Lasers - Revision history

Benjip23: /* Laser Light */

2022-11-29T04:24:47Z

Laser Light

← Older revision		Revision as of 00:24, 29 November 2022
Line 56:		Line 56:
	The second fundamental property of laser light is its '''coherence'''. A light field is coherent when there is a fixed phase relationship between the electric field values at different locations or at different times. [https://www.rp-photonics.com/coherence.html] This property exists for lasers due its generation through stimulated emission. When there is a stimulating agent present, a population of electrons emit photons harmoniously. The emitted photons possess a constant phase relationship with each other in space (a laser's spatial coherence) and time (a laser's temporal coherence). This property is important, as it allows a laser to be focused into a concentrated spot, which is essential for applications like laser cutting and optical communications.		The second fundamental property of laser light is its '''coherence'''. A light field is coherent when there is a fixed phase relationship between the electric field values at different locations or at different times. [https://www.rp-photonics.com/coherence.html] This property exists for lasers due its generation through stimulated emission. When there is a stimulating agent present, a population of electrons emit photons harmoniously. The emitted photons possess a constant phase relationship with each other in space (a laser's spatial coherence) and time (a laser's temporal coherence). This property is important, as it allows a laser to be focused into a concentrated spot, which is essential for applications like laser cutting and optical communications.

	Laser light can also be classified in different modes of operation: '''continuous''', where power output is continuous over time, or '''pulsed''', where its output is comprised of short pulses of light. Continuous-wave operation is significantly harder to achieve compared to pulsed operation, as population inversion of the gain medium must be constantly replenished by a steady pump source.		Laser light can also be classified in different modes of operation: '''continuous''', where power output is continuous over time, or '''pulsed''', where its output is comprised of short pulses of light. Continuous-wave operation is significantly harder to achieve compared to pulsed operation, as population inversion of the gain medium must be constantly replenished by a steady pump source. [https://www.rp-photonics.com/coherence.html]

	===Mathematical Model===		===Mathematical Model===

Benjip23: /* Laser Light */

2022-11-29T04:24:33Z

Laser Light

← Older revision		Revision as of 00:24, 29 November 2022
Line 54:		Line 54:
	[[File:Laser light chars.png\|frame\|Characteristics of laser light vs. ordinary light. [https://www.aspenlaser.com/wp-content/uploads/2017/02/Properties-of-Laser-Light.jpg]]]		[[File:Laser light chars.png\|frame\|Characteristics of laser light vs. ordinary light. [https://www.aspenlaser.com/wp-content/uploads/2017/02/Properties-of-Laser-Light.jpg]]]

	The second fundamental property of laser light is its '''coherence'''. A light field is coherent when there is a fixed phase relationship between the electric field values at different locations or at different times. [~~ref here~~] This property exists for lasers due its generation through stimulated emission. When there is a stimulating agent present, a population of electrons emit photons harmoniously. The emitted photons possess a constant phase relationship with each other in space (a laser's spatial coherence) and time (a laser's temporal coherence). This property is important, as it allows a laser to be focused into a concentrated spot, which is essential for applications like laser cutting and optical communications.		The second fundamental property of laser light is its '''coherence'''. A light field is coherent when there is a fixed phase relationship between the electric field values at different locations or at different times. [https://www.rp-photonics.com/coherence.html] This property exists for lasers due its generation through stimulated emission. When there is a stimulating agent present, a population of electrons emit photons harmoniously. The emitted photons possess a constant phase relationship with each other in space (a laser's spatial coherence) and time (a laser's temporal coherence). This property is important, as it allows a laser to be focused into a concentrated spot, which is essential for applications like laser cutting and optical communications.

	Laser light can also be classified in different modes of operation: '''continuous''', where power output is continuous over time, or '''pulsed''', where its output is comprised of short pulses of light. Continuous-wave operation is significantly harder to achieve compared to pulsed operation, as population inversion of the gain medium must be constantly replenished by a steady pump source.		Laser light can also be classified in different modes of operation: '''continuous''', where power output is continuous over time, or '''pulsed''', where its output is comprised of short pulses of light. Continuous-wave operation is significantly harder to achieve compared to pulsed operation, as population inversion of the gain medium must be constantly replenished by a steady pump source.

Benjip23: /* Gain Media & Amplification */

2022-11-29T04:23:56Z

Gain Media & Amplification

← Older revision		Revision as of 00:23, 29 November 2022
Line 28:		Line 28:

	===Gain Media & Amplification===		===Gain Media & Amplification===
	As stated, the gain medium is the source for optical gain within a laser. In order for the process of light amplification to occur, the gain medium is put into an excited state by an external source of energy, or a '''pump source'''. Pump sources usually take the form of an electric current or another form of light, and are necessary to achieve population inversion for the system of particles, as the energy produced from pump sources is actively absorbed into the medium. [wikipedia ~~active laser medium ref here~~] As a consequence of such, an important requirement for pump sources is that the input pump power must be greater than the lasing threshold for the laser - the lowest excitation level at which a laser's output is primarily a function of stimulated emission instead of spontaneous emission. [wikipedia ~~laser pumping ref here~~]		As stated, the gain medium is the source for optical gain within a laser. In order for the process of light amplification to occur, the gain medium is put into an excited state by an external source of energy, or a '''pump source'''. Pump sources usually take the form of an electric current or another form of light, and are necessary to achieve population inversion for the system of particles, as the energy produced from pump sources is actively absorbed into the medium. [https://en.wikipedia.org/wiki/Active_laser_medium] As a consequence of such, an important requirement for pump sources is that the input pump power must be greater than the lasing threshold for the laser - the lowest excitation level at which a laser's output is primarily a function of stimulated emission instead of spontaneous emission. [https://en.wikipedia.org/wiki/Laser_pumping]

	[[File:Energy-level-amplification.png\|frame\|An energy level transition diagram for three & four level systems [https://www.researchgate.net/figure/Energy-level-diagrams-for-optical-gain-media-a-Energy-level-and-transitions-of-a_fig2_349256243]]]		[[File:Energy-level-amplification.png\|frame\|An energy level transition diagram for three & four level systems [https://www.researchgate.net/figure/Energy-level-diagrams-for-optical-gain-media-a-Energy-level-and-transitions-of-a_fig2_349256243]]]

Benjip23: /* Mathematical Model */

2022-11-29T04:21:50Z

Mathematical Model

← Older revision		Revision as of 00:21, 29 November 2022
Line 68:		Line 68:
	[[File:Gaus_distr.png\|200px\|frame\|The instantaneous absolute value of the real part of the electric field amplitude of a gaussian beam focal region[https://en.wikipedia.org/wiki/Gaussian_beam]]]		[[File:Gaus_distr.png\|200px\|frame\|The instantaneous absolute value of the real part of the electric field amplitude of a gaussian beam focal region[https://en.wikipedia.org/wiki/Gaussian_beam]]]
	[[File:GaussianBeamWaist.svg.png\|frame\|Gaussian beam width <math>\omega(z)</math> as a function of distance z. [https://en.wikipedia.org/wiki/Gaussian_beam]]]		[[File:GaussianBeamWaist.svg.png\|frame\|Gaussian beam width <math>\omega(z)</math> as a function of distance z. [https://en.wikipedia.org/wiki/Gaussian_beam]]]
	[[File:~~Gaus_w~~.png\|frame\|Beam radius of Gaussian beam (blue), with two vertical lines being Rayleigh length and dashed lines showing asymptotic behavior far from beam waist. [https://www.rp-photonics.com/gaussian_beams.html]]]		[[File:Gaus_w_2.png\|frame\|Beam radius of Gaussian beam (blue), with two vertical lines being Rayleigh length and dashed lines showing asymptotic behavior far from beam waist. [https://www.rp-photonics.com/gaussian_beams.html]]]

	where		where

Benjip23: /* Mathematical Model */

2022-11-29T04:19:40Z

Mathematical Model

← Older revision		Revision as of 00:19, 29 November 2022
Line 68:		Line 68:
	[[File:Gaus_distr.png\|200px\|frame\|The instantaneous absolute value of the real part of the electric field amplitude of a gaussian beam focal region[https://en.wikipedia.org/wiki/Gaussian_beam]]]		[[File:Gaus_distr.png\|200px\|frame\|The instantaneous absolute value of the real part of the electric field amplitude of a gaussian beam focal region[https://en.wikipedia.org/wiki/Gaussian_beam]]]
	[[File:GaussianBeamWaist.svg.png\|frame\|Gaussian beam width <math>\omega(z)</math> as a function of distance z. [https://en.wikipedia.org/wiki/Gaussian_beam]]]		[[File:GaussianBeamWaist.svg.png\|frame\|Gaussian beam width <math>\omega(z)</math> as a function of distance z. [https://en.wikipedia.org/wiki/Gaussian_beam]]]
	[[File:Gaus_w.png~~\|200px~~\|frame\|Beam radius of Gaussian beam (blue), with two vertical lines being Rayleigh length and dashed lines showing asymptotic behavior far from beam waist. [https://www.rp-photonics.com/gaussian_beams.html]]]		[[File:Gaus_w.png\|frame\|Beam radius of Gaussian beam (blue), with two vertical lines being Rayleigh length and dashed lines showing asymptotic behavior far from beam waist. [https://www.rp-photonics.com/gaussian_beams.html]]]

	where		where

Benjip23: /* Mathematical Model */

2022-11-29T04:18:04Z

Mathematical Model

← Older revision		Revision as of 00:18, 29 November 2022
Line 68:		Line 68:
	[[File:Gaus_distr.png\|200px\|frame\|The instantaneous absolute value of the real part of the electric field amplitude of a gaussian beam focal region[https://en.wikipedia.org/wiki/Gaussian_beam]]]		[[File:Gaus_distr.png\|200px\|frame\|The instantaneous absolute value of the real part of the electric field amplitude of a gaussian beam focal region[https://en.wikipedia.org/wiki/Gaussian_beam]]]
	[[File:GaussianBeamWaist.svg.png\|frame\|Gaussian beam width <math>\omega(z)</math> as a function of distance z. [https://en.wikipedia.org/wiki/Gaussian_beam]]]		[[File:GaussianBeamWaist.svg.png\|frame\|Gaussian beam width <math>\omega(z)</math> as a function of distance z. [https://en.wikipedia.org/wiki/Gaussian_beam]]]
	[[File:Gaus_w.png\|frame\|Beam radius of Gaussian beam (blue), with two vertical lines being Rayleigh length and dashed lines showing asymptotic behavior far from beam waist. [https://www.rp-photonics.com/gaussian_beams.html]]]		[[File:Gaus_w.png\|200px\|frame\|Beam radius of Gaussian beam (blue), with two vertical lines being Rayleigh length and dashed lines showing asymptotic behavior far from beam waist. [https://www.rp-photonics.com/gaussian_beams.html]]]

	where		where

Benjip23: /* Mathematical Model */

2022-11-29T04:17:41Z

Mathematical Model

← Older revision		Revision as of 00:17, 29 November 2022
Line 68:		Line 68:
	[[File:Gaus_distr.png\|200px\|frame\|The instantaneous absolute value of the real part of the electric field amplitude of a gaussian beam focal region[https://en.wikipedia.org/wiki/Gaussian_beam]]]		[[File:Gaus_distr.png\|200px\|frame\|The instantaneous absolute value of the real part of the electric field amplitude of a gaussian beam focal region[https://en.wikipedia.org/wiki/Gaussian_beam]]]
	[[File:GaussianBeamWaist.svg.png\|frame\|Gaussian beam width <math>\omega(z)</math> as a function of distance z. [https://en.wikipedia.org/wiki/Gaussian_beam]]]		[[File:GaussianBeamWaist.svg.png\|frame\|Gaussian beam width <math>\omega(z)</math> as a function of distance z. [https://en.wikipedia.org/wiki/Gaussian_beam]]]
			[[File:Gaus_w.png\|frame\|Beam radius of Gaussian beam (blue), with two vertical lines being Rayleigh length and dashed lines showing asymptotic behavior far from beam waist. [https://www.rp-photonics.com/gaussian_beams.html]]]

	where		where

Benjip23: /* Mathematical Model */

2022-11-29T04:14:50Z

Mathematical Model

← Older revision		Revision as of 00:14, 29 November 2022
Line 66:		Line 66:
	<math>I(r,z) = \frac{2P_{0}}{\pi{}\omega{}(z)^2}exp(\frac{-2r^2}{\omega{}(z)^2})</math>		<math>I(r,z) = \frac{2P_{0}}{\pi{}\omega{}(z)^2}exp(\frac{-2r^2}{\omega{}(z)^2})</math>

	[[File:Gaus_distr.png\|200px\|frame\|The instantaneous absolute value of the real part of the electric field amplitude of a gaussian beam focal region]]		[[File:Gaus_distr.png\|200px\|frame\|The instantaneous absolute value of the real part of the electric field amplitude of a gaussian beam focal region[https://en.wikipedia.org/wiki/Gaussian_beam]]]
			[[File:GaussianBeamWaist.svg.png\|frame\|Gaussian beam width <math>\omega(z)</math> as a function of distance z. [https://en.wikipedia.org/wiki/Gaussian_beam]]]

	where		where

Benjip23: /* Mathematical Model */

2022-11-29T04:06:37Z

Mathematical Model

← Older revision		Revision as of 00:06, 29 November 2022
Line 66:		Line 66:
	<math>I(r,z) = \frac{2P_{0}}{\pi{}\omega{}(z)^2}exp(\frac{-2r^2}{\omega{}(z)^2})</math>		<math>I(r,z) = \frac{2P_{0}}{\pi{}\omega{}(z)^2}exp(\frac{-2r^2}{\omega{}(z)^2})</math>

	[[File:Gaus_distr.png\|frame~~\|200px~~\|The instantaneous absolute value of the real part of the electric field amplitude of a gaussian beam focal region]]		[[File:Gaus_distr.png\|200px\|frame\|The instantaneous absolute value of the real part of the electric field amplitude of a gaussian beam focal region]]

	where		where

Benjip23: /* Mathematical Model */

2022-11-29T04:06:20Z

Mathematical Model

← Older revision		Revision as of 00:06, 29 November 2022
Line 66:		Line 66:
	<math>I(r,z) = \frac{2P_{0}}{\pi{}\omega{}(z)^2}exp(\frac{-2r^2}{\omega{}(z)^2})</math>		<math>I(r,z) = \frac{2P_{0}}{\pi{}\omega{}(z)^2}exp(\frac{-2r^2}{\omega{}(z)^2})</math>

	[[File:Gaus_distr.png\|frame\|The instantaneous absolute value of the real part of the electric field amplitude of a gaussian beam focal region]]		[[File:Gaus_distr.png\|frame\|200px\|The instantaneous absolute value of the real part of the electric field amplitude of a gaussian beam focal region]]

	where		where