Physical world and mathematics

Laser Doppler velocimetry

Laser Doppler velocimetry is an optical technique that measures fluid velocity at a point from the Doppler shift of laser light scattered by tracer particles, first demonstrated in 1964.

Laser Doppler vibrometer

A laser Doppler vibrometer, or LDV, is a non-contact optical instrument measuring the velocity of vibrating surfaces, from MEMS devices to bridges, via the Doppler shift of laser light.

Laser excitation of thorium-229 isomer

Laser excitation of thorium-229 isomer is the resonant optical driving of the low-lying excited nuclear state of thorium-229, first achieved in 2024 and the basis for proposed nuclear clocks.

Laser flash analysis

Laser flash analysis is a fast, non-contact method that heats a small disk with a laser pulse and records the rear-face temperature rise to measure thermal diffusivity.

A laser interferometer is a measurement instrument that determines distance or displacement by counting interference fringes of laser light, used to calibrate machines and enabling LIGO's gravitational-wave detection.

Laser Interferometer Space Antenna

The Laser Interferometer Space Antenna (LISA) is an ESA-led space gravitational-wave observatory with NASA participation, planned to launch in 2035 with three spacecraft flying 2.5 million km apart.

Laser interferometric displacement measurement

Laser interferometric displacement measurement determines changes in position by counting laser interference fringes; displacement measuring interferometers, sold since the early 1970s, are the reference standard for dimensional calibration.

Laser interferometry

Laser interferometry is a measurement technique that determines distance or displacement by counting and interpolating interference fringes of laser light, underpinning top-level length metrology in industry and science.

Laser linewidth

Laser linewidth is the width of a laser's optical spectrum, reported as full width at half maximum and serving as a measure of the laser's phase noise.

Laser linewidth measurement

Laser linewidth measurement is the experimental determination of the spectral width of a laser's optical emission, set mainly by phase jitter, using interferometric and phase-noise techniques.

Laser mass spectrometry

Laser mass spectrometry is an umbrella term for mass spectrometry methods using lasers to desorb, ablate, or ionize samples, including MALDI, LIMS, and laser ablation ICP-MS.

Laser medicine

Laser medicine, also called laser therapy, is the use of lasers to diagnose and treat disease, most often by cutting, destroying, or coagulating tissue or activating light-sensitive drugs.

Laser pointer

A laser pointer, also called a laser pen, is a hand-held laser used to point during lectures, astronomy, and construction; US regulation limits visible output to 5 milliwatts.

Laser rangefinder

A laser rangefinder, also called a laser distance meter, measures distance by timing a laser pulse's round trip to a target, from handheld meters to satellite altimeters.

Laser ranging

Laser ranging measures distances by firing short laser pulses at retroreflector-equipped satellites, the Moon, or spacecraft and timing the reflected light, underpinning Earth's reference frame and tests of general relativity.

Laser safety

Laser safety, also called laser radiation safety, is the practice of preventing eye and skin injury from laser radiation through classification, controls, and protective eyewear.

Laser threshold

The laser threshold is the point at which laser emission just begins, where the active medium's gain equals the cavity's total loss; below it the device only amplifies.

Laser tracker

A laser tracker is a portable coordinate measuring instrument that follows a reflective target with a laser beam, measuring 3D positions tens of meters away to tens-of-micrometers accuracy.

Laser wakefield acceleration

Laser wakefield acceleration (LWFA), proposed by Tajima and Dawson in 1979, uses intense laser pulses to drive plasma waves whose teravolt-per-meter fields accelerate electrons compactly.

Laser wire (accelerator diagnostics)

A laser wire is a non-invasive accelerator beam profile monitor that scans a finely focused laser across a charged particle beam to measure its transverse size.

Laser-assisted synthesis

Laser-assisted synthesis is a family of materials chemistry methods using laser irradiation to form nanomaterials, thin films, or compounds, best developed as laser synthesis and processing of colloids.

Laser-driven gamma-ray source

A laser-driven gamma-ray source produces MeV gamma rays by directing intense laser pulses onto matter, mainly through inverse Compton scattering, bremsstrahlung, or betatron radiation, aiming at compact, high-brightness sources.

Laser-driven ion acceleration

Laser-driven ion acceleration produces fast ion beams by striking thin foil or gas targets with ultraintense laser pulses, pursued as a compact alternative to conventional accelerators.

Laser-driven ion acceleration with relativistic transparency

Laser-driven ion acceleration with relativistic transparency is a laser-plasma regime in which relativistic electron motion makes a solid target transparent, letting the pulse deposit energy throughout and accelerate ions to higher energies.

Laser-driven magnetic field generation

Laser-driven magnetic field generation is a high-energy-density physics technique in which an intense laser pulse striking a capacitor-coil target generates quasi-static magnetic fields approaching kilotesla strength.

Laser-driven neutron source

A laser-driven neutron source (LDNS) is a device that produces neutrons with a high-power laser, offering compactness, short pulses, and transportability for imaging, materials science, and security screening.

Laser-driven proton radiography

Laser-driven proton radiography is an imaging diagnostic in which an intense laser pulse on a thin metal foil accelerates protons through an object to image its electromagnetic fields.

Laser-free trapped-ion qubit control

Laser-free trapped-ion qubit control performs quantum logic gates on trapped ions using microwaves, radiofrequency signals, and magnetic or electric field gradients rather than precisely aligned laser beams.

Laser-induced breakdown spectroscopy

Laser-induced breakdown spectroscopy (LIBS) is an atomic emission technique in which a laser pulse forms a plasma, determining elemental composition with little sample preparation, even at standoff distances.