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Today scientists, lab technicians, engineers, and industrial technicians regularly use lasers to perform a wide range of important scientific tasks. They measure distances, both short and long, with lasers, giving astronomers, geographers, and surveyors much more accurate figures than were available before the invention of these devices.

With the help of frequency tuning, spectroscopic studies of various nonlinear optical effects are carried out, and the control of the polarization of laser radiation allows for coherent control of the processes under study.

During the flights to the Moon by manned and unmanned vehicles, several special reflectors were delivered to its surface. A specially focused laser beam was sent from Earth and the precise time it takes to travel to the lunar surface and back was measured. Based on the value of the speed of light, the distance to the moon was calculated.

Using of adaptive optics methods in ground-based telescopes can significantly improve the image quality of astronomical objects by measuring and compensating for optical distortions of the atmosphere. The laser radiation is scattered in the upper layers of the atmosphere, creating a reference light source visible from the earth's surface – an artificial "star". The light from it, which passed through the atmospheric layer on the way back to earth, contains information about optical distortions taking place at a given time. The atmospheric distortions measured in this way are compensated by a special corrector.

Some types of lasers can produce ultrashort light pulses measured in femtoseconds. Such pulses can be used to trigger and analyze chemical reactions. Ultrashort pulses can be used to study chemical reactions with high time resolution, allowing reliable isolation of short-lived compounds. Manipulation of the polarization of the pulse allows you to selectively choose the direction of a chemical reaction from several possible ones (coherent control).

Ultrashort laser pulses are used for ultrafast control of the magnetic state of the material, which is currently the subject of intensive research. Many opto-magnetic phenomena have already been discovered, such as ultrafast demagnetization in 200 femtoseconds, thermal remagnetization by light and non-thermal optical magnetization control via light polarization.

Optical tweezers are a device that allows manipulating microscopic objects using laser light. It allows applying forces from femtonewtons to nanonewtons to dielectric objects and measuring distances from several nanometers. In recent years, optical tweezers have been used to study the structure and
working principle of proteins.

One of the ways to solve the problem of retaining heated plasma in a nuclear reactor may be to use lasers. At the same time, a small volume of fuel is irradiated with powerful laser radiation from all sides for a small period of time.

Laser technologies have been widely used in science and will only develop in the future. New devices using laser radiation will be created, for example, there are already laser microscopes that give a higher resolution compared to optical microscopes that use white light.