Brewster's angle and the intensity of reflected light

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Discussion Overview

The discussion revolves around Brewster's angle and its implications for the intensity of reflected and refracted light. Participants explore the behavior of light with different electric field orientations at this specific angle, addressing both theoretical and conceptual aspects.

Discussion Character

  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant suggests that at Brewster's angle, all incident light with its electric field parallel to the plane of incidence is refracted, while the light with its electric field perpendicular is reflected, proposing a specific intensity distribution.
  • Another participant corrects the initial claim, stating that some of the light with an electric field perpendicular to the plane of incidence will also be refracted, indicating that not all of it is reflected.
  • A later reply emphasizes that under ideal conditions, the proportions of reflected and refracted light can be calculated using the Fresnel Equations, suggesting a more nuanced understanding of the light's behavior.
  • One participant rephrases the earlier claim, stating that while all parallel light is refracted, the reflected light is exclusively perpendicular, and notes that the refracted light includes both types but minimizes the perpendicular component at Brewster's angle.

Areas of Agreement / Disagreement

Participants express disagreement regarding the behavior of light at Brewster's angle, particularly about the proportions of reflected and refracted light. No consensus is reached on the exact nature of the light's behavior.

Contextual Notes

Limitations include assumptions about ideal conditions and the dependence on the Fresnel Equations for accurate calculations of light intensity distribution.

PainterGuy
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Hi,

Would it be correct to say that at Brewster's angle, all the incident light which has its electric field parallel to the plane of incidence gets refracted, and the rest of light whose electric field is perpendicular to the plane of incidence gets reflected? For example, if the light whose electric field is parallel to the plane of incidence contributes 70% towards the intensity of light then at Brewster angle, the reflected light has intensity of only 30%. Could you please help me with it?
 
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The "all the incident light which has its electric field parallel to the plane of incidence gets refracted" is correct.
The "and the rest of light whose electric field is perpendicular to the plane of incidence gets reflected" is not correct.

Some of the light with an electric field perpendicular to the plane of incidence will also be refracted.

In the example you gave:
The 70% that is parallel will be fully refracted.
The 30% that is perpendicular will be split - with most of it being reflected.
 
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.Scott said:
The "and the rest of light whose electric field is perpendicular to the plane of incidence gets reflected" is not correct.

Thank you!

Wouldn't it be correct in an ideal case?
 
No.
Under "ideal" conditions, the proportion of light reflected and refracted can be computer by using the Fresnel Equations.
 
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Thank you.

I think that it could be rephrased as follows.

At Brewster's angle, all the incident light which has its electric field parallel to the plane of incidence gets refracted, and all the reflected light has its electric field perpendicular to the plane of incidence. The refracted light would consist of both 'types' of light, but at Brewster's angle the portion of light whose electric field is perpendicular to the plane of incidence is at its minimum in the total of refracted light.
 
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