why are commercially available lasers almost always red?


why are commercially available lasers almost always red?

In: Technology

Because they’re cheap and easy to make.

Take blue lasers for example. These were only invented in the mid 1990’s and it took another decade before there were commercially viable uses for them (eg Blu Ray).

You *can* buy them, you just need to go looking for it and expect to pay more.

Red light is a low energy radiation that uses less battery. Green, blue, etc are higher energy radiations that use up your battery faster. Lasers can be any if these colors but the red one is the most practical because it will last longer before having to replace a battery.

Many times a red gas laser will be a helium neon laser. The frequency cannot be easily altered because of atomic properties , so we have to deal with it.

Another used color is green at 532 nm, which is always a Nd YAG laser which operates at 1064 nm which you cannot see but it goes through a frequency doubler so it becomes the classic green color.