711–1765), Russia – [[night vision telescope]], [[off-axis reflecting telescope]], [[coaxial rotor]], re-invented [[smalt]]
* [[Yury Lomonosov]] (1876–1952), Russia/UK – first successful mainline [[diesel locomotive]]
* [[Aleksandr Loran]] (1849 – after 1911), Russia – [[fire fighting foam]], [[Fire extinguisher#Foams|foam extinguisher]]
* [[Oleg Losev]] (1903–1942), Russia – [[light-emitting diode]], [[crystadine]]
* [[Antoine Louis]] (1723–1792), France – [[Guillotine]]
* [[Archibald Low]] (1882–1956), UK – pioneer of radio guidance systems
* [[Ed Lowe (businessman)|Ed Lowe]] (1920–1995), U.S. – [[Cat litter]]
* [[Gleb Lozino-Lozinskiy]] (1909–2001), Russia – [[Buran (spacecraft)]], [[Mikoyan-Gurevich MiG-105|Spiral project]]
* [[Ignacy Łukasiewicz]] (1822–1882), Poland/Armenia – [[Kerosene lamp]], [[Oil refinery]]
* [[Auguste and Louis Lumière]] (1862–1954 and 1864–1948), France – [[Cinématographe]]
* [[Cai Lun]], 蔡倫 (50–121), China – [[paper]]
* [[Giovanni Luppis]] or Ivan Vukić (1813–1875), [[Austrian Empire]] (ethnical Croatian, from Rijeka) – self-propelled [[torpedo]]
* [[Gustave Lyon]] (1857–1936), France – [[Cross-strung harp|chromatic harp]]
* [[Richard F. Lyon]] (born 1952), U.S. – [[Optical mouse]]
* [[Arkhip Mikhailovich Lyulka|Arkhip Lyulka]] (1908–1984), Russia – first double jet [[turbofan]] engine, [[Lyulka|other]] Soviet [[aircraft engine]]s