Laser

                                   In my opinion, the laser technology comes from focusing photons of lights on a single spot and such approach makes it more powerful than a beam of light. In addition, I heard many times that it is dangerous to point out a laser dot in someone’s eye.
                                   Furthermore, as we learned about LEDs and that recently blue LED got invented, now that I think about it, I assume I have never seen a blue laser, although I’ve seen red laser and in few cases green laser. Therefore, I assume lasers and LEDs must have a very similar structure for that reason. additional question: why blue laser was the last one to be invented, if it got invented, and is it similar to LED concept and reason? I also assume practically it is harder to create green laser comparing to red ones, since, red light laser devices are much more and cheaper comparing to green ones.

   Applications;;

Laser technology must have a various application fields, in almost any of the science field you may observe laser technology applications and devices. In the following I mention the applications of such technology as far as I encountered, observed, used, or read about:
Computer devices such as laser mouse, laser presentation, CD ROMs and DVD ROMs
Astronomy and communication applications
Medicine, surgery, and health
War machines, guns and tanks
Cutting matters in metallurgy industry and related industries
Robotics, especially in image processing and calculating distances
Toys