Considering the movement of the laser source for classification in IEC 60825-1

Within the development process of the international laser product safety standard IEC 60825-1 towards a more appropriate description of complex new laser devices, the case of a moving laser source (such as mounted on a vehicle) has to be considered. It is currently implied to handle such a case as scanning radiation with a stationary aperture stop, which is not restrictive enough in some cases: assuming an observer which is moving at the same speed as the vehicle, the emission duration cannot be reduced as it is done for the case of a radially scanning laser. We therefore suggest the modification of the standard which should consider a moving aperture which leads to the consideration of the full classification time base. Also a measurement aperture does not need to be placed at a distance at which no observer can be expected (due to the speed of the laser source). For situations of a relative speed of zero (moving observer) the worst case distance has to be estimated by mechanical criteria. The proposal is similar to the consideration of a virtual enclosure as for instance defined by distance sensors, but here the speed of the platform is the basis for the classification distance.