Green VS Red

Green Laser Pointers vs. Red Laser Pointers

Many years ago, laser pointers were a very expensive luxury that only a few folks could afford.  Even when they could afford them they were rather hard to find and had lots of other issues like being oversized and eating batteries. But as time went on the production of red laser LEDs dropped dramtically and soon laser pointers were priced at the level where they could be even bought just for teasing and playing with the cat.

About the time that red laser pointers became very affordable, the first green laser pointers appeared on the market. Like the first (red) laser pointers these were very expensive. The average price for a bulky green pointer was about $500. But like many other things in the electronics market the price started to drop as production costs fell. These days it it not unreasonable to find a green laser pointer for less than $100.

But why would one want a green laser pointer when red ones can be had for under $10? The answer is simple: The human eye is much more sensitive to green light, especially under daylight conditions, where our eyes are as much as 10 times as sensitive to green light as they are to red. If one is using a red laser pointer in a brightly lit lecture hall, it might well be hard to see by people attending the lecture. But use a green laser pointer and even folks sitting in the back will be able to see where you are pointing. Yet both the green laser and red laser will be putting out the same amount of power.

We made a short video to demonstrate this effect: