What Do Optical Density and Wavelength Mean?

When shopping for laser glasses, know the terminology, and you’ll have a good idea of what the protection rating on your glasses really means.

What Do Optical Density and Wavelength Mean?

Wavelength and Optical DensityOptical density and wavelength work together in laser protection to indicate the amount of protection you get from a given laser. While many facilities have a Laser Safety Officer (LSO) to help decide which laser glasses are appropriate for a laser, many don’t.

If you are curious about what optical density and wavelength mean, this will give you a good idea:

  • Wavelength is the length of a wave from a given point on the wave to the next time that point repeats. In other words, if you’re looking at waves in the ocean, the wavelength can be measured from crest to crest; it’s the distance between repetitions of the shape of the wave. In laser safety, wavelength corresponds to the light (visible or invisible) that is emitted from the laser.
  • Wavelength corresponds inversely with frequency. The narrower the wavelength, the faster that wave will repeat itself (since these waves are all traveling at the same speed, the speed of light). So, to go back to the ocean analogy, the closer the waves are together, the shorter the wavelength is, and the more frequently they will crash against the shore. When the waves are spaced far apart (longer wavelength), they crash less frequently against the shore, assuming that all the waves are traveling at the same speed.
  • Optical density, or OD, is a logarithmic function that corresponds to the amount of light that a lens transmits at a specific wavelength. OD is specified for specific wavelengths or ranges of wavelengths.
  • Transmittance, or the amount of light that passes through a lens, is a decimal fraction of the total light you started with. So if a lens transmits 0.01% of the light at a specified wavelength, its decimal fraction transmittance, or T, would be 0.00001.
  • The equation that relates optical density to transmittance is: OD=log(1/T). The logarithm is base 10.
  • An example of optical density would be: if you have an OD of 5, your transmittance is 0.00001, or 0.01%. 5=log(1/0.00001).

This can get a bit complicated if you are not familiar with log functions, but the main thing to notice is that, as OD goes up, Transmittance goes down. So, the higher your OD at a given wavelength (or range of wavelengths), the less light will pass through at that wavelength. This goes for visible and invisible light.

Shop Laser Safety Goggles

The important things to consider are the class of your laser, its operating wavelength, and what amount of light is safe to pass through your lens. Once you figure that out, it’s a simple matter of figuring out the OD you need at the laser’s operating wavelength, and you can shop for your lenses accordingly. Shop wisely for your laser safety goggles, and stay safe!

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What Do Optical Density and Wavelength Mean?

When shopping for laser glasses, know the terminology, and you’ll have a good idea of what the protection rating on your glasses really means.

What Do Optical Density and Wavelength Mean?

Wavelength and Optical DensityOptical density and wavelength work together in laser protection to indicate the amount of protection you get from a given laser. While many facilities have a Laser Safety Officer (LSO) to help decide which laser glasses are appropriate for a laser, many don’t.

If you are curious about what optical density and wavelength mean, this will give you a good idea:

  • Wavelength is the length of a wave from a given point on the wave to the next time that point repeats. In other words, if you’re looking at waves in the ocean, the wavelength can be measured from crest to crest; it’s the distance between repetitions of the shape of the wave. In laser safety, wavelength corresponds to the light (visible or invisible) that is emitted from the laser.
  • Wavelength corresponds inversely with frequency. The narrower the wavelength, the faster that wave will repeat itself (since these waves are all traveling at the same speed, the speed of light). So, to go back to the ocean analogy, the closer the waves are together, the shorter the wavelength is, and the more frequently they will crash against the shore. When the waves are spaced far apart (longer wavelength), they crash less frequently against the shore, assuming that all the waves are traveling at the same speed.
  • Optical density, or OD, is a logarithmic function that corresponds to the amount of light that a lens transmits at a specific wavelength. OD is specified for specific wavelengths or ranges of wavelengths.
  • Transmittance, or the amount of light that passes through a lens, is a decimal fraction of the total light you started with. So if a lens transmits 0.01% of the light at a specified wavelength, its decimal fraction transmittance, or T, would be 0.00001.
  • The equation that relates optical density to transmittance is: OD=log(1/T). The logarithm is base 10.
  • An example of optical density would be: if you have an OD of 5, your transmittance is 0.00001, or 0.01%. 5=log(1/0.00001).

This can get a bit complicated if you are not familiar with log functions, but the main thing to notice is that, as OD goes up, Transmittance goes down. So, the higher your OD at a given wavelength (or range of wavelengths), the less light will pass through at that wavelength. This goes for visible and invisible light.

Shop Laser Safety Goggles

The important things to consider are the class of your laser, its operating wavelength, and what amount of light is safe to pass through your lens. Once you figure that out, it’s a simple matter of figuring out the OD you need at the laser’s operating wavelength, and you can shop for your lenses accordingly. Shop wisely for your laser safety goggles, and stay safe!

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What Do Optical Density and Wavelength Mean?

When shopping for laser glasses, know the terminology, and you’ll have a good idea of what the protection rating on your glasses really means.

What Do Optical Density and Wavelength Mean?

Wavelength and Optical DensityOptical density and wavelength work together in laser protection to indicate the amount of protection you get from a given laser. While many facilities have a Laser Safety Officer (LSO) to help decide which laser glasses are appropriate for a laser, many don’t.

If you are curious about what optical density and wavelength mean, this will give you a good idea:

  • Wavelength is the length of a wave from a given point on the wave to the next time that point repeats. In other words, if you’re looking at waves in the ocean, the wavelength can be measured from crest to crest; it’s the distance between repetitions of the shape of the wave. In laser safety, wavelength corresponds to the light (visible or invisible) that is emitted from the laser.
  • Wavelength corresponds inversely with frequency. The narrower the wavelength, the faster that wave will repeat itself (since these waves are all traveling at the same speed, the speed of light). So, to go back to the ocean analogy, the closer the waves are together, the shorter the wavelength is, and the more frequently they will crash against the shore. When the waves are spaced far apart (longer wavelength), they crash less frequently against the shore, assuming that all the waves are traveling at the same speed.
  • Optical density, or OD, is a logarithmic function that corresponds to the amount of light that a lens transmits at a specific wavelength. OD is specified for specific wavelengths or ranges of wavelengths.
  • Transmittance, or the amount of light that passes through a lens, is a decimal fraction of the total light you started with. So if a lens transmits 0.01% of the light at a specified wavelength, its decimal fraction transmittance, or T, would be 0.00001.
  • The equation that relates optical density to transmittance is: OD=log(1/T). The logarithm is base 10.
  • An example of optical density would be: if you have an OD of 5, your transmittance is 0.00001, or 0.01%. 5=log(1/0.00001).

This can get a bit complicated if you are not familiar with log functions, but the main thing to notice is that, as OD goes up, Transmittance goes down. So, the higher your OD at a given wavelength (or range of wavelengths), the less light will pass through at that wavelength. This goes for visible and invisible light.

Shop Laser Safety Goggles

The important things to consider are the class of your laser, its operating wavelength, and what amount of light is safe to pass through your lens. Once you figure that out, it’s a simple matter of figuring out the OD you need at the laser’s operating wavelength, and you can shop for your lenses accordingly. Shop wisely for your laser safety goggles, and stay safe!

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Trackback URL http://lasersafetygoggles.com/what-do-optical-density-and-wavelength-mean/trackback/

What Do Optical Density and Wavelength Mean?

When shopping for laser glasses, know the terminology, and you’ll have a good idea of what the protection rating on your glasses really means.

What Do Optical Density and Wavelength Mean?

Wavelength and Optical DensityOptical density and wavelength work together in laser protection to indicate the amount of protection you get from a given laser. While many facilities have a Laser Safety Officer (LSO) to help decide which laser glasses are appropriate for a laser, many don’t.

If you are curious about what optical density and wavelength mean, this will give you a good idea:

  • Wavelength is the length of a wave from a given point on the wave to the next time that point repeats. In other words, if you’re looking at waves in the ocean, the wavelength can be measured from crest to crest; it’s the distance between repetitions of the shape of the wave. In laser safety, wavelength corresponds to the light (visible or invisible) that is emitted from the laser.
  • Wavelength corresponds inversely with frequency. The narrower the wavelength, the faster that wave will repeat itself (since these waves are all traveling at the same speed, the speed of light). So, to go back to the ocean analogy, the closer the waves are together, the shorter the wavelength is, and the more frequently they will crash against the shore. When the waves are spaced far apart (longer wavelength), they crash less frequently against the shore, assuming that all the waves are traveling at the same speed.
  • Optical density, or OD, is a logarithmic function that corresponds to the amount of light that a lens transmits at a specific wavelength. OD is specified for specific wavelengths or ranges of wavelengths.
  • Transmittance, or the amount of light that passes through a lens, is a decimal fraction of the total light you started with. So if a lens transmits 0.01% of the light at a specified wavelength, its decimal fraction transmittance, or T, would be 0.00001.
  • The equation that relates optical density to transmittance is: OD=log(1/T). The logarithm is base 10.
  • An example of optical density would be: if you have an OD of 5, your transmittance is 0.00001, or 0.01%. 5=log(1/0.00001).

This can get a bit complicated if you are not familiar with log functions, but the main thing to notice is that, as OD goes up, Transmittance goes down. So, the higher your OD at a given wavelength (or range of wavelengths), the less light will pass through at that wavelength. This goes for visible and invisible light.

Shop Laser Safety Goggles

The important things to consider are the class of your laser, its operating wavelength, and what amount of light is safe to pass through your lens. Once you figure that out, it’s a simple matter of figuring out the OD you need at the laser’s operating wavelength, and you can shop for your lenses accordingly. Shop wisely for your laser safety goggles, and stay safe!

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