Laser classes -also referred to as laser safety classes are essential for assessing the eye safety of laser modules. At Z-LASER, laser modules undergoe a rigorous, standard-compliant test procedure to meet the requirements of DIN EN 60825-1. The test setup simulates the human eye under the most sensitive conditions: in complete darkness with a fully dilated pupil. This article provides an overview of the test setup, measurement procedure and labelling used for laser classification at Z-LASER.
Why Is Laser Classification Required?
Laser classification provides the basis for assessing eye safety and for defining the appropriate protective measures when laser modules are used. After classification, each laser module receives a warning label indicating the laser class.
Basic for Laser Classification: DIN EN 60825-1
The internationally applicable standard DIN EN 60825-1 defines how laser classification must be carried out. It specifies requirements and measurement conditions and provides a standardised, traceable basis for assigning laser classes. For example, the standard defines the measurement distance, which apertures and lenses may be used, and how the test procedure is structured. This ensures laser classification follows a uniform and verifiable process.
The Test Setup: Simulating the Human Eye
Laser classes are determined under so-called restrictive conditions. In other words, the test setup reproduces the human eye in a worst case scenario: complete darkness with a fully dilated pupil. This ensures laser classification is performed under defined, standard compliant measurement conditions.
A standardised 7 mm aperture is positioned in front of the measuring head. This corresponds to the maximum opening of the human pupil in complete darkness. A downstream collimator lens then reproduces the eye’s optics in the measurement setup and establishes the standard compliant measurement situation. The laser radiation is limited by the 7 mm aperture.
Measurement Along the Entire Laser Line
Using a multi-axis positioning unit, the measuring head is moved systematically along the projected laser line so that every section of the line is measured. This identifies the most restrictive case, namely the critical point, i.e., the point with the highest measured value (maximum value) along the laser line. This maximum value is decisive and forms the basis for assigning a laser class.
Specialized software evaluates the maximum value (most restrictive case) and assigns the laser module to the appropriate laser class based on the limit values defined in DIN EN 60825-1. The results are documented so that classification and labelling can be clearly derived. In addition, the software has been customized at Z-LASER to display the limit values for the adjacent laser classes.
Conclusion: Transparent, Standard-Compliant Laser Classification in Accordance with DIN EN 60825-1
Through the rigorous, standard-compliant test and classification procedure, the laser classes of Z-LASER laser modules are determined and documented in a standardised way in accordance with DIN EN 60825-1, meeting the requirements for laser classification and product labelling. The test setup reproduces the human eye in the worst case. The measurement identifies the most restrictive case along the laser line, and the software performs the standard-compliant evaluation for laser class assignment. This provides users with a reliable basis for safety assessment and risk assessment, particularly regarding eye safety and the protective measures required.
Do you have questions about laser classes or standard compliant laser classification? Contact Z-LASER. Our experts are happy to support you without obligation.
Frequently Asked Questions
Laser classes (or laser safety classes) categorize lasers and laser modules according to the potential hazard to the human eye. The scale ranges from Class 1 (safe under intended use) to Class 4 (high hazard, requires strict protective measures).
The 7 mm aperture simulates the fully dilated pupil of the human eye in complete darkness, representing a worst-case scenario. This captures the maximum possible light entry that could reach the eye under these conditions.
For assessing the potential hazard to the eye, it is not an average value that matters but the highest measured value along the laser line (critical point). At this value, the eye could potentially be harmed even under short exposure. For this reason, the highest measured value is used for laser classification and for assigning the correct laser class.
Yes. Z-LASER lasers undergo an internal testing and classification process in accordance with DIN EN 60825-1 and are labeled accordingly. External laboratory testing can also be arranged upon request.
