Abstract: The invention is related to a method for producing a collimator comprising an X-ray transparent substrate. The innovative method comprises the steps of: forming a slit in the substrate, wherein the slit has first and second side walls; filling the slit with an X-ray absorbing material so that the absorbing material extends from the first side wall to the second side wall; removing part of the X-ray absorbing material thereby forming a second slit that extends from the remaining absorbing material to the second side wall; filling the second slit with X-ray transparent material; removing part of the X-ray transparent material, thereby forming a third slit extending from the remaining transparent material to the second side wall; and finally filling the third slit with X-ray absorbing material. In accordance with the present invention a collimator can be produced having any desired aspect ratio.

Abstract: The invention is related to a method for producing a collimator comprising an X-ray transparent substrate. The innovative method comprises the steps of: forming a slit in the substrate, wherein the slit has first and second side walls; filling the slit with an X-ray absorbing material so that the absorbing material extends from the first side wall to the second side wall; removing part of the X-ray absorbing material thereby forming a second slit that extends from the remaining absorbing material to the second side wall; filling the second slit with X-ray transparent material; removing part of the X-ray transparent material, thereby forming a third slit extending from the remaining transparent material to the second side wall; and finally filling the third slit with X-ray absorbing material. In accordance with the present invention a collimator can be produced having any desired aspect ratio.

Abstract: A radiation detector comprises two electrode arrangements, each including a dielectric substrate and an electrically conducting layer formed on a first surface of respective dielectric substrate, wherein the electrodes are oriented such that the conducting layers are facing each other. A dielectric spacer is provided to hold the electrodes at a distance from each other to thereby define an inter-electrode space, which, during use, is filled with an ionizable gas. The electrodes are held at respective electric potentials to drift electrons released during ionization of the ionizable gas by external radiation towards one of the electrodes for detection.

Abstract: A detector for detection of ionizing radiation comprises a cathode; an anode; an ionizable gas arranged between these electrodes; a radiation entrance arranged such that ionizing radiation can enter and ionize the ionizable gas; and a readout arrangement. A voltage across the electrodes causes electrons created during ionization of the gas to drift towards the anode, where the readout arrangement detects them. To reduce the risk of occurrence of sparks, and/or to reduce the energy in occurring sparks, one of the cathode and anode has at least the surface layer facing the other electrode made of a material having a resistivity of at least 5×10−8 &OHgr;m.

Abstract: A radiation detector comprises two electrode arrangements, each including a dielectric substrate and an electrically conducting layer formed on a first surface of respective dielectric substrate, wherein the electrodes are oriented such that the conducting layers are facing each other. A dielectric spacer is provided to hold the electrodes at a distance from each other to thereby define an inter-electrode space, which, during use, is filled with an ionizable gas. The electrodes are held at respective electric potentials to drift electrons released during ionization of the ionizable gas by external radiation towards one of the electrodes for detection.

Abstract: A method and apparatus for radiography and also a detector for detecting incident radiation. In the method and the apparatus X-rays (9) are emitted from an X-ray source (60). The X-rays which have interfered with an object to be imaged are detected (62) in a detector (64). The detector (64), which detects incident radiation includes a gaseous avalanche chamber, including electrode arrangements between which a voltage is applied for creating an electrical field, which causes electron-ion avalanches of primary and secondary ionization electrons released by incident radiation.

Abstract: A detector for detection of ionizing radiation comprises a cathode; an anode; an ionizable gas arranged between these electrodes; a radiation entrance arranged such that ionizing radiation can enter and ionize the ionizable gas; and a readout arrangement. A voltage across the electrodes causes electrons created during ionization of the gas to drift towards the anode, where the readout arrangement detects them. To reduce the risk of occurrence of sparks, and/or to reduce the energy in occurring sparks, one of the cathode and anode has at least the surface layer facing the other electrode made of a material having a resistivity of at least 5×10−8 &OHgr;m.

Abstract: A method and apparatus for radiography and also a detector for detecting incident radiation. In the method and the apparatus X-rays (9) are emitted from an X-ray source (60). The X-rays which have interfered with an object to be imaged are detected (62) in a detector (64). The detector (64), which detects incident radiation includes a gaseous avalanche chamber, including electrode arrangements between which a voltage is applied for creating an electrical field, which causes electron-ion avalanches of primary and secondary ionization electrons released by incident radiation.