# Formation of Image when light rays meet

1. Dec 21, 2013

### andyrk

1. The problem statement, all variables and given/known data
Why does an image form when light rays meet in ray optics? Is there explanation to it?

2. Relevant equations

3. The attempt at a solution
I thought of an explanation myself and thought that it cannot be explained just like many other things cannot be explained like universal law of gravitation (you cannot explain why two bodies attract each other)
But maybe if there does exist some explanation to it?

2. Dec 21, 2013

### tiny-tim

hi andyrk!

does it only form where they meet?

imagine you have a circle of differently coloured light bulbs

if you place a piece of paper either before or after where they meet, won't you still see a circle of differently coloured lights?

3. Dec 21, 2013

### haruspex

Suppose all the light rays originating at a point P on an object and heading off in some range of directions later meet and pass through another point X. Now suppose those same rays continue into your eye. Your eye cannot tell the difference between those rays and rays emanating from an object, like the original object, placed at X. If rays starting from other points near P also meet, at points somewhere near X, in a continuous mapping, then your eye will see a complete, though possibly distorted, object at X.