For example, if I take 2 laser pointers and arrange them in such a way that their beams cross each other (forming a kind of "x") will the resultant colour at the point at which they intersect be of a very high intensity? E.g. take 2 laser pointers, of which one produces blue light and another red, but the beams of light are barely visible. Where the two beams intersect, will the brown colour be of higher intensity? (If you didn't know: blue+red=brown.)
Laser pointers use diodes (that's why I used the tag).