Blue laser
A blue
Blue lasers can be produced by:
- direct, inorganic diode at 450 nm
- diode-pumped solid-state infrared lasers with frequency-doubling to 405nm
- upconversion of direct diode semiconductor lasers via thulium- or praseodymium-doped fibers at 480 nm[4]
- metal vapor, ionized gas lasers of helium-cadmium at 442 nm and 10–200 mW[5]
- argon-ion lasers at 458 and 488 nm[6]
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
History
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.[7]
In the 1960s, advancements in sapphire creation[8] 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
In the late 1990s, Dr.
In the 2000s, Japanese manufacturers mastered the production of a blue laser with 60 mW of power and long lifetimes, making them applicable for devices that read a dense (due to blue's short wavelength) high-speed stream of data from Blu-ray, BD-R, and BD-RE. Semiconductor lasers enabled the development of small, convenient and low-priced blue, violet, and ultraviolet (
Today, blue semiconductor lasers either use a sapphire substrate (primarily used by Nichia, which uses a contract manufacturer: Sony), or a GaN mono-crystal substrate (primarily used by TopGaN[16]); both covered with layers of gallium nitride. The GaN optical guide layer of the Nichia devices is formed from active region InGaN quantum wells or quantum dots spontaneously via self-assembly.
Polish technology is considered less expensive than the Japanese, but has a smaller share of the market. Another Polish company creates GaN crystals for use in blue diodes – Ammono,[17][18] but does not produce blue lasers.
Types
Direct Diode Semiconductor lasers
Blue, direct diode semiconductor lasers can be built using inorganic gallium nitride (GaN) or InGaN
Blue, direct diode lasers can also be fabricated with InGaN semiconductors (445 nm through 465 nm).[19] The InGaN devices are perceived as significantly brighter than GaN (405) nm direct diode lasers, since the longer wavelengths are closer to the peak sensitivity of the human eye.[20]
Use of phosphorescent direct diode blue organic light emitting diodes for lasers is impractical, due to poor lifetimes(<200hrs).[21]
Zener diodes can be incorporated into the circuitry to minimize ESD failures.[22]
Semiconductor lasers can be either driven by pulses or continuous wave operation.[23]
Edge or Vertical Cavity Surface Emitting
Semiconductor lasers may be configured to emit photons either perpendicular or horizontal to the lasing medium layers depending on end use.
Direct Diode-pumped solid state (DPSS), frequency doubled lasers
Direct diode infrared semiconductor lasers, readily available since the 1960s, typically as a pump source for telecom lasers, can be
Violet DPSS laser pointers (120 mW at 405 nm) use a direct diode infrared gallium arsenide (1 W @ 808 nm) lasers being directly doubled, without a longer-wave diode-pumped solid state laser interposed between diode laser and doubler-crystal results in higher-power.
Gas or Ion Lasers
Blue gas lasers are large and expensive instruments relying on population inversion in rare gas mixtures which use high currents and large cooling due to poor efficiency: 0.01%.[28] Blue beams can be produced using helium-cadmium gas lasers at 441.6 nm, or argon-ion lasers at 458 and 488 nm,
Blue Visual Appearance
The violet 405 nm laser (whether constructed directly from GaN or frequency-doubled GaAs laser diodes) is not in fact blue, but appears to the eye as violet, a color for which a human eye has a very limited sensitivity. When pointed at many white objects (such as white paper or white clothes which have been washed in certain washing powders) the visual appearance of the laser dot changes from violet to blue, due to fluorescence of brightening dyes.
For display applications which must appear "true blue", a wavelength of 445–450 nm is required. With advances in volume production, 445 nm
Applications
Areas of application of the blue laser include:
- High-definition Blu-rayplayers
- DLP and 3LCD projectors
- Telecommunications
- Information technology
- Optoelectronicdata storage at high density
- Environmental monitoring
- Electronic equipment
- Medical diagnostics
- Medical Procedures[31]
- Laryngology
- Phonosurgery
- Otology
- Rhinology
- Handheld projectors and displays
- Communication with submarines[32]
- Laser Projectors
- Laser Etchers and Cutters[33][34]
See also
- Blue LED
- List of laser articles
References
- ^ "The Blue Laser and Its Applications in Industry and Science". Opt Lasers. Retrieved 2023-06-23.
- ^ "GaN Nanowire Lasers" (PDF).
- ^ a b Kuchibhatla, Sridhar. "Master's Thesis GaN Blue based diodes".
- ^ Paschotta, Dr Rüdiger. "Blue lasers". www.rp-photonics.com. Retrieved 2023-06-24.
- ^ "StackPath". www.laserfocusworld.com. Retrieved 2023-06-24.
- ^ "StackPath". www.laserfocusworld.com. Retrieved 2023-06-24.
- ^ Paschotta, Dr Rüdiger. "Blue lasers". www.rp-photonics.com. Retrieved 2023-06-24.
- ^ "Sapphire Series Part 3: Modern Synthetic Sapphire Applications | Research & News". www.gia.eduhttps. Retrieved 2023-06-24.
- ^ NobelPrize.org Press Release (7 October 2014): The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2014 to Isamu Akasaki (Meijo University, Nagoya, Japan and Nagoya University, Japan), Hiroshi Amano (Nagoya University, Japan) and Shuji Nakamura (University of California, Santa Barbara, CA, USA) “for the invention of efficient blue light-emitting diodes which has enabled bright and energy-saving white light sources”
- ^ "Nobel Prize Press Release" (PDF).
- ^ "His Blue LEDs Changed How We Light Our World - IEEE Spectrum". spectrum.ieee.org. Retrieved 2023-06-24.
- ^ Shuji Nakamura wins the 2006 Millennium Technology Prize. Gizmag.com (2006-05-17). Retrieved on 2010-10-26.
- ^ Hogan, Melinda Rose and Hank. "A History of the Laser: 1960 - 2019". www.photonics.com. Retrieved 2023-06-24.
- ^ Paschotta, Dr Rüdiger. "Pulsed lasers". www.rp-photonics.com. Retrieved 2023-06-24.
- ISSN 1092-5783.
- ^ "TGL". topganlasers.com (in Polish). Retrieved 2023-06-24.
- ^ Stevenson, Richard. "The World's Best Gallium Nitride - IEEE Spectrum". spectrum.ieee.org. Retrieved 2023-06-24.
- ^ "Home". www.ammono.com. Retrieved 2023-06-24.
- ^ "Product Selector - ams-osram - ams". ams-osram. Retrieved 2023-06-24.
- ^ "Peak Sensitivity - an overview | ScienceDirect Topics". www.sciencedirect.com. Retrieved 2023-06-24.
- PMID 28561028.
- ^ "Nichia Laser Diode Spec Sheet" (PDF).
- ^ Paschotta, Dr Rüdiger. "Continuous-wave operation". www.rp-photonics.com. Retrieved 2023-06-24.
- ^ Paschotta, Dr Rüdiger. "Nonlinear crystal materials". www.rp-photonics.com. Retrieved 2023-06-24.
- ^ U. Eismann et al., Active and passive stabilization of a high power violet frequency-doubled diode laser, CLEO: Applications and Technology, pages JTu5A-65 (2016)
- ^ Lasers - Direct Diode vs Diode-Pumped Solid-State (DPSS), retrieved 2023-06-24
- ^ "The Blue Laser and Its Applications in Industry and Science". Opt Lasers. Retrieved 2023-06-24.
- ^ Paschotta, Dr Rüdiger. "Blue lasers". www.rp-photonics.com. Retrieved 2023-06-24.
- ^ "What's the difference between laser phosphor and RGB laser?". www.barco.com. Retrieved 2023-06-24.
- ^ "Lasers and Dyes for Multicolor Flow Cytometry". www.bdbiosciences.com. Retrieved 2023-06-24.
- ^ "WOLF Diode Laser CO2 Laser - Blue Laser ENT". www.arclaser.com. Retrieved 2023-06-23.
- ^ "Defense Advanced Research Projects Agency Strategic Plan" (PDF). May 2009. p. 18. Archived (PDF) from the original on January 21, 2022. Retrieved 2021-10-25.
- ^ "The Blue Laser and Its Applications in Industry and Science". Opt Lasers. Retrieved 2023-06-24.
- ^ "Kilowatt class Lasers".