Phenomena classics of interaction between cancellation and matter

1) Conditions of connection for the electromagnetic fields:

 

2) transparent dielectric Means:

A dielectric is said transparent if not there are phenomena of absorption of the cancellation or, in analytical terms us, if its refractive index is a real number.

 

3) refraction and reflection, Angle of incidence:

The angle of incidence is the angle formed from the cancellation incident with the normal school to the separation surface, it is equal to the reflection angle. The refraction angle is the angle formed from the cancellation that penetrates in according to means with the normal school to the separation surface, is legacy to the angle of incidence from the law of Snell.

 

4) Relation between the wavelengths of the wave incident and the rifratta wave :

 

5) Law of the reflection :

The reflection angle is equal to the angle of incidence.

 

6) Law of Snell :

The product of the breast of the angle of incidence for the refractive index of means 1 is equal to the product of the breast of the angle of refraction for the refractive index of means 2, in formulas .

 

7) Reflection total and angle limit :

If means 2 are those rifrangente n₂ > n_{the 1} then rifratta wave exist always and it is approached the normal school, if instead

n₂ < n_{the 1} rifratta wave is approached the separation surface and for angles q_i greater of the angle limit total is had reflection.

 

8) Principle of Fermat :

The distance followed from the light in order to go from the point To to the B point is what it renders minimum the time of distance.

 

9) Plan of incidence :

It is characterized from the direction of propagation that is from the carrier k, and the orthogonal payer n to the separation surface.

 

10)  :

It indicates a wave polarized linearly in orthogonal direction to the incidence plan.

 

11)  :

It indicates a wave polarized linearly in direction parallel to the incidence plan.

 

12) Relations of Fresnel for normal polarization to the incidence plan :

They are gained imposing that to the passage from means to an other conserves component and and the member parallel

 

13) Relations of Fresnel for polarization parallel to the incidence plan :

They are gained imposing that to the passage from means to an other conserves and_// and B_^ .

 

14) Riflettanza :

It is the relationship between the intensity of the reflected wave and the intensity of the wave incident, is obtained elevating to the square the relationship between the fields of the relations of Fresnel.

 

15) Trasmittanza :

It is the relationship between the intensity of the rifratta wave and the intensity of the wave incident, is obtained elevating to the square the relationship between the fields of the relations of Fresnel.

 

16) Wave not polarized :

A wave is said polarized if the carrier and does not have members of equal effective value in all the directions, it can be obtained like combination of a linearly polarized wave and a wave polarized in parallel with the incidence plan. The values of the riflettanza and the trasmittanza are obviously e

 

17) Angle of Brewster :

Draft of the angle above which the riflettanza parallel is cancelled for which if the wave incident is not polarized obtains a reflected wave polarized orthogonally. The angle of Brewster is . For various angles r_// the is not cancelled but he is also always smaller regarding the r_^.

 

18) Dispersion of the light :

If a not monochromatic cancellation affects the interface to a not null angle, since the refractive index is function of the wavelength l , every harmonic member of the phantom comes rifratta to a various angle.

 

19) Polaroide :

It is an anisotropic material that is with various optical property to second of the direction in which the light propaga in they. The anisotrophy is due to asymmetry of the crystalline reticulum.

 

20) Law of Malus :

When a polarized light does not record on a polaroide, the outgoing intensity is half of the entering intensity, in how much the polaroide leaves to only pass the member of and parallel to its characteristic axis, if hour this cancellation then meets 2° polaroide an intensity that exits some is function of the angle formed from the characteristic aces of the 2 polaroidi.

Ha that is obtained to pact to calculate the intensity of the member parallel to the characteristic axis.

 

21) Light white woman :

The light white woman is not polarized given that the intensity that exits some from a polaroide is the half della entering intensity and not coherent in how much the sources emit trains of wave in accidental direction and with phase begins them accidental.

 

22) Wave with linear polarization :

It is sum of 2 waves with the same phase, one second polarized axis x and the other polarized the axis second y.

 

23) Wave with elliptic polarization:

Is sum of 2 waves sfasate of 90°, one second polarized axis x and lâaltra polarized the axis second y.

 

24) Wave with circular polarization :

It is a elliptic wave in which the two waves have the same module.

 

25) optical Filter :

Draft of a material that is transparent only for sure bands of frequencies, remaining comes absorbed.

 

26) Theorem of Kirchoff:

The value of and to the time t in external the P point to a surface containing sluice the source of the wave is expressed in terms of the value that and it had on the surface in a previous time.

From it the simplified version is extrapolated that is the principle of Huygens Fresnel.

 

27) Principle of Huygens - Fresnel :

It asserts that every point of the wave forehead can be thought like source of secondary spherical waves, whose envelope gives the forehead of wave to the time t'. The emitted secondary wave therefore is but only progressive, not regressive.

 

28) Interference between waves:

Interference between 2 waves is had when they have the same frequency and the same direction of propagation but sfasate between they. The intensity of the turning out wave is function of the phase-difference and is worth , as it is obtained squaring the sum of the electric fields of the 2 progressive waves.

 

29) coherent Waves :

2 waves are said coherent if they have the same frequency and sfasate between they of a constant factor. The phenomenon of the interference is not introduced for not coherent waves.

 

30) constructive and destructive Interference:

Analyzing  the;si it has destructive interference when the 2 waves sfasate of 180° in the which case the cosine are worth -1 and therefore the intensity of the turning out wave is much lowland, has instead constructive interference when the 2 waves are in phase for which the term of interference it is maximum.

 

31) optical Way :

The optical way of an luminous beam is given from the product of the refractive index for the length of the distance.

 

32) convergent Disc of a valve :

A convergent disc of a valve has the power to render flat a wave emitted from one spherical source mail in its fire and to make to converge on a point a wave emitted from one flat source.

 

33) Experiment of Young :

Parallel to the wave foreheads is sended to a flat wave against a diaphragm, in the diaphragm 2 cracks from which are dipanano spherical waves, the result is that on a screen they are come to produce of the frange of interference with a maximum centers them and the other maximums separates you of an angle being D the distance between the cracks.

 

34) Diffraction :

If we have a flat wave that affects a diaphragm in which a hole is practiced, on the screen not there is a clean separation between light and shadow but is had has of the frange of penumbra made from minimums and maximums.

 

35) Diffraction of Fraunhofer :

The wave incident on the diaphragm is a flat wave and the screen comes place to the infinite.

 

36) Diffraction of Fresnel :

The wave incident on the diaphragm is a flat wave and the screen comes place to the ended one.

 

37) Criterion of Rayleigh and separatory power :

The criterion of Rayleigh means to describe the phenomenon for which because of the diffraction, the image emitted from an object comes to increase itself, therefore if 2 are had objects separate to you from a sure angle, if such angle are smaller of that represents the distance between a maximum and a successive minimum, the 2 images get confused, the amount are said to be able separatory of the width crack d.

 

38) Problems connected to the double crack :

They are taken place is the interference that the diffraction, the outcome is obtained to leave from the interference figure modulating it with the diffraction figure.

 

39) Diffraction of Fraunhofer circular hole and its separatory power :

It is obtained ruotando around to the axis the figure of diffraction from rectangular crack, the separatory power is being d the diameter of the hole.

 

40) Reticulum of diffraction, resolutive power and sensibility :

Elevating of cracks is a reticulum constituted from a number much on which records the cancellation.

In short the result is much similar one to what we had already found for the double crack that is interference phenomena modulates to you from diffraction phenomena, in such a way obtains that the distance between 2 main maximums is being n the order of the maximum and D the distance between 2 cracks or step. The resolutive power del reticulum on the credit side order n is the minimal scostamento between 2 wavelengths that the reticulum succeeds to appreciate and is worth being n the order del maximum and N n° of cracks del the reticulum. The sensibility of the reticulum is instead the inverse one of the resolutive power of the same one.