Click on the row with your desired specification to open link to products.

Features

• Absorptive Dye Encased in Hardened Polycarbonate Lenses (Resistant to Breaking)*
• Protection Lasts for a Minimum of 10 seconds at Maximum EN 207 Rated Exposure (See Specs Tutorial Tab)
• Specifications printed at the top of the lenses or on the frame
• Laser Glasses Available in Multiple Frame Styles
• Certificates of Conformity Available for Compliance with:
  • ANSI Z136.1 Standards for Safe Use of Lasers
  • ANSI Z87.1-2003 Standards for Occupational and Educational Personal Eye and Face Protection Devices
  • EN 207 Standards (Except LG14 Series, See Specs Tutorial Tab)
  • EN 208 Laser Alignment Standards (LG13, LG14, LG21, and LG22 Series Only, See Specs Tutorial Tab)

These Laser Safety Glasses provide CE certified laser radiation protection. The lenses of all glasses except for the LG11 series are made from absorptive dye encapsulated in hardened polycarbonate, which provides superior resistance to breakage and prevents minor scratches from affecting laser protection. The LG11(A) Laser Safety glasses use a Schott glass substrate.*

The optical density (OD) and LB-Rating for specific wavelength ranges are indelibly printed on the lens or frame for permanent identification without blocking the field of view^†. For a complete list of optical densities and LB-Ratings, please click on the row corresponding to each item # in the selection guide to the right.

Thorlabs offers laser safety glasses in up to four different frame styles (see the Frame Styles tab for details).

• The Universal style frame* can be worn over prescription glasses and features side and top shield protection from peripheral laser radiation.
• The Comfort style frame features detachable inserts for prescription lenses (please consult your doctor to fit lenses for the inserts) and an extended nose piece that may be more comfortable for users who have a low nose bridge.
• The Sport style frame is designed to wrap around the user's face, providing full laser protection with a continuous field of view.
• Finally, the Modern Goggle style comes with detachable inserts for prescription lenses and a built-in
  adjustable strap, making it the most secure of the frame styles. They have a gasket to create a seal around the customer’s eyes as well as vents to prevent fogging.

Each pair of laser safety glasses comes with a protective storage case, cleaning cloth, and adjustable neck strap. However, the Modern Goggle style does not come with the separate neck strap as the neckstrap for the Modern Goggles is built in.

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Modern Goggle style shown with built-in neck strap and detachable inserts for prescription lenses. Click on the image to show a front and rear view.

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Universal style glasses shown with included neck strap. This separate neck strap is included with Universal, Comfort, and Sport styles.

Care Instructions
When not being used, the laser safety glasses should be stored in their protective case and in an area where the temperature does not exceed 80 °F (26.6 °C). The cleaning cloth included with each pair of laser safety glasses can be used for removing dust from the surface of the lens. Products used for cleaning prescription eyeglasses are safe to use with our laser safety glasses. For disinfection of the glasses, we recommend mild detergent or soap and hot water or a dilution of isopropyl alcohol (up to 70% solution). We do not recommend any highly caustic solutions. The laser safety rating will not be affected by any of the above cleaning procedures.

Picking the Appropriate Laser Safety Glasses
Since the correct choice of laser safety eyewear depends upon many local factors that cannot be evaluated remotely, including the beam path, laser parameters, and lab environment, Thorlabs cannot recommend specific eyewear for your application. We would recommend discussing your needs with your organization's laser safety officer.

*The LG11 and LG11A are made using Schott glass, and therefore use a different frame design than our other Universal style laser glasses. Fit over prescription glasses may be affected (see the Frame Styles tab for details). To ensure CE compliance, only two styles are offered. OD and LB-Rating specifications for the LG11 and LG11A are printed on the frame.

†For maxmimum protection, our laser safety glasses should not be used more than five years from the production date. All of our laser safety glasses except for the LG11 and LG11A are inscribed with a production date code on the bottom-right corner of the right lens, as can be seen here. The date code is represented as a five-digit number, with the first two digits defining the year and the last three defining the day of the year. Thorlabs will not ship glasses with less than three years of usable life remaining.

OD to % Transmission Conversions

OD	Transmission	OD	Transmission
0.0	100%	5.0	0.001%
1.0	10%	6.0	0.0001%
2.0	1%	7.0	0.00001%
3.0	0.1%	8.0	0.000001%
4.0	0.01%	9.0	0.0000001%

OD = Optical Density
T = Transmission (decimal)

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Modern Goggle Style

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Sport Style

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Comfort Style

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Universal Style

LG1 Universal Style Laser Glasses on 1 x 1 cm Grid for Measuring Interior Dimensions

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Each pair of glasses and goggles comes with a protective carrying case, cleaning cloth, and adjustable neck strap (separate neck strap not included with Modern Goggles).

Universal Style
Universal Style laser safety glasses feature a large (145 mm x 53 mm) frame that can be worn comfortably on top of prescription glasses. They are equipped with lensed side shields and solid top shields to protect the user's eyes from laser radiation while maintaining peripheral vision. The frame has adjustable arm lengths to accommodate different temple sizes. Laser safety ratings are indelibly printed on the lenses to indicate the level of protection provided for specific wavelength ranges.

The LG11 is composed of a Schott Glass substrate, and uses a different frame than other universal style laser glasses that features side shields made from solid plastic providing full laser protection but at the expense of peripheral vision. These laser glasses may not fit over prescription glasses. Laser ratings on the LG11 are indelibly printed on the left side shield, not on the lenses.

Comfort Style
Comfort Style glasses feature a medium (145 mm x 47 mm) frame with solid side shields for full protection from peripheral laser radiation. While these laser safety glasses cannot be worn over prescription glasses, each pair includes a detachable insert for prescription lenses (seen by clicking on the the image to the right). Contact your doctor to fit lenses for the inserts. These frames are equipped with an extended nosepiece that allows the glasses to sit more comfortably on the noses of users who have a low nose bridge. Laser safety ratings are indelibly printed on the lenses (LG11A laser ratings are printed on the frame) to indicate the level of protection provided for specific wavelength ranges.

Sport Style
The Sport Style glasses have a compact (134 mm x 48 mm) frame designed for full laser safety coverage without the need for side shields and provide the user with a wide field of view. Glasses with this frame style have arms that feature adjustable lengths and an adjustable joint (seen by clicking on the image to the right) to customize the fit for different head shapes and sizes. These sport style glasses cannot be worn over prescription glasses and do not include inserts for prescription lenses. Laser safety ratings are indelibly printed on the lenses to indicate the level of protection provided for specific wavelength ranges.

Modern Goggle Style
The Modern Goggle Style features an adjustable strap, a gasket to create a seal around the eyes, as well as vents to prevent fogging. The interior dimensions of these laser goggles are
133 mm x 51 mm. The lenses have a diagonal length of 66 mm. Laser Safety Goggles are equipped with detachable inserts for prescription lenses (please consult your doctor to fit prescription lenses for the insert). Laser safety ratings are indelibly printed on the lenses to indicate the level of protection provided for specific wavelength ranges.

*** This guide is not intended as a substitute for reading and understanding the ANSI Z136 or EN 207 or EN 208 Laser Safety Standards. It is only meant to provide an introductory overview to understanding the markings on the lenses of the LG series of laser glasses. ***

ANSI Z136 and EN 207 Standards

Indelibly printed on the laser safety glasses are two sets of numbers: Optical Density (OD) and LB-Rating, which are both used to indicate the level of protection provided for specific wavelength ranges. The OD numbers indelibly printed on the laser safety glasses can be used to determine if the glasses meet the ANSI Z136 standards of laser safety protection for a given laser product. In addition, the OD can be used to calculate the transmission (T) of light through the laser safety glasses.

The European EN 207 standard for laser safety glasses requires that the protective eyewear be labeled with the CE mark and that the LB-Rating specifications are indelibly printed on the lens. In addition, the lenses and frames must be able to provide the stated level of protection for 10 seconds or 100 pulses depending on the mode of the laser. The LB-Rating is composed of 3 components: a wavelength range, a laser mode designation, and a scale number. The wavelength range engraved on the laser safety glasses is given in nm and is extremely important since the level of protection provided by the laser safety glasses is wavelength dependent. The laser mode designation is based on the duration of laser pulse emitted by the laser.

Laser Mode Designation

The scale number (LBn) is intended to be used in conjunction with the wavelength range and the laser mode designation in order to determine if the laser safety glasses meets the minimum required level of protection for a given laser; see the table below. If one component of the LB-Rating is shared, a plus sign is used to separate multiple wavelength ranges or laser modes and scale numbers in order to save space. In addition, a greater than, >, sign preceding a wavelength range indicates that the mode and scale number ratings for that wavelength range are valid for wavelengths of light greater than the bottom number in the range up to and including the top number in the range. For example, if the glasses were rated as 330-370 D LB2 and >370-500 D LB3 then at 370 nm the rating would be D LB2 and for all wavelengths greater than 370 nm up to and including 500 nm would be rated at D LB3.

There are two ways to use the table above: start with the scale number and calculate the maximum safe power density or start with a power density and calculate the minimum safe scale number. This is demonstrated by the two examples below.

Example 1: The LG3 laser safety glasses have an LB-Rating line that reads "180-315 D LB7 + IR LB4". So if the LG3 glasses are being used with a 10 µs pulsed 280 nm light source the table above can be referenced to find that, E=3x10ⁿ⁺¹ J/m², where in this example the scale number is LB4 so n=4. As a result, when the LG3 laser safety glasses are being used in this situation the maximum power density of the light source should not exceed 3x10⁵ J/m².

Example2: A CW Krypton Ion laser lasing at 647.1 nm has a maximum power density of 2.2x10⁴ W/m². Using the table above, the scale number can be calculated using LBn=log₁₀(P)-1, which results in a rounded up scale number of 4. The LG4 laser safety glasses meet the safety specifications of the European EN 207 standard for this example.

Alignment Rating (EN 208)

The LG13 and LG14 series of glasses are rated for laser alignment applications. This rating allows the lens to transmit a portion of the light for alignment purposes, while attenuating the light to eye-safe power levels in the event of accidental direct exposure to a beam. The rating is given as RB# where # is replaced by the minimum optical density at the specified wavelength or wavelength range (in nm). Along with this RB value is the maximum allowable power and energy of the laser over a Ø7 mm aperture. Power is given for pulses greater than 0.2 ms, while energy is specified for pulses from 1 ns to 0.2 ms. When using a pulsed laser, a correction factor of N1/4 must be multiplied by the maximum energy rating, replacing N with the number of pulses the laser produces in a 10 s interval.

Example: The LG14 laser safety glasses have an alignment rating of 1 W 2 x 10^-4 J 532 RB3. At 532 nm, the glasses will have an optical density between 3 and 4, correlating to transmission between 0.1% and 0.01%. The maximum power/energy over a Ø7 mm aperture that these glasses can be used with at 532 nm is 1 W for CW or pulses greater than 0.2 ms, and 2 x 10^-4 J for pulses from 1 ns to 0.2 ms.

Please refer to the official EN 208 standard that can be purchased from BSI.

P(mW) = Power in mW

Light Exiting a Fiber

When working with fiber optics, light emitted directly from the endface of a fiber is diverging. Thus, the power density is decreasing as the beam spreads and the danger of damage to the eye decreases. The table to the left lists the beam area created by light exiting a fiber for fibers with numerical apertures (NA) between 0.10 and 0.50. If you know the total power emitted from the fiber, you can calculate the power density at 25.4 mm (1") from the fiber tip. This power density will allow you to determine the safe fiber-tip viewing distances.

Laser Safety and Classification

Safe practices and proper usage of safety equipment should be taken into consideration when operating lasers. The eye is susceptible to injury, even from very low levels of laser light. Thorlabs offers a range of laser safety accessories that can be used to reduce the risk of accidents or injuries. Laser emission in the visible and near infrared spectral ranges has the greatest potential for retinal injury, as the cornea and lens are transparent to those wavelengths, and the lens can focus the laser energy onto the retina. 

Safe Practices and Light Safety Accessories

• Laser safety eyewear must be worn whenever working with Class 3 or 4 lasers.
• Regardless of laser class, Thorlabs recommends the use of laser safety eyewear whenever working with laser beams with non-negligible powers, since metallic tools such as screwdrivers can accidentally redirect a beam.
• Laser goggles designed for specific wavelengths should be clearly available near laser setups to protect the wearer from unintentional laser reflections.
• Goggles are marked with the wavelength range over which protection is afforded and the minimum optical density within that range.
• Laser Safety Curtains and Laser Safety Fabric shield other parts of the lab from high energy lasers.
• Blackout Materials can prevent direct or reflected light from leaving the experimental setup area.
• Thorlabs' Enclosure Systems can be used to contain optical setups to isolate or minimize laser hazards.
• A fiber-pigtailed laser should always be turned off before connecting it to or disconnecting it from another fiber, especially when the laser is at power levels above 10 mW.
• All beams should be terminated at the edge of the table, and laboratory doors should be closed whenever a laser is in use.
• Do not place laser beams at eye level.
• Carry out experiments on an optical table such that all laser beams travel horizontally.
• Remove unnecessary reflective items such as reflective jewelry (e.g., rings, watches, etc.) while working near the beam path.
• Be aware that lenses and other optical devices may reflect a portion of the incident beam from the front or rear surface.
• Operate a laser at the minimum power necessary for any operation.
• If possible, reduce the output power of a laser during alignment procedures.
• Use beam shutters and filters to reduce the beam power.
• Post appropriate warning signs or labels near laser setups or rooms.
• Use a laser sign with a lightbox if operating Class 3R or 4 lasers (i.e., lasers requiring the use of a safety interlock).
• Do not use Laser Viewing Cards in place of a proper Beam Trap.

Laser Classification

Lasers are categorized into different classes according to their ability to cause eye and other damage. The International Electrotechnical Commission (IEC) is a global organization that prepares and publishes international standards for all electrical, electronic, and related technologies. The IEC document 60825-1 outlines the safety of laser products. A description of each class of laser is given below:

Class	Description	Warning Label
1	This class of laser is safe under all conditions of normal use, including use with optical instruments for intrabeam viewing. Lasers in this class do not emit radiation at levels that may cause injury during normal operation, and therefore the maximum permissible exposure (MPE) cannot be exceeded. Class 1 lasers can also include enclosed, high-power lasers where exposure to the radiation is not possible without opening or shutting down the laser.
1M	Class 1M lasers are safe except when used in conjunction with optical components such as telescopes and microscopes. Lasers belonging to this class emit large-diameter or divergent beams, and the MPE cannot normally be exceeded unless focusing or imaging optics are used to narrow the beam. However, if the beam is refocused, the hazard may be increased and the class may be changed accordingly.
2	Class 2 lasers, which are limited to 1 mW of visible continuous-wave radiation, are safe because the blink reflex will limit the exposure in the eye to 0.25 seconds. This category only applies to visible radiation (400 - 700 nm).
2M	Because of the blink reflex, this class of laser is classified as safe as long as the beam is not viewed through optical instruments. This laser class also applies to larger-diameter or diverging laser beams.
3R	Class 3R lasers produce visible and invisible light that is hazardous under direct and specular-reflection viewing conditions. Eye injuries may occur if you directly view the beam, especially when using optical instruments. Lasers in this class are considered safe as long as they are handled with restricted beam viewing. The MPE can be exceeded with this class of laser; however, this presents a low risk level to injury. Visible, continuous-wave lasers in this class are limited to 5 mW of output power.
3B	Class 3B lasers are hazardous to the eye if exposed directly. Diffuse reflections are usually not harmful, but may be when using higher-power Class 3B lasers. Safe handling of devices in this class includes wearing protective eyewear where direct viewing of the laser beam may occur. Lasers of this class must be equipped with a key switch and a safety interlock; moreover, laser safety signs should be used, such that the laser cannot be used without the safety light turning on. Laser products with power output near the upper range of Class 3B may also cause skin burns.
4	This class of laser may cause damage to the skin, and also to the eye, even from the viewing of diffuse reflections. These hazards may also apply to indirect or non-specular reflections of the beam, even from apparently matte surfaces. Great care must be taken when handling these lasers. They also represent a fire risk, because they may ignite combustible material. Class 4 lasers must be equipped with a key switch and a safety interlock.
All class 2 lasers (and higher) must display, in addition to the corresponding sign above, this triangular warning sign.