Understanding Angular Spread: A Brief Explanation

[PhysicsKid0123]

Hi, I have a very simple question. What is meant by "angular spread"? I'm not too sure what is meant by that. I have tried looking on this forum as well as on google have not found any sort of definition or description. For example, the spread of light when diffracting? Or the spread of light between fringes?

 

[Doc Al]

You need to be more specific with the context of your question. Is there a problem or text that is prompting your question?

 

[sophiecentaur]

The actual definition is quite arbitrary and will depend upon the application (as mentioned above) but it is common to talk in terms of the 'half power' angles. This is the angle on either side of the peak power of the beam where the power density is one half of the peak power density. It is certainly the most common way to describe the beam width of a directional radio antenna (same situation at a much longer wavelength).

 

[insightful]

The simplest application has one base point (vertex) and two other points some distance from the base point. Drawing a line from the base point to each of the other points produces an angle. That angle is the "angular spread" between the two other points as seen from the base point. Get the point? ;-]

 

[sophiecentaur]

I would call that the angle subtended, it we're talking geometry.