Intensity and frequence of light

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Discussion Overview

The discussion centers around the relationship between the intensity and frequency of light, specifically whether it is possible to increase the intensity of light without changing its amplitude by increasing its frequency. The scope includes theoretical considerations and technical aspects related to optics and electromagnetic radiation.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • Some participants question whether intensity can be increased by changing frequency, suggesting that frequency determines the type of electromagnetic radiation and does not directly imply changes in intensity.
  • One participant notes that increasing frequency beyond visible light leads to invisible radiation, such as ultraviolet light and x-rays.
  • Another participant discusses the concept of non-linear optics, mentioning that high intensity can modify materials like glass and lead to effects such as temporary lensing or cracking.
  • A later reply emphasizes the distinction between thermal effects and true non-linear effects, arguing that true non-linear effects depend solely on intensity and occur rapidly, unlike thermal effects which are slower.

Areas of Agreement / Disagreement

Participants express differing views on the relationship between intensity and frequency, with no consensus reached on whether intensity can be increased by changing frequency without altering amplitude.

Contextual Notes

Participants highlight the importance of distinguishing between different types of effects (thermal vs. non-linear) and the implications of frequency changes on the nature of light.

yashpurohit
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I have a doubt that can we increase the intensity of light without changing its amplitude and by increasing its frequency ? :what:
 
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If you increase the frequency of light past a certain value, it becomes invisible to the human eye (for example, ultraviolet light, x-rays, and gamma rays are names for progressively higher frequency EM radiation.)
 
yashpurohit said:
I have a doubt that can we increase the intensity of light without changing its amplitude and by increasing its frequency ? :what:

Frequency cannot imply intensity. Frequency decides the nature of EM radiation, so as Steamking said, increasing frequency will yield you a different kind of wave. In the visible region itself, changes in frequency will change the 'colour' of visible light, not it's intensity.
 
yashpurohit said:
I have a doubt that can we increase the intensity of light without changing its amplitude and by increasing its frequency ? :what:

As the intensity of light increases you enter the realm of non-linear optics, which is studied with high power lasers. For example, when you shine ordinary light on a flat piece of glass it simply passes through - a small bit is absorbed, some is reflected, and the rest is transmitted.

But as the intensity increases, the absorbed light can modify the glass slightly - through heating - and the glass may temporarily act as a lens, further focusing the light. This further increase in intensity may actually crack the glass.

This is easy to due in a high powered laser lab; I've seen it done several times.

With the appropriate crystals (birefringent) it is also possible to change the frequency of light. This was first done in 1962. This technique is used all of the time, and is how they make green laser pointers: https://en.wikipedia.org/wiki/Laser_pointer#Green
 
UltrafastPED said:
But as the intensity increases, the absorbed light can modify the glass slightly - through heating - and the glass may temporarily act as a lens, further focusing the light. This further increase in intensity may actually crack the glass.

Sorry to nitpik, but this is just a thermo-optic effect, not a true nonlinear effect.

True nonlinear effects (e.g. the Kerr effect) depend on intensity only, not temperature. This distinction is important as thermal effects are slow, whereas true nonlinear effects are very fast.

Claude.
 

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