When Arthur Schawlow and Charles Townes first described in 1959 how a laser might be made, many of Townes' friends teased him by asking if it would have any uses. Few scientists then could have imagined the myriad of applications to which the laser can be put. Now, of course, lasers are used for everything from transmitting telecommunication signals down optical fibres, monitoring atmospheric
... [Show full abstract] pollutants and measuring the ultra-fast vibrations of molecules to checking your groceries at the supermarket, fixing your eyesight and playing your favourite movie on DVD.
