Abstract: The invention relates to a method for transferring the wave front of primary light pulses with a specifiable first pulse duration and/or energy to secondary light pulses with a specifiable second pulse duration and/or energy. For an easy realization of a wave front transformation of this type, it is suggested according to the invention to store respectively in a first time segment the wave fronts of the primary light pulses with the aid of reference light pulses as spatial hologram in a holographic memory. In a following second time interval, this stored, spatial hologram is then read out with the aid of reconstruction light pulses, having the second pulse duration and energy, wherein the reconstruction light pulses for reading out the hologram have the same wavelength and wave front as the reference light pulses.

Abstract: A device for protecting an optical component from a laser beam. The device includes a carrier which is light-pervious in a predetermined spectral range and is positionable in an expected path of a laser beam directed to the optical component; and a metal oxide film applied to the carrier. The film is light-pervious in the same spectral range and is oriented such as to intercept a laser beam directed to the optical component.

Abstract: An apparatus for determining the position of a hollow section system which is pressed forward. Measuring apparatus are arranged one behind the other in the hollow section system. Measuring points are also provided. Each measuring apparatus has a light source for marking the position, a position detector, and an optical system. The measuring apparatus are arranged in such a way that the projection of the light source of each measuring apparatus takes place to the position detector of the respective adjacent measuring apparatus. The measuring apparatus are connected to each other for the transmission, and receiving, of signals present at the position detectors. The coordinates of the measuring apparatus can be determined from the signals, and from this the spatial position of the hollow section system can be determined.