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Blue laser
A blue laser emits electromagnetic radiation with a wavelength between 400 and 500 nanometers, which the human eye sees in the visible spectrum as blue or violet.
Blue lasers can be produced by:
Lasers emitting wavelengths below 445 nm appear violet, but are nonetheless also called blue lasers. Violet light's 405 nm short wavelength, on the visible spectrum, causes fluorescence in some chemicals, like radiation in the ultraviolet ("black light") spectrum (wavelengths less than 400 nm).
Prior to the 1960s and until the late 1990s, gas and argon-ion lasers were common and suffered from poor efficiencies (0.01%) and large sizes.
In the 1960s, advancements in sapphire creation allowed researchers to deposit GaN on a sapphire base to create blue lasers, but a lattice mismatch between the structures of gallium nitride and sapphire created many defects or dislocations, leading to short lifetimes (<10 hours) and low efficiency (<1%).
Additionally, gallium nitride (GaN) crystal layer construction proved difficult to manufacture as the material requires high nitrogen gas pressures and temperatures, similar to the environment for creating synthetic diamonds.
In 1992, Japanese inventor Shuji Nakamura, while working at Nichia Chemicals, invented the first blue semiconductor LED using an InGaN active region, GaN optical guide and AlGaN cladding, and four years later, the first low-power blue laser; eventually receiving the Millennium Technology Prize awarded in 2006, and a Nobel Prize for Physics along with Professor Isamu Akasaki, and Hiroshi Amano in 2014 for this invention. The gain medium defects still remained too high (106–1010 defects/cm2) resulting in a low-power laser with a short, < 300 hour lifetime using pulsed excitation.
In the late 1990s, Dr. Sylwester Porowski, at the Institute of High Pressure Physics at the Polish Academy of Sciences in Warsaw (Poland), developed technology to create gallium nitride mono-crystals with high structural quality using magnesium doping to create fewer than 100 defects/cm2 — at least 10,000 times better than prior attempts. In 1999, Nakamura used Polish-produced GaN crystals, creating lasers with twice the yield and ten times the lifetime of his original designs; 3,000 hours at 30 mW.
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Blue laser AI simulator
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Blue laser
A blue laser emits electromagnetic radiation with a wavelength between 400 and 500 nanometers, which the human eye sees in the visible spectrum as blue or violet.
Blue lasers can be produced by:
Lasers emitting wavelengths below 445 nm appear violet, but are nonetheless also called blue lasers. Violet light's 405 nm short wavelength, on the visible spectrum, causes fluorescence in some chemicals, like radiation in the ultraviolet ("black light") spectrum (wavelengths less than 400 nm).
Prior to the 1960s and until the late 1990s, gas and argon-ion lasers were common and suffered from poor efficiencies (0.01%) and large sizes.
In the 1960s, advancements in sapphire creation allowed researchers to deposit GaN on a sapphire base to create blue lasers, but a lattice mismatch between the structures of gallium nitride and sapphire created many defects or dislocations, leading to short lifetimes (<10 hours) and low efficiency (<1%).
Additionally, gallium nitride (GaN) crystal layer construction proved difficult to manufacture as the material requires high nitrogen gas pressures and temperatures, similar to the environment for creating synthetic diamonds.
In 1992, Japanese inventor Shuji Nakamura, while working at Nichia Chemicals, invented the first blue semiconductor LED using an InGaN active region, GaN optical guide and AlGaN cladding, and four years later, the first low-power blue laser; eventually receiving the Millennium Technology Prize awarded in 2006, and a Nobel Prize for Physics along with Professor Isamu Akasaki, and Hiroshi Amano in 2014 for this invention. The gain medium defects still remained too high (106–1010 defects/cm2) resulting in a low-power laser with a short, < 300 hour lifetime using pulsed excitation.
In the late 1990s, Dr. Sylwester Porowski, at the Institute of High Pressure Physics at the Polish Academy of Sciences in Warsaw (Poland), developed technology to create gallium nitride mono-crystals with high structural quality using magnesium doping to create fewer than 100 defects/cm2 — at least 10,000 times better than prior attempts. In 1999, Nakamura used Polish-produced GaN crystals, creating lasers with twice the yield and ten times the lifetime of his original designs; 3,000 hours at 30 mW.