Abstract: The invention relates to a switching device having shorter switching times. The device comprises a switchable layer (3), which is switched between a reflecting and an absorbing state by changing a hydrogen content of the switchable layer (3). Applying a DC voltage on electroconductive layers (11, 13) changes the hydrogen content. These electroconductive layers (11, 13) sandwich a stack of layers comprising the switchable layer (3) and a hydrogen storage layer (9). The hydrogen storage layer comprises essentially the same compounds as the switchable layer (3), viz. LMgHx and preferably GdMgHx. The storage layer may be made thin, leading to relatively short hydrogen transportation times and a relatively fast display. The device may be further improved by applying a scattering foil.

Abstract: A description is given of a switching device (1) comprising a transparent substrate (3) and a switching film (5) which incldes a hydride of a trivalent metal, such as gadolinium, and which is covered with a palladium layer (7). Between the substrate (3) and the switching film (5) a thin magnesium layer (4) is interposed. By exchange of hydrogen, the switching film can be reversibly switched from a transparent state to a highly reflective state. The conversion between both states is reversible, and this phenomenon can be used, for example, in a luminaire or for climate control.

Abstract: A Method (1) for Rapid Thermal Processing of a wafer (7), wherein the wafer (7) is heated by lamps (9), and the heat radiation is reflected by an optical switching device (15,17) which is in the reflecting state during the heating stage. During the cooling stage of the wafer (7), the heat is absorbed by the switching device (15,17), which is in the heat-absorbing state. The switching device includes a switching film of a trivalent metal, such as gadolinium, which is capable of forming hydrides by an exchange of hydrogen. Dependent on the hydrogen concentration of the hydrides, the film reflects or absorbs heat. The hydrogen content in the switching film can be changed by varying the partial pressure of hydrogen, or, preferably, by varying the potential of the switching film forming part of a stack of layers in an electrochemical cell.

Abstract: A description is given of an optical switching device (1) comprising a transparent substrate (3), a switching film (5) of a hydride compound of a trivalent transition or rare earth metal having a thickness of 300 nm, and a palladium capping layer (7) having a thickness of 30 nm. The capping layer is in contact with hydrogen. An electric current through the switching film (5) can be switched on and off between the terminals (9, 11). Joule heating of the switching film (5) causes a rapid transition from the transparent trihydride state to the absorbing dihydride state. By switching off the current, the switching film (5) cools down, which results in the formation of the absorbing dihydride state. The conversion between both states is reversible and can be repeated many times. The device can be used for controlling light beams, or it can be used in or for a display. Optionally, cooling of the switching film (5) is obtained with a Peltier element in thermal contact with the switching film (5).

Abstract: A furnace (1) for Rapid Thermal Processing of a wafer (7), characterized in that the wafer (7) is heated by lamps (9), and the heat radiation is reflected by an optical switching device (15,17) which is in the reflecting state during the heating stage. During the cooling stage of the wafer (7), the heat is absorbed by the switching device (15,17), which is in the heat-absorbing state. The switching device comprises a switching film of a trivalent metal, such as gadolinium, which is capable of forming hydrides by an exchange of hydrogen. Dependent on the hydrogen concentration of the hydrides, the film reflects or absorbs heat. The hydrogen content in the switching film can be changed by varying the partial pressure of hydrogen, or, preferably, by varying the potential of the switching film forming part of a stack of layers in an electrochemical cell.

Abstract: A description is given of a switching device (1) comprising a transparent substrate (3), a switching film (5) including hydrides of gadolinium or other trivalent metal, and magnesium, covered with a palladium layer (7). By exchange of hydrogen, the switching film can be reversibly switched from a transparent state to a mirror-like state with zero transmission via an intermediate black absorbing state. The conversion between both states is reversible, and this phenomenon can be used, for example, in an optical switching element or sun roof.

Abstract: In the case of simultaneous diffraction and fluorescence measurements in an apparatus for X-ray analysis comprising only one X-ray tube, a problem is encountered in that due to the presence of the collimators required for the fluorescence measurements only a very low X-ray power reaches the detectors, so that very long measuring times and/or an unfavorable signal-to-noise ratio occur. As a result, the detection limit for given measurements (low concentration of an element and/or light elements to be detected) becomes too high or the use of a (large and expensive) high-power X-ray tube is required. The invention utilizes a line focus tube 10 in combination with a single-slit collimator 14 for irradiating the sample 2, the fluorescence section 40 being constructed so as to have a plane or cylindrical analysis crystal 42 in combination with a location-sensitive detector 44. The diffraction measurements are performed by means of a conventional diffraction arrangement 24.

Abstract: A description is given of a switching device 1 comprising a transparent substrate 3, a switching film 5 of gadolinium having a thickness of 200 nm and a palladium layer (7) having a thickness of 10 nm. Under the influence of hydrogen gas, a transparent semiconductive layer (5) of GdH.sub.x (x>2) is formed which can be converted into a non-transparent layer of GdH.sub.x (x<2) by means of evacuation. The conversion between both compositions is reversible, and this phenomenon can for example be used in an optical switching element, a hydrogen sensor and thin displays.

Abstract: An X-ray analysis apparatus comprises a dispersive system of crystals for monochromatizing an incoming beam in a diffractometer or for analyzing an X-ray beam in an X-ray spectrometer. The system of crystals comprises crystals whose crystal lattice planes do not extend parallel to effectively reflective crystal surfaces. As a result, a substantially higher effective radiation intensity can be obtained, for example notably for (220) crystal faces in germanium.