Abstract: The invention relates to a method and an apparatus for the direct and precise measurement of the power and/or energy of a laser beam, which make a measurement possible even in areas close to the focus of a laser beam, A device is proposed for this purpose that contains a radiation sensor, an expansion device, and a support mount. The radiation sensor has a receiving surface and is configured for the generation of an electrical signal, which is dependent on the power of the laser beam or the energy of the laser beam. The expansion device and the radiation sensor are positioned on the support mount at a distance from one another. The expansion device is configured in such a way as to increase the angle range of the laser beam. The laser beam propagates to the radiation sensor with an increased angle range. A diameter of the laser beam propagated on the receiving surface is greater than a diameter of the laser beam in the area of the expansion device.

Abstract: The invention relates to a method and an apparatus for the direct determination of spatial dimensions of a light beam with high precision and short measuring period, which are also suitable for the measuring of laser beams with high power in the range of the beam focus. For this purpose, an apparatus is proposed that includes a beam scanner, at least one light sensor, a movement device for the execution of a relative movement between the light beam and the beam scanner, and a device for the signal recording of a temporally variable signal of the light sensor. The beam scanner comprises at least one scanning body with at least three sampling areas, which extends along sampling lines. The sampling areas are configured for the extraction of linear or strip-shaped light samples from a cross-section of the light beam. Several scanning surfaces are defined by the sampling lines of the sampling areas, each spanned by a movement vector of the relative movement.

Abstract: Apparatus for determining geometrical parameters of a laser beam includes an optical system, a device for output coupling radiation, a beam diagnostic device, and a reflector element. The optical system focuses the laser beam into a processing region. The device for output coupling radiation couples out radiation that runs through the optical system in a direction opposite to a direction of the laser beam. The reflector element has a first surface which is partially reflecting and curved, where the curvature is equal to a mean curvature of a wave front of the laser beam in a positioning region of the reflector element.

Abstract: A laser power meter has a laser-radiation absorber body of metal formed with a rotationally symmetrical depression open at the radiation-receiving side of the body. At the bottom of the depression a copper reflector of a cone shape is received. The body can be connected to a lid housing the detection and display circuitry by a joint which can be locked and from which tubes can run to the body and lid to carry the electrical conductors.