Reflector VS Collimator

[MrNaz]

Aside from the obvious physical differences, what is the difference in application between these two types of optic? I am familiar with the use of both, but I can't really think of any situations where one would be definitely better than the other.

What are the main differences between them, and what are the considerations one would need to look at when deciding between the two?

 

[bshanahan14rulz]

I have an observation. collimators (by which I assume you mean the TIR optics) usually seem to make a more even circle of light while reflectors are better at making the spot surrounded by glow of direct illumination.

Now, I also have a question: why aren't collimators true collimators? they always have some kind of divergence, is this due to the light not being exactly from a point source, or more to do with the type of light emitted (as opposed to a laser diode)

 

[LumenHound]

I've played around with both over the last several years and have found that collimators have a slightly better overall light output when properly matched to the light source. The difference may not be obvious to the eye but my light meter tells me it's so.
Reflectors offer more versatility and are slightly more forgiving when you are trying to get perfect focus.

To each his own.