TERMIUM Plus^®

Record 1,  Textual support,  English

Record number: 1, Textual support number: 1 CONT

Under thermodynamic equilibrium conditions, almost all atoms or molecules are in the ground state and so it requires more than half of this number to be excited out of the ground state to achieve laser action. This implies that a much larger pumping input would be required to exceed population inversion threshold.  1, record 1, English, - population%20inversion%20threshold

Record 1,  Textual support,  French

Record number: 1, Textual support number: 1 CONT

Le seuil d'inversion de population est d'autant plus bas que la fréquence du rayonnement est faible.  2, record 1, French, - seuil%20d%27inversion%20de%20population

Record 1,  Textual support,  Spanish

Record 2,  Textual support,  English

Record number: 2, Textual support number: 1 DEF

A laser is which the active medium is a discharge in a gas contained in a glass or quartz tube with a Brewster-angle window at each end.  2, record 2, English, - gas%20laser

Record number: 2, Textual support number: 1 OBS

The gas can be excited by a high-frequency oscillator or direct-current flow between electrodes inside the tube.  2, record 2, English, - gas%20laser

Record number: 2, Textual support number: 2 OBS

The function of the discharge is to pump the medium, to obtain population inversion.  2, record 2, English, - gas%20laser

Record 2,  Textual support,  French

Record number: 2, Textual support number: 1 CONT

Laser à gaz. [...] Le gaz [...] est contenu dans un tube cylindrique étanche ou vide, en verre, en silice fondue ou en matériaux réfractaires [...]. Le plus souvent ce tube est fermé aux deux extrémités par des fenêtres planes placées sous incidence brewstérienne [...].  2, record 2, French, - laser%20%C3%A0%20gaz

Record 2,  Textual support,  Spanish

Record 3,  Textual support,  English

Record number: 3, Textual support number: 1 DEF

an optical oscillator or amplifier employing as the active medium a forward biased semiconductor diode in which a population inversion has been established between the conduction band and valence band.  2, record 3, English, - injection%20laser

Record 3,  Textual support,  French

Record 3,  Textual support,  Spanish

Record 4,  Textual support,  English

Record number: 4, Textual support number: 1 CONT

Continuous-Wave Lasers.... Often it is desirable to have a continuous laser beam rather than a series of pulses, in which case pumping energy must be put in continuously to maintain a population inversion.  4, record 4, English, - continuous%2Dwave%20laser

Record number: 4, Textual support number: 2 CONT

Continuous-wave lasers have been employed as a "light knife," that is a surgical cutting and coagulation tool.  5, record 4, English, - continuous%2Dwave%20laser

Record number: 4, Textual support number: 3 CONT

[The laser airspeed indicator] employs a continuous-wave laser focused on a specific plane at the required distance ahead of the aircraft.  6, record 4, English, - continuous%2Dwave%20laser

Record number: 4, Textual support number: 1 OBS

Although "continuously operating laser" is found in at least two sources, it seems more of an explanation of the function of a laser rather than a definite term.  7, record 4, English, - continuous%2Dwave%20laser

Record 4,  Textual support,  French

Record number: 4, Textual support number: 1 DEF

Oscillateur dont la puissance ne varie pas au cours du temps.  4, record 4, French, - laser%20continu

Record number: 4, Textual support number: 1 CONT

Un laser continu peut servir comme une sorte de scalpel lumineux incisant les tissus par brûlure.  5, record 4, French, - laser%20continu

Record number: 4, Textual support number: 2 CONT

[L'indicateur de vitesse à laser] repose sur l'emploi d'un faisceau laser à onde entretenue dont le foyer est fixé à la distance voulue en avant de l'avion.  6, record 4, French, - laser%20continu

Record 4,  Textual support,  Spanish

Record number: 4, Textual support number: 1 DEF

Láser constituido por una envuelta de cuarzo rellena de una mezcla de helio y neón a baja presión con espejos de Breuster en sus extremos y un sistema óptico exterior.  2, record 4, Spanish, - l%C3%A1ser%20de%20funcionamiento%20continuo

Record number: 4, Textual support number: 1 OBS

[Este dispositivo produce un] foco de luz coherente [que emplea] un sólido cristalino (por ejemplo un rubí) o un tubo de descarga de gases en el cual son inyectados átomos simultáneamente en estados excitados por una descarga de luz incoherente. Estos vuelven a su estado estable con emisión de un impulso de luz cuyo flujo de energía puede ser de 10 mw/cm².  1, record 4, Spanish, - l%C3%A1ser%20de%20funcionamiento%20continuo

Record number: 4, Textual support number: 2 OBS

El primer láser de funcionamiento continuo fue el láser de gas producido por Bell Telephone Laboratory (1960) en el cual se aplicaba una descarga de baja energía, en una mezcla de gases helio y neón, para producir un haz muy definido e intenso de radiaciones infrarrojas.  1, record 4, Spanish, - l%C3%A1ser%20de%20funcionamiento%20continuo

Record 5,  Textual support,  English

Record number: 5, Textual support number: 1 CONT

When more molecules(atoms, ions) in a laser are in a metastable state than in the ground state(a situation needed for sustaining a high rate of stimulated emissions), a "population inversion" is said to exist. Without a population inversion, there can be no lasing action.  2, record 5, English, - population%20inversion

Record 5,  Textual support,  French

Record number: 5, Textual support number: 1 DEF

Inversion des conditions d'équilibre thermique due à un changement de l'état énergétique du semi-conducteur; la probabilité d'occupation de la bande de conduction est supérieure à celle de la bande de valence.  2, record 5, French, - inversion%20de%20population

Record 5,  Textual support,  Spanish

Record 6,  Textual support,  English

Record number: 6, Textual support number: 1 OBS

fiber optics  1, record 6, English, - energy%20population%20inversion

Record 6,  Textual support,  French

Record number: 6, Textual support number: 1 CONT

L'inversion de population a lieu lorsque les atomes d'erbium de la fibre sont pompés à un niveau très élevé d'énergie par le rayonnement d'excitation.  1, record 6, French, - inversion%20de%20population

Record 6,  Textual support,  Spanish

Record 7,  Textual support,  English

Record number: 7, Textual support number: 1 CONT

energy can be extracted in the form of a laser beam by putting resonator mirrors on each side of the place where the population inversion exists in the flowing gas.  2, record 7, English, - resonator%20mirror

Record 7,  Textual support,  French

Record 7,  Textual support,  Spanish

Record 8,  Textual support,  English

Record number: 8, Textual support number: 1 DEF

the output of a laser when the cavity resonator "Q" is initially kept very low so that a much larger population inversion than that which normally characterizes laser operation is achieved.  2, record 8, English, - Q%2Dswitched%20pulse

Record 8,  Textual support,  French

Record 8,  Textual support,  Spanish

Record 9,  Textual support,  English

Record number: 9, Textual support number: 1 DEF

A nonequilibrium condition that exists when there are more atoms in the excited state than in the ground state.  1, record 9, English, - population%20inversion

Record 9,  Textual support,  French

Record number: 9, Textual support number: 1 CONT

Pour observer véritablement une amplification de l'onde incidente (...) il faut produire une inversion des populations, c'est-à-dire réaliser des conditions spéciales où les atomes à l'état d'énergie supérieure sont plus nombreux que les atomes à l'état inférieur (...)  1, record 9, French, - inversion%20des%20populations

Record 9,  Textual support,  Spanish