A device for preparing an ensemble of laser-cooled atoms and measuring their population includes a laser and a set of reflecting surfaces. The laser is able to produce a laser beam. The set of reflecting surfaces disposed to direct the laser beam along a multi-dimensional beam path to intersect a central space multiple times from different directions and retroreflect the laser beam to retrace the multi-dimensional beam path. The central space is able to have an ensemble of atoms or molecules. The atoms or the molecules are able to be cooled along one or more dimensions by the laser beam sent along the multi-dimensional beam path and able to be detected in the central space by an effect upon the laser beam sent along the multi-dimensional beam path.

The present invention relates to a device for converting a frequency of an electromagnetic wave and, more specifically, to a device for converting an original frequency of an electromagnetic wave into a frequency corresponding to a resonator mode by using a time-varying Fabry-Perot resonator including a time-varying reflective surface of which reflectivity changes with time. A device for converting a frequency of an electromagnetic wave according to an embodiment of the present invention comprises: a time-varying reflective surface on which an electromagnetic wave is incident and of which reflectivity changes with time; and a partially reflective surface which is disposed at a predetermined distance from the time-varying reflective surface, from which an electromagnetic wave having a frequency corresponding to a resonator mode is emitted, and which has a fixed reflectivity for partially reflecting the electromagnetic wave incident through the time-varying reflective surface, wherein the reflectivity of the time-varying reflective surface is smaller than the reflectivity of the partially reflective surface, and after the electromagnetic wave is trapped between the time-varying reflective surface and the partially reflective surface, the reflectivity of the time-varying reflective surface becomes greater than the reflectivity of the partial reflective surface.

In one embodiment, a laser system includes a seed laser configured to produce optical seed pulses. The laser system also includes a first fiber-optic amplifier configured to amplify the seed pulses by a first amplifier gain to produce a first-amplifier output that includes amplified seed pulses and amplified spontaneous emission (ASE). The laser system further includes a first optical filter configured to remove from the first-amplifier output an amount of the ASE. The laser system also includes a second fiber-optic amplifier configured to receive the amplified seed pulses from the first optical filter and amplify the received pulses by a second amplifier gain to produce output pulses. The output pulses have output-pulse characteristics that include: a pulse repetition frequency of less than or equal to 100 MHz; a pulse duration of less than or equal to 20 nanoseconds; and a duty cycle of less than or equal to 1%.

Proposed is a laser apparatus capable of replacing laser wavelengths, and more specifically, a laser apparatus capable of replacing laser wavelengths that includes a plurality of laser output modules which output laser beams having different wavelengths from each other and enables a wavelength of an output laser beam to be changed by switching between the plurality of laser output modules. The laser apparatus capable of replacing laser wavelengths includes: a portable main body having a battery; a laser output module that is detachably coupled to the main body and outputs a laser beam; and a head cover that is detachably coupled to a front side of the laser output module by a magnetic force. The main body has a plurality of ball plungers, and the laser output module has one coupling location adjusting groove into which all of the plurality of ball plungers are inserted.

A laser system includes one or more harmonic generator blocks or elements including one or more crystals for converting a first wavelength (1) laser beam into second, third and/or fourth wavelength (2, 3 and/or 4) laser beams that may be output, with or without the first wavelength (1) laser beam, on different beam paths. One or more of the first, second, third and/or fourth wavelength laser beams may travel or traverse in a crystal in one or multiple directions.

A wavelength measurement apparatus includes a first spectrometer that has a first free spectral range and generates a first measured waveform from an interference pattern produced by a pulse laser beam, a second spectrometer that has a second free spectral range narrower than the first free spectral range and generates a second measured waveform from the interference pattern produced by the pulse laser beam, and a processor that reads data on a first measurement range of the first spectrometer, sets a second measurement range of the second spectrometer based on the data on the first measurement range, reads data on the second measurement range, and calculates a center wavelength of the pulse laser beam based on the data on the first measurement range and the data on the second measurement range.

In various embodiments, a laser emitter such as a diode bar is cooled during operation via jets of cooling fluid formed by ports in a cooler on which the laser emitter is positioned. The jets strike an impingement surface of the cooler that is thermally coupled to the laser emitter but prevents direct contact between the cooling fluid and the laser emitter itself.

The present invention provides systems and methods for optical frequency comb generation with self-generated optical harmonics in mode-locked lasers for detecting the carrier envelope offset frequency. The mode-locked laser outputs an optical frequency comb and a harmonic output. The harmonic output provides an optical heterodyne resulting in a detectable beat note. A carrier envelope offset frequency detector detects the beat note and generates an optical frequency comb signal. The signal can be used to stabilize the optical frequency comb output.

An optical signal transmitter includes a laser source configured to generate light with different wavelengths, respectively; a wavelength division (WD) demultiplexer configured to redirect the light in different directions based on the different wavelengths, respectively; and a lens array including an array of lenses configured to collimate the light from the WD demultiplexer for transmission in different directions, respectively. The optical signal transmitter may be implemented in a light detection and ranging (LIDAR) apparatus. The optical signal transmitter may further include a 1xN splitter and a set of WD demultiplexers to increase the number of distinct optical signal transmissions.

Provided is a laser resonator for generating a laser light by absorbing energy from outside. The laser resonator includes a metal body and a gain medium layer having a ring shape. The gain medium layer of a ring shape may be provided on the metal body and may generate the laser light by a plasmonic effect.