50 free Laser trivia questions with answers — technology quiz, new questions added Aug 2026.
This laser trivia quiz covers the beam from Einstein's 1917 theory to the fusion shot that finally broke even in 2022. The easy questions ask what the acronym stands for, who built the first working laser and in what year, what the maser amplified before light, which gemstone crystal made that first beam and which James Bond villain aimed one at 007. From there it moves through the people who fought over the credit, the gas and diode lasers that followed, and the everyday machines that quietly rely on lasers: barcode scanners, CD players, printers and eye surgery. The hard end is for people who know their population inversion from their optical pumping: the graduate student who had his notebook notarised in a candy store, the journal that rejected Maiman twice, the supermarket that scanned the first pack of gum, the mirror Apollo 11 left behind, the 192 beams of the National Ignition Facility, the Nobel for cooling atoms with light and the wavelength of the light inside every CD player. Every answer was checked against the encyclopaedia entries on the laser, maser, Theodore Maiman, Charles Townes, Gordon Gould, the ruby laser, LASIK, laser printers, lidar, LIGO, the National Ignition Facility, barcodes, compact discs and Goldfinger before publishing, and the supporting sentence is stored with each question. Our inventions, physics and light quizzes are natural next stops.
30 of 50 questions with answers and explanations. Play the quiz
Q 01The word 'laser' began as an acronym. What does the 'S' and 'E' part stand for?
Stimulated emission
The full phrase is 'light amplification by stimulated emission of radiation'; a joker once noted 'LOSER' (light oscillation) would be more accurate.
Q 02Who built the first working laser, in 1960?
Theodore Maiman
He did it at Hughes Research Laboratories in Malibu, beating rival teams at Columbia, Bell Labs and TRG.
Q 03The first working laser used a synthetic crystal of which gemstone as its lasing medium?
Ruby
A flashlamp pumped the crystal to produce red light at 694 nanometres, in pulses only.
Q 04The maser, the laser's predecessor, amplified what kind of radiation?
Microwaves
Early lasers were briefly called 'optical masers' before 'microwave' was swapped for 'light' in the acronym.
Q 05Which physicist laid the theoretical foundations for the laser in a 1917 paper on the quantum theory of radiation?
Albert Einstein
His coefficients for absorption, spontaneous emission and stimulated emission are still called Einstein coefficients.
Q 06Charles Townes shared the 1964 Nobel Prize in Physics with two scientists from which country?
Soviet Union
Nikolay Basov and Aleksandr Prokhorov solved the problem of continuous output by using more than two energy levels.
Q 07Gordon Gould, who coined the term 'laser' in his 1957 notebook, took the notebook where to have it notarised?
A neighbourhood store
That notebook launched a 28-year patent fight; he did not win a significant infringement claim until 1987.
Q 08Gould's 1959 paper intended different acronyms for different parts of the spectrum. What did he propose for X-rays?
XASER
'UVASER' was for ultraviolet and 'RASER' for radio waves; instead 'laser' swallowed everything shorter than microwaves.
Q 09How long did Gordon Gould's legal fight over laser patent rights last after the patent office turned him down in 1960?
Twenty-eight years
Historians still regard the question of who invented the laser as unresolved, since so many parts were patented by different people.
Q 10Maiman's paper announcing the first laser was published in Nature in August 1960 after how many rejections from Physical Review Letters' editor?
Two
Townes later called it 'probably more important per word than any of the papers published by Nature over the past century'.
Q 11Later in 1960, Ali Javan and colleagues built the first gas laser using which two gases, and it could run continuously?
Helium and neon
Most HeNe lasers are engineered to lase at 633 nm, the familiar red beam of school physics labs.
Q 12The first semiconductor laser, demonstrated by Robert N. Hall in 1962, was made of which material?
Gallium arsenide
It emitted near-infrared light at 850 nm and only worked in pulses while cooled with liquid nitrogen.
Q 13The carbon-dioxide laser, invented by C. Kumar N. Patel in 1964, emits in which part of the spectrum?
Thermal infrared
Q 21Which type of beam is used in LASIK surgery to reshape the cornea?
Excimer
These ultraviolet lasers are also used to print microchips by photolithography.
Q 22Which type is by far the most commonly manufactured, found in barcode readers, pointers and disc drives?
Diode
They also carry the world's fibre-optic internet traffic.
Q 23The word 'lidar', first recorded as a stand-alone word in 1963, is thought to have begun as a portmanteau of which two words?
Light and radar
It measures range by timing how long laser light takes to bounce back, and now guides self-driving cars.
Its 10.6 μm beam and unusually high efficiency of over 30% made it a workhorse for industrial cutting and welding.
Q 14The active ingredient in a ruby laser's crystal is ions of which element suspended in synthetic sapphire?
Chromium
Those chromium ions are also what make natural ruby red.
Q 15When it was first invented, the laser was famously described as what?
A solution looking for a problem
Gould's notebook had already listed telecommunications, radar, spectrometry and nuclear fusion as possible uses.
Q 16What was the first widely noticeable everyday use of lasers, introduced in 1974?
Supermarket barcode scanners
The first item scanned was a pack of Wrigley's chewing gum at a Marsh supermarket in Troy, Ohio.
Q 17The first product ever scanned with a UPC barcode, in June 1974, was a pack of what?
Chewing gum
It happened at a Marsh supermarket in Troy, Ohio, using a scanner made by Photographic Sciences Corporation.
Q 18Which product, introduced in 1978, was the first successful consumer device to include a laser?
The laserdisc player
The CD player, commercialised in 1982, was the first laser-equipped device to become truly common.
Q 19A compact disc is read by a semiconductor laser of what wavelength, in the near infrared?
780 nm
Early players used a helium-neon laser instead; Blu-ray players use a 405 nm violet laser.
Q 20The laser printer was invented in 1969 by Gary Starkweather at which company?
Xerox
His idea was to use a laser beam to 'draw' the image directly onto a copier drum.
Q 24Lunar laser ranging bounces beams off a retroreflector array left on the Moon by which mission on 21 July 1969?
Apollo 11
Those measurements show the Moon is spiralling away from Earth at 3.8 centimetres a year.
Q 25Laser ranging to the Moon shows it is drifting away from Earth at roughly what rate?
3.8 cm per year
The retroreflectors placed by Apollo astronauts and Soviet Lunokhod rovers still return photons today.
Q 26The National Ignition Facility at Lawrence Livermore focuses how many laser beamlines onto its fuel target?
192
They are flashlamp-pumped, neodymium-doped phosphate glass lasers, and the whole system is the most energetic laser in the world.
Q 27On 5 December 2022 the National Ignition Facility achieved what long-sought milestone?
Scientific breakeven for fusion
The shot yielded 154% of the laser energy that went in, though far less than the electricity used to power the lasers.
Q 28LIGO, which uses laser interferometers to detect gravitational waves, has L-shaped vacuum arms of what length?
4 km
Its two observatories are in Hanford, Washington, and Livingston, Louisiana; Europe's Virgo detector has 3 km arms.
Q 29LIGO's first detection, on 14 September 2015, came from the merger of two of what?
Black holes
Each was about 30 solar masses; the discovery was announced in February 2016 and won the 2017 Nobel Prize in Physics.
Q 30The 1997 Nobel Prize in Physics went to Steven Chu, Claude Cohen-Tannoudji and William Phillips for using lasers to do what?
Cool and trap atoms
Laser cooling slows atoms to a crawl by hitting them with photons tuned just below their absorption frequency.