U.S. Philips Corporation

Petrus H Trompenaars

Nicolaas Lambert

Siebe Tjerk De Zwart

Gerardus G Van Gorkom

Gerardus A Vrijssen

Bernardus H Hendriks

Edwin A Montie

Theunis S Baller

Edward C Cosman

Antonius J Rademakers

Johannes Cornelis Driessen

Henricus J Ligthart

Peter Martens

Flat-panel type picture display device having a luminescent screen and a large number of electron propagation ducts operating by means of electron wall interaction. Electrons are withdrawn from the ducts by means of an addressing system, whereafter these electrons are directed towards desired locations on the luminescent screen. An apertured spacer plate of electrically insulating material for passing electrons is arranged between the addressing system and the screen. To enable large voltage differences to be applied across the dimension of thickness of the spacer plate, the spacer plate is provided with a high-ohmic layer, or with a pattern of a low-ohmic material, or with an equalization layer at one side and with a low-ohmic layer at the other side, and at least the walls of the apertures are preferably coated with a material having a low secondary emission.

Flat-panel type picture display device with electron propagation ducts

A picture display device has a vacuum envelope and is provided with a face plate whose inner side supports a luminescent screen, a rear wall situated at a short distance therefrom, and the space in-between accommodating a plurality of electron sources, which cooperate with a plurality of electron transport duct including dielectric walls fro transporting, through vacuum, the produced electrons towards positions at a small distance from the luminescent screen. The display device further includes means for reducing the effects of undesired charge transfer of the duct walls, which are provided to improve the start-up and/or steady state electron transport conditions. Specifically, the outer sides of the duct rear walls are provided with a conductor to which an initiation potential is applied, which is equal to or higher than the potential applied for producing the electron transport field.

Flat-panel type picture display device

A picture display device having a flat vacuum envelope which is provided with a transparent face plate with a luminescent screen and with a rear wall, which display device has an electron supply section with an electron source for emitting electron currents in a direction parallel to the face plate, and an active selection electrode section with first, preselection, electrodes and second, fine-selection, electrodes, located closer to the screen, for directing each electron current towards desired pixels on the luminescent screen. The fine-selection electrodes are divided into groups and corresponding fine-selection electrodes of at least two groups are interconnected in a series or parallel arrangement in such a way that the technology of providing these electrodes is as simple as possible and/or the possible fine-selection electrode patterns are such that the number of required selection drivers can be reduced considerably.

Picture display device having a flat vacuum tube

A picture display device has a vacuum envelope and is provided with a face plate whose inner side supports a luminescent screen, a rear wall situated at a short distance therefrom, and the space in-between accommodating a plurality of electron sources, which cooperate with a plurality of electron transport ducts including dielectric walls for transporting, through vacuum, the produced electrons towards positions at a small distance from the luminescent screen. The display device further includes means for reducing the effects of undesired charge transfer of the duct walls, which are provided to improve the start-up and/or steady state electron transport conditions. Specifically, the outer sides of the duct rear walls are provided with a conductor to which an initiation potential is applied, which is equal to or higher than the potential applied for producing the electron transport field.

The thin-type display device (1) with a vacuum envelope has a transparent front wall (3), which is provided with a display screen, and at least an electron source (5) and a duct structure, which cooperates with the electron source (5) and which extends substantially parallel to the front wall (3). Ducts (6, 6', 6') of the duct structure serve as electron-propagation means and are provided with walls (11, 11', 11') of an electrically insulating material having a secondary emission coefficient which is suitable for electron propagation. In the display device (1) 1.ltoreq.s/w.ltoreq.5 and s.multidot.w.gtoreq.5 mm.sup.2, where s is the depth of the ducts (6, 6', 6') and w is the width of the ducts (6, 6', 6'). Preferably, the width w.gtoreq.1.5 mm and the depth 3.5.ltoreq.s.ltoreq.15 mm. The voltage difference over the length of the ducts (6, 6', 6'), measured parallel to the front wall (3), is less than 75 V/cm, preferably less than 40 V/cm.

Thin-type display device

A display device including a vacuum envelope having an electroluminescent screen, an electron source and a branched network of electron-transport ducts having at least one entrance for electrons and at least two exits at end portions of the network. An electron current flows from the entrance to a desired one of the exits via nodes in the network. The network exits corresponding to one entrance form a two or three dimensional array of exits. Preferably, the distance, via the network, between an entrance and its corresponding exits is equal.

Flat panel display having electron transport ducts with equal

A flat display device is provided with a wire cathode or wire cathodes and with apertures which allow passage of electrons emitted by the wire cathode. The wire cathode is stretched in a wire-cathode support having positioning grooves for the wire cathode. This support engages the element in which the passages are made. The support and the element are provided with corresponding contacting surfaces.

Display device having a support structure for a wire cathode

Flat-panel type picture display device having a face plate with a luminescent screen at the inner side and, arranged at a short distance therefrom, a rear plate adjoined by a large number of electron transport ducts operating by means of wall interaction of electrons. An active selection structure for directing electrons from transport ducts towards pixels on the luminescent screen comprises an apertured preselection plate and an apertured fine-selection plate, each preselection aperture being associated with at least two fine-selection apertures. Special auxiliary (or dummy) electrodes between the preselection plate and the selection plate, and/or a special geometry of the preselection apertures ensure that colour purity and contrast are maximal.

Flat-panel type picture display device with electron transport ducts and

A flat-panel type picture display device having a face plate with a luminescent screen at the inner side and, arranged at a short distance therefrom, a rear wall adjoined by a large number of electron transport ducts operating by means of wall interaction of electrons. A selection structure for withdrawing electrons from transport ducts and for directing them towards pixels on the luminescent screen comprises a preselection structure provided with preselection locations and a fine-selection plate provided with fine-selection apertures, each preselection location being associated with at least two fine-selection apertures. To improve contrast and/or color purity, an apertured obstruction plate forming chicanes in the electron paths is arranged between the preselection plate and the fine-selection plate.

A display device comprising electron-transport ducts having entrance apertures for electrons and means for generating electrons and injecting electrons into the transport ducts via the entrance apertures. Measures have been taken to improve the picture quality. For example, the location of the entrance aperture is not the same for each transport duct, but instead shows a variation. This enables an improved control of the electron flow in the transport ducts to be achieved; in particular crosstalk between the transport ducts can be reduced.

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Eindhoven, Netherlands

Petrus H Trompenaars