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[[განივი ტალღა]] არის ისეთი ვექტორული ტალღა, რომლის ამპლიტუდა '''k''' ტალღური ვექტორის პერპენდიკულარულია, ხოლო [[გრძივი ტალღა]] კი არის ტალღა რომელშიც ამპლიტუდის ვექტორი '''k'''-ს პარალელურია.
ზემოთ მოყვანილ განტოლებაში ფუნქცია ''ω''('''k''') არის [[დისპერსიული თანაფარდობა]]. ფარდობა ''ω''/|'''k'''| არის [[ფაზური სიჩქარე|ფაზური სიჩქარის]] მოდული, ხოლო ''dω''/''d'''''k''' არის [[ჯგუფური სიჩქარე]].
In this equation, the function ''ω''('''k''') is the [[dispersion relation]] of the medium, with the ratio ''ω''/|'''k'''| giving the magnitude of the [[phase velocity]] and ''dω''/''d'''''k''' giving the [[group velocity]]. For electromagnetism in an isotropic medium with index of refraction ''n'', the phase velocity is ''c''/''n'', which equals the group velocity only if the index is not frequency-dependent.
ზოგადად, ტალღური განტოლების ნებისმიერი ამონახსენი შეიძლება წარმოდგენილი იქნას როგორც ბრტყელი ტალღების სუპერპოზიცია.
Generally, a wave solution can be expressed as a superposition of plane waves. This approach is known as the [[Angular spectrum method]]. The form of the planewave solution is actually a general consequence of [[translational symmetry]]. More generally, for [[Periodicity|periodic]] structures having discrete translational symmetry, the solutions take the form of [[Bloch wave]]s, most famously in [[crystal]]line atomic materials but also in [[photonic crystal]]s and other periodic wave equations. As another generalization, for structures that are only uniform along one direction ''x'' (such as a [[waveguide]] along the ''x'' direction), the solutions (waveguide modes) are of the form exp[''i''(''kx''-''ωt'')] multiplied by some amplitude function ''a''(''y'',''z''). This is a special case of a [[separable partial differential equation]].
The term is used in the same way for [[telecommunication]], e.g. in [[Federal Standard 1037C]] and [[MIL-STD-188]].
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=== Polarized electromagnetic plane waves ===
{{multiple image
| direction = vertical
| footer = The blocks of vectors represent how the magnitude and direction of the electric field is constant for an entire plane perpendicular to the direction of travel.
| footer_align = left
| width =
| image1 = Linear.Polarization.Linearly.Polarized.Light_plane.wave.svg
| width1 = 450
| caption1 = Linearly polarized light.
| image2 = Circular.Polarization.Circularly.Polarized.Light_plane.wave_Right.Handed.svg
| width2 = 450
| caption2 = Circularly polarized light.
| image3 =
| image4 =
}}
Represented in the first illustration toward the right is a [[linear polarization|linearly polarized]], [[electromagnetic wave|electromagnetic wave]]. Because this is a plane wave, each blue [[Euclidean_vector|vector]], indicating the perpendicular displacement from a point on the axis out to the sine wave, represents the magnitude and direction of the [[electric field]] for an entire plane that is perpendicular to the axis.<br/>
Represented in the second illustration is a [[circular polarization|circularly polarized]], electromagnetic plane wave. Each blue vector indicating the perpendicular displacement from a point on the axis out to the helix, also represents the magnitude and direction of the electric field for an entire plane perpendicular to the axis.<br/>
In both illustrations, along the axes is a series of shorter blue vectors which are scaled down versions of the longer blue vectors. These shorter blue vectors are extrapolated out into the block of black vectors which fill a volume of space. Notice that for a given plane, the black vectors are identical, indicating that the magnitude and direction of the electric field is constant along that plane.<br/>
In the case of the linearly polarized light, the field strength from plane to plane varies from a maximum in one direction, down to zero, and then back up to a maximum in the opposite direction.<br/>
In the case of the circularly polarized light, the field strength remains constant from plane to plane but its direction steadily changes in a rotary type manner.
Not indicated in either illustration is the electric field’s corresponding [[magnetic field]] which is proportional in strength to the electric field at each point in space but is at a right angle to it. Illustrations of the magnetic field vectors would be virtually identical to these except all the vectors would be rotated 90 degrees perpendicular to the direction of propagation.
== იხილეთ აგრეთვე ==
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