JPS6344692A - Control of plasma electron source for flat type display - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a physical display using discharge plasma as an electric source.

[Prior art] As a planar electron source in a new type of mo-screen display, electrons present in discharge plasma are extracted using an electrode with holes or striped electrodes to which positive pressure is applied, and the electrons are brought to a high level. It is known that a phosphor can be accelerated with an electric field to cause it to emit light. (Refer to Japanese Patent Publication No. 55-27422) [Problems to be Solved by the Invention] In the above-mentioned display, abnormal glow radiation is used as a planar electron source, but if the discharge current is less than the appropriate value, A sufficient electron flow cannot be obtained, resulting in insufficient brightness on the display surface and even extreme non-uniform brightness. Also,
If the discharge current is excessive, the cathode material will scatter due to sputtering from the cathode surface and adhere to the inner wall of the container and other electrodes, shortening the life of the device. 11 in F- to achieve good display quality and design life by keeping it at 11! However, no means have been proposed to achieve this.

[Means for Solving the Problems] As is well known, the abnormal glow discharge for generating a surface electron source is in the current range B in FIG.

Note that the range A is the normal glow discharge range, and the range C is the arc discharge range.

The degree of abnormal glow discharge can be quantitatively known by superimposing a microvoltage or a total microcurrent on the discharge voltage or discharge current and detecting the operating resistance R = ΔV/Δ1.6 The present invention has the following features: They discovered that by controlling the discharge voltage so as to keep this value at a predetermined value, it is possible to maintain an appropriate abnormal glow discharge in the display element.

Next, referring to FIG. 1, in FIG. 0 specifically explaining the present invention, l is a mo-face type display element using a plasma electron source, 2 is a cathode, and 3 is an anode. The cathode 2 is connected to a cathode-side power source 4 through a load resistor RL in a direct current manner, and to an alternating current power source A through a capacitor 〇. Yang J4i
3 is connected to the anode side power source 5 via a current detection resistor R3. The AC voltage component applied to the cathode appears at the anode end via the discharge operating resistance Rg, and is transferred to the control circuit section 6.
The voltage is increased by ``t'', converted to direct current, and compared with the reference voltage.
The output controls the cathode-side variable DC power supply 11 to maintain the discharge operating resistance as constant as possible. That is, the operating resistance of discharge is controlled to be maintained within a predetermined range. In this case, it is also possible to configure the control circuit section 6 using a microcomputer.

In the figure, 7 is a superimposed amplifier, 8 is a direct current converting circuit, and 9 is a direct current converting circuit.
1 is a comparator, and 10 is a base thread voltage generation circuit, which constitutes the control circuit section 6.

The present invention is characterized in that the operating resistance of the plasma electron source is detected in this manner, and thereby the operating resistance of the discharge is controlled within a predetermined range. to be done.

[Effects of the Invention] The present invention measures the operating resistance of the plasma electron source as described in L, and controls the cathode-side variable DC power supply 11 so that the operating resistance becomes a predetermined value. It is possible to properly maintain the state of abnormal glow emission Ig, which is the electron source, thereby ensuring the brightness of the display surface and its uniformity,
In addition, since the sputtering phenomenon of the cathode is kept to a minimum, the life of the device can be ensured.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, and FIG. 2 is an explanatory diagram of discharge. In the figure, l, mo-screen display element, 26 cathodes,
3. Anode, 4. Cathode side power supply, 5, Anode side power supply,
6. Control circuit section, 11, variable DC TL source part @8

Claims (1)

[Claims] (1) A flat display comprising means for detecting the operating resistance of a plasma electron source for a flat display during the display operation period or blanking period, and means for controlling the operating resistance within a predetermined range based on the detection result. Driving method.