File:Diode laser.jpg

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Original file (3,060 × 2,036 pixels, file size: 1.05 MB, MIME type: image/jpeg)

Captions

Captions

Laser diode

Summary

[edit]
Description
English: Original caption: "This technology is known as a Tunable Diode Laser (TDL) gas sensor. The heart of the TDL system is a small laser diode (about 2mm square) that produces a narrow and specific wavelength of light tuned to a harmonic frequency of the water vapor molecule in the near infrared band. The light causes the molecule to vibrate and absorb the energy.

Once adjusted to the specific frequency of the molecule, the laser is minutely tuned to different wavelengths on either side of the target wavelength. By comparing the light energy being absorbed at the water vapor frequency, to the light energy at the surrounding frequencies, a very precise measurement can be made. Multiple measurements are made every second, making the system quick to respond to variations in the target gas.

TDL gas sensing technology is particularly good at detecting low levels of gases at the parts per million or even parts per billion level. With the vast majority of manufactured products relying more and more on gas measurement of some kind, commercial applications for this technique are broad. In every environment from wafer fabrication process control in the semiconductor industry to detecting trace levels of noxious gases in stack emissions, TDLs will be making news in the industrial and environmental monitoring sectors of the economy for years to come."
Date (Date from the IPTC metadata of the original TIFF version)
Source Jet Propulsion Laboratory website: http://technology.jpl.nasa.gov/gallery/index.cfm?page=imageDetail&ItemID=120&catId=8 (archive)
Author
This file is lacking author information.
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Common coin diameters for reference:

  • U.S. dollar (as of?):
    • 1¢: 19.05 mm, 0.75 in
    • 5¢: 21.21 mm, 0.84 in
    • 10¢: 17.91 mm, 0.71 in
    • 25¢: 24.26 mm, 0.94 in
    • 50¢: 30.61 mm, 1.22 in
    • $1: 26.5 mm, 1.02 in
  • Canadian dollar (as of?):
    • 1¢: 19.05 mm, 0.75 in
    • 5¢: 21.2 mm, 0.83 in
    • 10¢: 18.03 mm, 0.71 in
    • 25¢: 23.88 mm, 0.94 in
    • 50¢: 27.13 mm, 1.07 in
    • $1: 26.5 mm, 1.02 in
    • $2: 28 mm, 1.1 in
  • Pound sterling as of 2021:
    • 1p: 20.32 mm, 0.8 in
    • 2p: 25.91 mm, 1.02 in
    • 5p: 18 mm, 0.71 in
    • 10p: 24.5 mm, 0.96 in
    • 20p: 21.4 mm, 0.84 in
    • 50p: 27.3 mm, 1.07 in
    • £1: 23.03–23.43 mm, 0.91–0.92 in
    • £2: 28.4 mm, 1.12 in
  • Euro as of 2002:
    • 1c: 16.25 mm, 0.64 in
    • 2c: 18.75 mm, 0.74 in
    • 5c: 21.25 mm, 0.84 in
    • 10c: 19.75 mm, 0.78 in
    • 20c: 22.25 mm, 0.88 in
    • 50c: 24.25 mm, 0.95 in
    • €1: 23.25 mm, 0.92 in
    • €2: 25.75 mm, 1.01 in

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Licensing

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Public domain This file is in the public domain in the United States because it was solely created by NASA. NASA copyright policy states that "NASA material is not protected by copyright unless noted". (See Template:PD-USGov, NASA copyright policy page or JPL Image Use Policy.)
Warnings:

Original upload log

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The original description page was here. All following user names refer to en.wikipedia.
  • 2005-08-27 16:09 Deglr6328 3060×2036×8 (1096300 bytes) original caption: "This technology is known as a Tunable Diode Laser (TDL) gas sensor. The heart of the TDL system is a small laser diode (about 2mm square) that produces a narrow and specific wavelength of light tuned to a harmonic frequency of the water

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current02:47, 7 July 2007Thumbnail for version as of 02:47, 7 July 20073,060 × 2,036 (1.05 MB)Seedermaster~commonswiki (talk | contribs){{Information |Description=original caption: "This technology is known as a Tunable Diode Laser (TDL) gas sensor. The heart of the TDL system is a small laser diode (about 2mm square) that produces a narrow and specific wavelength of light tuned to a harm

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