Does Coherent Light Waves Frequency Matter?

AI Thread Summary
Coherent light waves must have a constant phase difference, which typically implies they share the same frequency. However, light waves with the same frequency can still be incoherent if they lack a consistent phase relationship. Coherence is defined by two main factors: temporal coherence, which relates to frequency spread, and spatial coherence, which pertains to the source's size. For instance, lasers often produce temporally coherent but spatially incoherent light, while distant stars can emit spatially coherent yet temporally incoherent radiation. Understanding these distinctions is crucial for applications in optics and photonics.
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does coherent LIGHT waves with a constant phase difference MUST have the same frequency?

what about LIGHT waves with the same frequency only? will it be not coherent??
 
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Coherence is a statistical measure of the field. The two major 'limits' are temporal coherence, related to frequency spread, and spatial coherence, related to the size of the source. So, it's very possible to have a highly temporally coherent, spatially incoherent source (most lasers have this type of radiation), or highly spatially coherent and tempoerally incoherent radiation (distant stars).
 
err so may i know what you are trying to say? i can't catch your words...maybe a direct answer to those questions would be better

TQ
 
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