JP2000023178A - Crt display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a CRT display device for automatically detecting degradation from color purity at the time of adjustment and correcting the degradation of the color purity by a calculated color purity correction current. SOLUTION: A temperature around a CRT 1 and the hue and brightness of image signals displayed at the CRT 1 are detected in a detection element 3, the detected respective parameters and the respective parameters at the time of adjusting the CRT 1 stored in a storage circuit 4 are compared in a control circuit 5 and a color purity change amount is calculated. By the calculated change amount of the color purity, a color purity correction amount at the time of making a unit current flow to a color purity correction coil 2 stored in the storage circuit 4 and horizontal and vertical synchronizing signals, the current to be made to flow to the color purity correction coil 2 is calculated in the entire area of a screen. Based on the calculated result, a driving circuit 6 makes the current flow to the color purity correction coil 2 and the color purity is corrected in the optional direction of a horizontal direction within a display screen.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a CRT display device, and more particularly to a CRT display device provided with a color purity correcting means.

[0002]

2. Description of the Related Art In a conventional CRT display device, as shown in FIG. 4, an opening angle .theta. Formed by two color purity correcting two-pole magnets 202A and 202B arranged at a neck portion of a CRT 201 is changed. , The strength of the magnetic field, and the axial angle θ of the two-pole magnets 202A, 202B.
2, the direction of the magnetic field is adjusted to correct the deterioration of color purity. In the case of a CRT having a slot-type shadow mask and an aperture grill, as shown in FIG. As shown in 6,
2 pole magnet 2 in the same horizontal direction in the display screen
02A and 202B.

[0003]

However, in the conventional CRT display device, when the CRT adjusted by the color purity correcting two-pole magnet is placed under an extreme temperature change under a predetermined condition, the shadow mask is not used. Due to the effects of doming and variations in products, there have been problems such as deterioration of color purity and color unevenness.

Accordingly, an object of the present invention is to provide a CRT display device which corrects the deterioration of color purity by using a color purity correction current which automatically detects a deterioration from the color purity at the time of adjustment.

[0005]

In order to solve the above-mentioned problems, a CRT display device according to the present invention comprises a CRT and a CR.
A detecting element for detecting the color and brightness of the image displayed on T and detecting the temperature around the CRT; and the color of the image in association with the temperature around the CRT detected by the detecting element. And a control circuit for calculating a color purity correction current value from the hue and brightness of the image displayed on the CRT based on the parameters stored in the storage circuit. A drive circuit for generating a color purity correction current from the color purity correction current value calculated by the control circuit; and a drive circuit formed at an upper and lower position perpendicular to the tube axis of the neck portion of the CRT, and And a color purity correction coil for correcting the color purity of the image.

[0006]

Next, a CRT display device according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a CR according to an embodiment of the present invention.
It is a block diagram of a T display device.

FIG. 2 shows a CR according to an embodiment of the present invention.
FIG. 3 is an external view of a color purity correction coil of the T display device.

FIG. 3 shows a CR according to an embodiment of the present invention.
FIG. 5 is an explanatory diagram of a color purity correction direction during operation of the T display device.

As shown in FIG. 1, a CRT display device according to an embodiment of the present invention detects a CRT 1, a color tone and a brightness of an image displayed on the CRT 1, and displays a CR.
A detecting element 3 for detecting the temperature around T1; a storage circuit 4 in which parameters of the hue and brightness of the image are stored in advance in association with the temperature around the CRT 1 detected by the detecting element 3; A control circuit for calculating a color purity correction current value from the hue and brightness of the image displayed on the CRT based on the parameters stored in the CRT, and a color purity based on the color purity correction current value calculated by the control circuit. A drive circuit 6 for generating a correction current; and a color purity correction coil 2 formed at an upper and lower position perpendicular to the tube axis of the neck portion of the CRT 1 and for correcting the color purity of an image by the color purity correction current.
It is composed of

As shown in FIG. 2, the coil 2a and the coil 2b are formed as a set of upper and lower color purity correction coils in a plane perpendicular to the tube axis of the neck of the CRT 1, as shown in FIG.
Consists of

Next, a CRT according to an embodiment of the present invention will be described.
The operation of the display device will be described with reference to the drawings.

As shown in FIG. 1, the operation of the CRT display device according to the embodiment of the present invention is as follows. The temperature around the CRT 1 and the hue and brightness of the image signal displayed on the CRT 1 are detected by the detecting element 3. The control circuit 5 compares the detected parameters with the parameters at the time of adjusting the CRT 1 stored in the storage circuit 4 to calculate a change in color purity. From the color purity correction amount when the unit current is supplied to the color purity correction coil 2 and the horizontal and vertical synchronization signals stored in the color purity correction coil 2.
The drive circuit 6 supplies a current to the color purity correction coil 2 based on the calculated result, and the current flows in the horizontal direction in the display screen as shown in FIG. Correct color purity.

[0014]

As described above, according to the CRT display device of the present invention, the temperature around the CRT and the change in the hue and brightness of the image signal displayed on the CRT are automatically detected by the detecting element. This detection value and the value of the parameter stored in the storage circuit are compared and calculated by the control circuit, and a current proportional to the magnitude of the comparison is passed by the drive circuit to the color purity correction coil to correct the color purity. When the temperature is set under an extreme temperature change from the temperature at the time of the adjustment, there is an effect of reducing the influence of the doming of the shadow mask and the deterioration of the color purity and the uneven color due to the variation of the product.

[Brief description of the drawings]

FIG. 1 is a block diagram of a CRT display device according to an embodiment of the present invention.

FIG. 2 is an external view of a color purity correction coil of the CRT display device according to one embodiment of the present invention.

FIG. 3 is an explanatory diagram of a color purity correction direction during operation of the CRT display device according to one embodiment of the present invention.

FIG. 4 is an external view showing a color purity correcting bipolar magnet of a conventional CRT display device.

FIG. 5 is a CRT structure diagram of a conventional CRT display device.

FIG. 6 is an explanatory diagram of a color purity correction direction of a conventional CRT display device.

[Explanation of symbols]

 1,201 CRT 2,2a, 2b Color purity correction coil 3 Detector 4 Storage circuit 5 Control circuit 6 Drive circuit

Claims (1)

[Claims] 1. A CRT, a detecting element for detecting a color and brightness of an image displayed on the CRT, and detecting a temperature around the CRT, and a detecting element for detecting a temperature around the CRT detected by the detecting element. A storage circuit in which the color and brightness parameters of the image are stored in advance in association with the temperature, and the CR is stored based on the parameters stored in the storage circuit.
A control circuit for calculating a color purity correction current value from the hue and brightness of the image displayed on T; a drive circuit for generating a color purity correction current from the color purity correction current value calculated by the control circuit; A color purity correction coil formed at an upper and lower position perpendicular to the tube axis of the neck portion and for correcting the color purity of the image by the color purity correction current.