1、 Standard positioning and scope of application
EN207 is a mandatory standard for laser radiation protective goggles in the European Union, officially known as "Personal Eye Protection Equipment -
Laser Radiation Protective Filters and Goggles". Laser protective goggles sold in the EU market must pass this standard test and be affixed with the
CE mark. Manufacturers are not allowed to self certify and must be tested and certified by independent institutions recognized by the government.
2、 Classification of laser working modes
EN207 first divides lasers into four categories based on their pulse width, with different modes corresponding to different testing conditions:
D mode (continuous wave CW): pulse width ≥ 0.25 seconds, the lens needs to withstand at least 10 seconds of direct laser irradiation during testing
I-mode (pulsed laser): The pulse width is between 1 microsecond and 0.25 seconds, and the test requires withstanding 100 pulses
R mode (giant pulse/Q switch): pulse width between 1 nanosecond and 1 microsecond, testing requires withstanding 100 pulses
M-mode (mode locking/ultra short pulse): pulse width<1 nanosecond (picosecond, femtosecond level), testing requires withstanding 100 pulses
3、 Protection level (L/LB level)
The protection level consists of three parts: wavelength range+laser mode code+proportional number (scale number).
Wavelength range: indicate the starting and ending wavelengths of protection, in nanometers (nm)
Laser mode code: one of D, I, R, M
Proportional number (Ln): from L1 to L10, the larger the number, the stronger the protective ability, representing the lower limit of optical density
For example, the label "900-1100 D LB6" indicates that in the wavelength range of 900-1100 nm, the protection level for continuous wave lasers is
LB6, corresponding to an optical density not lower than OD6, and the lens and frame can withstand a power density of 100 MW/m ² in a 10 second
direct irradiation test.
4、 Core testing projects
Optical Density (OD) Test
Measure the light attenuation ability of a lens at a specific wavelength. The relationship between OD value and transmittance is: OD=- log ₁₀ (T). For
example, OD6 means attenuating the laser intensity to one millionth (10 ⁻⁶) of its original level.
Laser radiation stability test (damage threshold test)
This is the key difference between EN207 and other standards. Both lenses and frames must undergo direct laser irradiation testing:
Continuous wave laser: direct irradiation for at least 5 seconds (some mechanisms test for 10 seconds)
Pulse laser: 100 pulses
After testing, the lens must not burn through, must not produce fragments or cracks on the inner side (facing the eyes), and the protective performance
must not fail.
Mechanical performance testing
Including impact resistance, scratch resistance, high temperature resistance, structural strength, etc., to ensure that the protective performance of the
mirror does not decrease during long-term use.
Optical performance testing
Evaluate indicators such as transmittance, light scattering, imaging quality, color difference, and imaging distortion to ensure that the wearer's field of
view is clear and does not affect normal operation.
Identification requirements
Protective goggles that have passed EN207 testing must be permanently and clearly labeled on the lens:
Protection wavelength range
Laser mode code (D/I/R/M)
LB level number
CE mark
If the lens grade is marked in segments according to wavelength, it needs to be confirmed in segments based on its own usage conditions. For example,
the label "530-570 D L5+>570-700 D L6" indicates a level of D L5 at 570 nm, and a level of D L6 for wavelengths greater than 570 nm and less than or
equal to 700 nm.
5、 Relationship with optical density (OD)
EN207 does not only look at OD values. Optical density only reflects attenuation ability, while EN207 also requires the material itself to withstand the
power/energy density of direct laser irradiation. Even if the OD value is high enough, if the filter material burns through, cracks, or melts under direct
laser irradiation, it still does not meet EN207 requirements. Therefore, when choosing protective goggles, LB level takes priority over OD value.
6、 Certification Process Overview
Product classification and standard determination: Determine the applicable EN207 clauses based on the intended use
Sample preparation: Provide representative samples
Laboratory testing: optical performance, laser protection performance, mechanical performance, etc
Technical document review: including design drawings, material lists, test reports, risk assessment reports, etc., must be kept for at least 10 years
Sign the conformity declaration and affix the CE mark
Contact phone number: 19925421523
