Abstract: A method of manufacturing a photomultiplier tube (10) comprising a tube body (20), a photocathode (30) and an electron multiplier element (40) destined to be placed at a small distance from the photocathode (30). According to the invention the tube (10) is provided with sliding means (50) of the electron multiplier (40) parallel to the axis (22) of the tube body (20), means (50) provided with abutments (53) situated in the proximity of the said window (31).

Abstract: Electron multiplier element for secondary emission, consisting of a first metal plate (11) which has at least one multiplier hole (12) having one input aperture (13) and one output aperture (14), and a second metal plate (16) in parallel with the first plate (11) which has at least one auxiliary hole (17) disposed opposite the output aperture (14) of the multiplier hole (12). The second plate (16) being brought to an electric potential (V1) which is higher than the electric potential (V0) of the first plate. The apertures (13, 14) are such that the projection (18) of the output aperture (14) of the multiplier hole (12) in a plane which is parallel to the first metal plate (11) is at least partially located outside the corresponding projection (19) of the input aperture (13).

Abstract: Electron multiplier plate with controlled multiplication, multiplier element comprising the said plate, multiplier device comprising the said element and application of the said device to a photomultiplier tube.Secondary emission electron multiplier plate (10) of the "aperture plate" type, comprising multiplier apertures (11), each having an input side (12), an output side (13), and an efficacious multiplier partition (14) having emissive power. Multiplier plate (10) has at least one elementary multiplier pattern (15) comprising a plurality of multiplier apertures, at least the said efficacious multiplier partitions (14a) of the peripheral multiplier apertures (11a) of the pattern (15) being oriented towards the interior of the said pattern.

Abstract: Electron multiplier element (11) with secondary emission of the "apertured plate" type, characterized in that, on the one hand, it consists of a first plate (12) having holes (13), which are termed multiplier holes, in which each multiplier hole (13) defines on a first surface (14) of the said first plate (12) an aperture (15) which is termed input aperture and which is larger than the aperture (16), which is termed output aperture, which is defined on the second surface (17) of the first plate (12), and, on the other hand, consists of a second plate (22) which is parallel to the first plate (12), which also comprises holes (23) which are termed auxiliary holes the aperture (25) of which is situated on a first surface (24) of the second surface (22) opposite to the second surface (17) of the first plate (12), is substantially equal to the output aperture (16) of the multiplier holes (13) and is smaller than the aperture (26) of the said auxiliary holes (23) which are defined on the second surface (27) of the

Abstract: The invention relates to secondary-emissive microchannels which are bent to a given extent on the output side of the electrons. The said bending serves to restrict the areas where the electrons contact the channel walls to a small zone at the end of the electron multiplication and before the departure of the secondary electrons. The energy of the output electrons is thus dispersed very little.The emission of electrons can then be controlled by means of low electrical voltages which can be readily switched. The said partially curved microchannels are incorporated in electron tubes in the advantage of the ease of control, is utilized.

Abstract: Method of manufacturing image display apparatus having a photocathode which is proximity focussed with respect to a micro-channel plate, comprising the steps of: positioning a photocathode substrate adjacent to the input face of a microchannel plate, the substrate having a surface facing the microchannel plate which may be altered by ion radiation bombardment; directing ion radiation from the channels of the microchannel plate by imposing a suitable voltage potential across the microchannel plate in a vacuum atmosphere to alter the surface of the substrate in a pattern of individual areas corresponding to the channels of the microchannel plate; forming a bowl-shaped photo-emissive recess at each of the altered individual areas; and spacing the substrate from the microchannel plate by a distance which results in each bowl-shaped photo-emissive recess being proximity focussed on the input aperture of the same channel that defined the individual area at which the bowl-shaped photo-emissive recess was formed.