Some powerful laser pointer can measure things seen only under a microscope or even perform delicate eye operations.Scientists did not purposely set out to invent the laser.Theodore Maiman developed the first working laser at Hughes Research Lab in 1960.In covering the evolution of laser science and technology, this article concentrates on two interacting series of developments, of laser devices and of laser applications.
In honor of the powerful laser pointer turning 50, here is a timeline of some of the more notable scientific accomplishments related to light amplification by stimulated emission of radiation (laser).It is considered the first use of the acronym laser.Theodore H. Maiman, a physicist at Hughes Research Laboratories in Malibu, Calif., constructs the first laser using a cylinder of synthetic ruby measuring 1 cm in diameter.An American Optical ruby laser is used to destroy a retinal tumor.
Although diode green laser pointer were a major breakthrough, all were wide-area h*mojunction devices.The most powerful continuously operating laser of its time, it is now used worldwide as a cutting tool in surgery and industry.Maiman and other laser pioneers found the laser advocacy group Laser Industry Association, which becomes the Laser Institute of America in 1972.So no one believed Gould later when he claimed he had come up with the idea for lasers on his own.
Gould included those possibilities in a laundry list of potential green laser pointer transitions in his patent application.Bell Labs reports the first yttrium aluminum garnet (YAG) laser.Stimulated emission is the basic principle of laser operation.Maiman's early laser used a powerful energy source to excite atoms in a synthetic ruby to higher energy levels.They had laser rods made from crystals of calcium fluoride doped with uranium, which they had earlier identified as a potential four-level laser system.
The first decade of Red Laser Pointer development also saw the emergence of a range of applications that shaped the design and marketing of laser products.Concern about the eye safety of laser beams used outdoors led to interest in lasers emitting at wavelengths beyond about 1.4mm.Military interest in laser weapons pushed developers to scale lasers to the highest possible powers.
Townes and Schawlow received patents for the basic Red Laser Pointer principle, and Maiman received a patent for the ruby laser.The procedure had to be re-engineered to use millisecond laser pulses.An effort by Spectra-Physics cofounder Earl Bell to improve helium-neon lasers led to development of ion lasers.The mid-1960s also saw the birth of chemical lasers, the family of gas lasers operating on IR transitions of molecules produced by chemical reactions.
Predecessor to the Laser Rifle Sight , the maser or 'microwave laser' was the first device to produce coherent electromagnetic waves.Not only a constant increase in the achievable output power qualifies a longterm-successful laser infrastructure, but also the constant improvement of not-so-obvious laser pulse parameters.The breakthrough demonstration earned headlines, but in the early years the laser was called "a solution looking for a problem."
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