I've noticed that the newest designs for traffic signals put the two green lights too close to each other.  If you're following a large truck, even by double the recommended following distance, you will not even see that there's a traffic light until you're in the intersection.

A few times I've been following a tractor trailer and not know that I entered an intersection under a red light.  You know truck drivers will take every last bit of a yellow to avoid stopping his rig. So the poor guy in the car behind him will enter the intersection on a red.   So far, knock on wood, no tickets. 

If someone does get a ticket in this situation, will the judge agree your vision of the light was obstructed even though you were following at a safe distance?

In this picture of NW 41 St and 107 Ave, looking west, notice that the two red lights are both over the center lane.  Why can't they be separated so that one is over the left and right lanes?  That way, each lane has a chance of seeing them.

I would like to see a 3 dimensional diagram showing the blind zone behind a a truck when the distance between the lights is less than the width of the truck. 

My recommendations:

Separate traffic lights by at least 150% the width of the center lane.

Install one light per lane, centered over the lane.   You may miss your lane's light behind a truck, but you stand a chance of seeing another lane's light.

Add lights on the vertical mast on the right side of the intersection as some cities do.