resonating chambers

[CPL.Luke]

what exactly makes a chamber resonate with a particular frequency? especially in relation to electromagnetic waves.

[swansont]

Being able to support a half-integral number of wavelengths, so the nodes occur at the boundaries, so there are no fields there to couple into the material to give you losses.

 

Generally a chamber can resonate at a large number of frequencies, so you add a lossy material at the ones you don't want, or I suppose you could change the shape slightly so that the other modes aren't supported.

[Locrian]

To repeat what swansont said, it's primarily the geometry. Then you must consider the material the sides of the cavity are made out of - are they solid? Are they covered with thin films? Also consider any material that fills the cavity.

[YT2095]

whether it`s EM, Sound or light etc... basicly think of a church bell or a piano string, make a noise at the correct frequency around either of these and they`ll resonate.

in effect their structure (materials, tension/stresses, geometry and so on) are "Tuned" to a particular frequency, upon receipt of an external influence of the same freq, certain areas of "pressure" build up, in the case of sound, it`s a physical distortion of the resonant material, this pressure is then released (it can`t self sustain without decay) creating a "ripple effect" and further pressure areas, at such a time that the external influence adds more power the original node of pressure gets reinforced again and so the Cycle continues.

in electronics it`s usualy using an Inductor and capacitor to create the "ringing" effect, for light I`m not 100% sure about, but i think it has to do with Mirrors of certain geometry and cavities.

Swansont will know more about that part.