Abstract: A method is described for quantitative determination of suitability of an optical material, especially alkali halide and alkaline earth halide single crystals, for optical components exposed to high energy densities, especially of pulsed laser light at wavelengths under 250 nm. In this procedure radiation-dependent transmission of the optical material is determined at ultraviolet wavelengths by fluorescence measurements for fluorescence induced by ultraviolet radiation at these ultraviolet wavelengths. This is accomplished by a method including determining an induced fluorescence maximum of a non-linear absorption process, measuring a slope (|dT/dH|) of a functional relationship representing the dependence of the radiation-dependent transmission on fluence (H) for the induced fluorescence and determining radiation-dependent transmissions from this slope for particular fluence values.

Abstract: The apparatus for extending or lengthening a laser pulse has a beam splitter. An incident laser pulse is split by the beam splitter into at least one first partial pulse and a second partial pulse. The first partial pulse is conducted through a delaying travel path section with a number of reflectors. The apparatus is characterized by a plurality of the variable delaying travel path sections which produce different length laser beam pulses from a single incident laser pulse.

Abstract: A method is described for quantitative determination of suitability of an optical material, especially alkali halide and alkaline earth halide single crystals, for optical components exposed to high energy densities, especially of pulsed laser light at wavelengths under 250 nm. In this procedure radiation-dependent transmission of the optical material is determined at ultraviolet wavelengths by fluorescence measurements for fluorescence induced by ultraviolet radiation at these ultraviolet wavelengths. This is accomplished by a method including determining an induced fluorescence maximum of a non-linear absorption process, measuring a slope (|dT/dH|) of a functional relationship representing the dependence of the radiation-dependent transmission on fluence (H) for the induced fluorescence and determining radiation-dependent transmissions from this slope for particular fluence values.

Abstract: The apparatus for extending or lengthening a laser pulse has a beam splitter. An incident laser pulse is split by the beam splitter into at least one first partial pulse and a second partial pulse. The first partial pulse is conducted through a delaying travel path section with a number of reflectors. The apparatus is characterized by a plurality of the variable delaying travel path sections which produce different length laser beam pulses from a single incident laser pulse.

Abstract: The present invention refers to a method for the quantitative measurement of the pulse laser stability of synthetic fused silica, whereby this method avoids time-consuming and demanding measurements and saves material. First, the absorption of fused silica is measured for different energy densities, and a non-linear function ?1(H) is determined on the basis of the measured values. Second, the fused silica is subject to radiation with a higher energy density up to the point at which a constant absorption value is achieved. In the following, the absorption of the fused silica is measured at different energy densities, and a non-linear function ?2(H) is determined. The difference between the two non-linear functions indicates the increase of absorption that depends on the energy density.

Abstract: The method tests the suitability of an optical material having a radiation-induced absorption, especially of an alkali or alkaline earth halide, for production of an optical element exposed to high-energy irradiation. The method includes pre-irradiating the optical material with laser radiation until rapid damage induced in the optical material with the laser radiation is saturated; subsequently measuring fluorescence of the optical material during and/or immediately after irradiating the optical material with excitation radiation and determining the non-intrinsic fluorescence and intrinsic fluorescence present in the measured fluorescence. Suitability may be preferably determined according to a ratio of the amount of non-intrinsic fluorescence to intrinsic fluorescence. A device for performing the method including a barrier device for blocking scattered excitation radiation is also provided.

Abstract: A method is described for quantitative determination of suitability of an optical material, especially alkali halide and alkaline earth halide single crystals, for optical components exposed to high energy densities, especially of pulsed laser light at wavelengths under 250 nm. In this procedure radiation-dependent transmission of the optical material is determined at ultraviolet wavelengths by fluorescence measurements for fluorescence induced by ultraviolet radiation at these ultraviolet wavelengths. This is accomplished by a method including determining an induced fluorescence maximum of a non-linear absorption process, measuring a slope (|dT/dH|) of a functional relationship representing the dependence of the radiation-dependent transmission on fluence (H) for the induced, fluorescence and determining radiation-dependent transmissions from this slope for particular fluence values.

Abstract: The method tests the suitability of an optical material having a radiation-induced absorption, especially of an alkali or alkaline earth halide, for production of an optical element exposed to high-energy irradiation. The method includes pre-irradiating the optical material with laser radiation until rapid damage induced in the optical material with the laser radiation is saturated; subsequently measuring fluorescence of the optical material during and/or immediately after irradiating the optical material with excitation radiation and determining the non-intrinsic fluorescence and intrinsic fluorescence present in the measured fluorescence. Suitability may be preferably determined according to a ratio of the amount of non-intrinsic fluorescence to intrinsic fluorescence. A device for performing the method including a barrier device for blocking scattered excitation radiation is also provided.

Abstract: A method is described for quantitative determination of suitability of an optical material, especially alkali halide and alkaline earth halide single crystals, for optical components exposed to high energy densities, especially of pulsed laser light at wavelengths under 250 nm. In this procedure radiation-dependent transmission of the optical material is determined at ultraviolet wavelengths by fluorescence measurements for fluorescence induced by ultraviolet radiation at these ultraviolet wavelengths. This is accomplished by a method including determining an induced fluorescence maximum of a non-linear absorption process, measuring a slope (|dT/dH|) of a functional relationship representing the dependence of the radiation-dependent transmission on fluence (H) for the induced, fluorescence and determining radiation-dependent transmissions from this slope for particular fluence values.

Abstract: The present invention refers to a method for the quantitative measurement of the pulse laser stability of synthetic silica glass, whereby this method avoids time-consuming and demanding measurements and saves material. First, the absorption of silica glass is measured for different energy densities, and a non-linear function ?1 (H) is determined on the basis of the measured values. Second, the silica glass is subject to radiation with a higher energy density up to the point at which a constant absorption value is achieved. In the following, the absorption of the silica glass is measured at different energy densities, and a non-linear function ?2 (H) is determined. The difference between the two non-linear functions indicates the increase of absorption that depends on the energy density.

Abstract: An arrangement for spatially resolved acquisition of an object which is illuminated by an illumination arrangement, wherein a relative movement is generated between the illumination arrangement and the object by moving the object and/or the illumination arrangement and, in addition to at least one confocally arranged detection element for confocal acquisition of the light coming from points on the object, there is provided at least one additional detection element for the acquisition of object light at least posterior in time to the confocal acquisition. For at least two-dimensionally spatially resolved measurement of time processes, especially of fluorescence decay times, preferably at the ocular fundus, using a scanning laser ophthalmoscope, the radiation receiver is at least a series of detectors which are arranged in such a way that there is a series of additional detector elements in addition to the confocal detector element at least subsequently in the scanning direction.

Abstract: The invention relates to a shaft-type countercurrent heat exchanger in which the uppermost part of the shaft is formed by a turbulence chamber which communicates with the underlying countercurrent chamber of the shaft through a central material outlet and several gas pipes opening tangentially into the turbulence chamber, thereby improving the thermal efficiency of the heat exchanger.

Abstract: Impact resistant glass laminates formed of at least one silicate glass panel and at least one polycarbonate panel bonded together by a methacrylate resin formed from at least 50% by weight of the polymerizable mixture of 2-ethylhexyl methacrylate.

Abstract: A suspension gas preheater (hereinafter referred to in short as a suspension preheater) for fine material comprising several heat exchanger stages arranged one above the other through which material passes successively in a downward direction and through which the gas flows upwards in countercurrent thereto, is fitted with an additional heat exchanger stage which is supported alongside the vertical stack of original heat exchanger stages and which is connected to the uppermost original heat exchanger stage by a material feed system.

Abstract: Laminated safety glass wherein the adhesive binder used contains at least 50% by weight of 2-ethylhexylmethacrylate, 0.2 to 2% by weight of the binder of at least one alkylacyl peroxide and 0.005 to 0.5% by weight of the binder of at least one compound which contains a labile halogen atom, as solution in a phlegmatization agent, 0.01 to 10 ppm Cu.sup.++ -ions in the form of a copper salt soluble in the binder and 0.05 to 3% by weight of the binder of a .omega.-mercaptoalkyltrialkoxy silane.

Abstract: A vertical reaction vessel has a plurality of funnel-like constrictions dividing the vessel into individual chambers, at least one inlet for introducing fine material into the top of the uppermost of such chambers, and an opening at the bottom of the lowermost of such chambers for withdrawing heated fine material, and for introducing hot gas to be exhausted from the uppermost chamber. Guide elements for the fine material extend downward along the inner surface of at least one of the funnel-like constrictions.