MXPA96005136A - Catodi rays tube - Google Patents

Abstract

The present invention relates to a cathode ray tube that includes an electron gun for emitting an electron beam, a deflection or deflection yoke, which deflects the electron beam emitted, and a corrector that includes electromagnets installed on the sides of above and below, and from the right and from the left, from a separator of the deflection yoke, to correct the shape of the section of the emitted electronic beam. The resolution of the image can be improved by correcting the distortion of the electron beam section, which is landed on the edge of a fluorescent film.

Description

CRT FIELD OF THE INVENTION The present invention relates to a cathode ray tube, and more particularly to a cathode ray tube having a corrector to prevent distortion of the section of an electron beam, which is emitted from an electron gun, deflected by a deflection yoke and landed on a fluorescent film.

BACKGROUND OF THE INVENTION In general, a cathode ray tube forms imaging elements or pixels by landing the electron beam emitted from the electron gun which is sealedly coupled to the neck portion thereof, on the fluorescent film formed within a panel, being deviated selectively by the yoke of deflection and forms an image with the collective image elements. The electron beam must be landed correctly, on the REF: 23354 fluorescent point of the fluorescent film, to obtain a good image. However, the light spot of the electron beam that is landed on the fluorescent film is distorted, since the deflection or deflection coil, of the deflection yoke, forms non-uniform deflection magnetic fields, and the geometric curvature of the interior of the panel It distorts. The deflection magnetic field, of the deflection yoke, which deflects the electron beam, as shown in Figure 1, consists of a magnetic field 11 for cushion distortion, formed by a horizontal deflection coil and a magnetic field 12 of distortion in barrel, formed by a vertical deflection coil. As shown, the magnetic fields applied respectively to the electron beams, red (R), green (V), and blue (A), emitted from an electron gun (not shown) are all, not uniform. Therefore, when the electron beam that receives a deflection force, which passes through the magnetic field 11 for cushion distortion, non-uniform, and the magnetic field 12 for barrel distortion, it is landed on a fluorescent film 200 of a panel (not shown), the light spot of the electron beam is distorted by a Lorentz effect and is elongated in the diagonal direction of the image at the edge of the fluorescent film 200, as shown in Figure 2. For To solve this problem, a conventional method distorts the section of the electron beam emitted from the electron gun, in the opposite direction of the non-uniform magnetic direction of the deflection yoke, and differentiates the length of the focus of the electron beam that scans the center of the electron beam. 200 electron beam fluorescent focus film scanning the edge of the fluorescent film 200. This method distorts the electron beam section is that it passes through the electronic lens (not shown) installed between the electrodes of the electron gun in the opposite direction of the distortion, by means of the deflection yoke, making the electronic lens have the focusing and emission power, which operate respectively in the vertical and horizontal directions. However, the electronic lens to distort the electron beam in this way complicates the fabrication of the electron gun, since the shape of the electron beam passage hole, formed in the electrodes of the electron gun, must be changed. Therefore, there are limitations in changing the section of the electron beam using the difference between the focusing power and the emission power of the electronic lens.

BRIEF DESCRIPTION OF THE INVENTION An object of the present invention is to provide a cathode ray tube, designed to prevent distortion of the light spot of the electron beam scanned at the edge of a fluorescent film, by correcting the distortion of the electron beam section emitted from a gun of electrons Another objective of the present invention is to provide a cathode ray tube designed to improve the resolution, preventing elongation of the shape of the electron beam section, which is made to land on the edge of the fluorescent film. To achieve the objective, a cathode ray tube is provided comprising an electron gun for emitting an electron beam, a deflection or deflection yoke, which deflects the emitted electronic beam, and correction means including electromagnets installed on the sides. from above and below and from the right and from the left, from a separator of the deflection yoke, to correct the shape of the section of the emitted electronic beam. In accordance with another aspect of the present invention, there is provided a cathode ray tube comprising an electron gun, for emitting an electron beam, a cone portion installed with a deflection yoke deflecting the electron beam emitted, and means for correction including electromagnets installed on the top and bottom sides and on the right and left sides of the cone portion, to correct the section of the emitted electron beam.

BRIEF DESCRIPTION OF THE DRAWINGS The above objects and advantages of the present invention will become more readily apparent, by describing in detail a preferred embodiment thereof with reference to the accompanying drawings in which: Figure 1 shows a magnetic field that is formed by the vertical and horizontal deflection coils of a general deflection yoke; Figure 2 shows the section of the electronic beam which is made to land on the edge of the fluorescent film, and which is deflected by a deflection yoke in a conventional cathode ray tube; Figure 3 is an enlarged side view of a part of a cathode ray tube, in accordance with the present invention; Figure 4 shows an example of a corrector of the cathode ray tube, in accordance with the present invention; Figure 5 shows another example of a cathode ray tube corrector, in accordance with the present invention; Figure 6 is a sectional or sectional view, showing the section of the electronic beam, which is corrected by the corrector of the cathode ray tube, in accordance with the present invention; Y Figure 7 shows the state in which the electronic beam, corrected by the cathode ray tube corrector, in accordance with the present invention, is landed on the fluorescent film.

DETAILED DESCRIPTION OF THE INVENTION In Figure 3 a modality of a cathode ray tube is shown, in accordance with the present invention. The cathode ray tube includes a panel 20 within which a fluorescent film 21 is formed, a neck portion 31 which is coupled to the panel 20 and has an electron gun 33 and a deflection yoke 34, and a funnel 30 having a conical portion 32. The deflection yoke 34 has a corrector 50 which is a property or peculiarity characteristic of the present invention. The corrector 50 is attached to the deflection yoke 34 and compensates the section of the electron beam emitted from the electron gun 33. The corrector 50 can be fixed to the neck portion 31 of the cathode ray tube through a joint or a separate fixing member (not shown). The constitution of the corrector, according to the present invention, is shown in Figure 4. Referring to the drawings, the corrector includes the electromagnets 51, 52, 53 and 54, respectively, installed on the top and bottom sides and on the right and on the left, of the circumference of the separator 34a of the deflection yoke. The respective electromagnets 51, 52, 53 and 54 include iron pieces 51a, 52a, 53a and 54a, respectively, and a coil 55 continuously wound on the iron pieces. Also, as shown in Figure 5, the electromagnets 61, 62, 63 and 64 can include iron pieces 61a, 62a, 63a and 64a and the coils 65a, 65b, 65c and 65d, independently wound on the respective pieces of iron . The electromagnets 51, 52, 53 and 54 of Figure 4 can be installed spaced apart from each other by a predetermined angle around the circumference of the spacer 34a, the conical portion 32 of Figure 3 or the neck portion 31 of the Figure 3, as necessary. The voltage applied to the coil 55 is preferably applied synchronously with the deflection signal of the deflection yoke. In the operation or operation of the cathode ray tube according to the present invention, constituted as indicated above, if the electron beam emitted from the electron gun 33 of Figure 3 is deflected by the deflection yoke 34, and is by scanning the edge of the fluorescent film 200 of Figure 2, the voltage that is in synchrony with the deflection signal is applied to the coil 55 (Figure 4) of the corrector 50 (Figure 3). With the voltage thus applied to the coil 55, a magnetic field is formed around the respective iron pieces 51a, 52a, 53a and 54a. The section 100 of the electron beam emitted from the electron gun 33 is lengthened vertically and horizontally through the magnetic field as shown in Figure 6., since the force is exerted outward in the upper and lower portions and the right and left portions thereof. Therefore, as shown in Figure 7, the section of the electron beam can be prevented from being diagonally stretched, by correcting the distortion of the electron beam section, by scanning the edge of the fluorescent film 200 in the diagonal directions. The respective electromagnets 51, 52, 53 and 54 of the corrector 50 can independently correct the distortion of the electron beam section. As described above, the cathode ray tube according to the present invention can improve the resolution of the image formed at the edge of the fluorescent film, since the distortion of the electron beam section, grounded on the fluorescent film is prevented. which is due to the non-uniform magnetic field and occurs when the electron beam emitted from the electron gun is deflected by the deflection yoke and explores the respective fluorescent film. The present invention is not restricted to the above embodiment, and it is clearly understood that any person skilled in the art can make possible many variations that are within the scope and spirit of the present invention.It is noted that in relation to this date, the method known by the applicant to carry out the aforementioned invention, is the conventional method for the manufacture of the objects to which it relates. Having described the invention as above, the content of the following is claimed as property:

Claims (8)

1. A cathode ray tube, characterized in that it comprises: an electron gun for emitting an electronic beam; a yoke of deflection or deviation, which deflects the emitted electronic beam; correction means including electromagnets installed on the top and bottom sides and on the right and left sides of a deflection yoke separator, to correct the shape of the emitted electron beam section.

2. A cathode ray tube according to claim 1, characterized in that a voltage applied to the electromagnets is synchronized with a deflection or deflection signal, applied to the bending yoke.

3. A cathode ray tube according to claim 1, characterized in that the electromagnets comprise pieces of iron, respectively installed on the top and bottom sides, and on the right and left, of the separator, and a coil wound continuously on those parts. of iron .

4. A cathode ray tube according to the rei indication 1, characterized in that the electromagnets comprises pieces of iron, installed respectively on the top and bottom sides and on the right and left, of the separator, and coils that are independently wound on the respective pieces of iron.

5. A cathode ray tube, characterized in that it comprises: an electron gun, for emitting an electronic beam; a conical portion installed with a deflection or deflection yoke, which deflects the emitted electronic beam; and correction means including electromagnets installed on the top and bottom sides, and on the right and left, of the conical portion, to correct the section of the emitted electron beam.

6. A cathode ray tube according to claim 5, characterized in that the voltage applied to the electromagnets is synchronized with the deflection signal applied to the deflection yoke.

7. A cathode ray tube according to claim 5, characterized in that the electromagnets comprise iron pieces, installed respectively on the top and bottom sides and on the right and left, of the conical portion, and a coil continuously wound on those pieces of iron.

8. A cathode ray tube according to claim 5, characterized in that the electromagnets comprise iron pieces, installed respectively on the top and bottom sides, and on the right and left, of the separator, and coils that are independently wound on the sides. respective pieces of iron.