prism sights and red dot sights

[sig220mwxxxx]

I am about to purchase a sight for a tactical carbine. I am seeing both red dot sights and prism red dot sights. What is the difference between the two? I am 62 years old and am not sure if it would make a difference to me but would like to know.

 

[g.willikers]

Opticsplanet.com usually has good info on just about everything concerning optics.