JPH038239A - Method and device for adjusting image plane inclination of display tube - Google Patents

Abstract

PURPOSE:To perform the high-grade horizontal deflection adjustment of a high- precision display tube including a general display tube by monitoring a horizontal line and vertical side markers displayed on the display tube, and comparing respective high-precision intensity centers of gravity. CONSTITUTION:A horizontal line display 7 is displayed by horizontal scanning to adjust a display tube 1, and side markers 5 and 6 provided at the vertical center section on both ends of an image plane are pulled together and luminescence-displayed via solenoid coils 10 and 11 by the raster signal or as required. The display tube 1 is monitored by two ITV cameras 14 and 17, and the signals are inputted to a video memory 19. The intensity center of gravity of a pattern on the display tube 1 adds intensity in the horizontal X-axis direction for each vertical axis Y-coordinate, and the phosphor dot size is precisely calculated. Deflection adjustment is performed so that the intensity center of gravity of the horizontal line display 7 is made parallel with a virtual line 29 connecting intensity centers of gravity of the side markers 5 and 6.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method and device for adjusting the screen tilt of a display tube in a display device such as a character display device.

[Conventional technology]

In various display devices using cathode ray tubes, a two-dimensional screen display is obtained by deflecting and scanning an electron beam from an electron gun horizontally and vertically using a deflection yoke.

The deflection yoke is installed at the neck of the cathode ray tube, and the mounting position must be adjusted so that the screen formed by the deflection scan is accurately aligned horizontally and vertically.

As a conventional adjustment technique of this kind, the Japanese Patent Publication No. 58-218
As described in Publication No. 68, a horizontal line pattern is displayed on the cathode ray tube to be inspected, this display is imaged with a television camera whose scanning direction is rotated 90 degrees so that the horizontal scanning lines are vertical, and the imaged signal is It is known to calculate the amount of deviation between the peak value at two points and the virtual horizontal reference line, and adjust the deflection yoke position based on this amount of deviation.

(Problems to be Solved by the Invention) The above-mentioned conventional technology is aimed at general television picture tubes (television cathode ray tubes), and is applicable to character display tubes (CDTs) and monitor tubes (hereinafter referred to as CDTs). It is difficult to apply it to high-definition display tubes such as

In other words, with CDT, there is a method in which a minute side marker is provided at the center of the vertical side of the CDT screen, and the screen tilt is adjusted using this side marker as a horizontal scanning line reference mark, but with underscan CDT, the side marker in the screen is Since there is a non-light-emitting area in the side marker, it is difficult to perform fine print adjustment based on the side marker.

In the conventional method of adjusting the screen around 1, the optical resolution is insufficient to detect the minute side marker, and it is impossible to perform accurate adjustment.

Further, there is a problem in that it is impossible to adjust with high precision (for example, 0.5 n+) for the variation in horizontality (about 1.6 n) of the CDT itself.

It is an object of the present invention to solve the problems of the prior art described above, and to enable high-precision horizontal/vertical adjustment of display tube screens even in CDTs, which are high-definition display tubes, as well as general display tubes. An object of the present invention is to provide a tilt adjustment method and device.

[Means to solve the problem]

The above purpose is to use an ITV camera to photograph side markers and horizontal line patterns emitted by raster signals for overscan type display tubes, and to photograph raster signals on the side of the screen for CDT screens, which are underscan type display tubes. direction(
The screen is overscanned in the horizontal direction (horizontal direction) to emit fluorescent dots that serve as side markers, and this screen is captured by a television camera (r
(TV camera), monitor the image signal, store it in the video memory, freeze it at 512 degrees horizontal pixel and 480 vertical pixels, and mark the widthwise center and both side markers of the displayed horizontal line pattern. This is achieved by rotating and adjusting the deflection yoke so that the connecting lines are parallel.

[Effect]

The CDT screen will be monitored by two ITV cameras.

For example, the camera has a 50 mm lens and a 2511 extension tube to enlarge and photograph the screen.
Side markers of about 100 μΦ provided at the left and right ends of a horizontal line horizontally across the center of the screen and on the vertical sides of the CDT are monitored.

At this time, in the case of an underscan type CDT, the raster does not reach the position where the side marker is ordered, so
The blanking period within one horizontal scanning period of the horizontal synchronization signal of the programmable raster signal, that is, the front porch and back porch are significantly deflected and the raster signal is swung horizontally to move the phosphor dots that serve as side markers to the left and right. The lights are emitted alternately and this is photographed with an ITV camera. If the overscan is insufficient, an electromagnetic means such as a solenoid coil is provided on the side of the display tube to attract the raster signal and cause the side marker phosphor to emit light.

By this photographing, the positions of both side markers are frozen in memory. After that, the screen of the horizontal line pattern displayed on the CDT is photographed, the signal of the photographed horizontal line is stored in the memory, and the deflection yoke is adjusted so that the horizontal position of the horizontal line and the left and right side markers are aligned or parallel. Rotate.

〔Example〕

Embodiments of the invention will now be described with reference to a brief description of the drawings.

FIG. 1 is a configuration diagram illustrating a positional embodiment of the present invention, in which 1 is a CDT, 2 is a deflection yoke, 3 is a neck portion of a CRT, 4 is a correction magnet, and 5.6 is a vertical center side marker (hereinafter referred to as , side marker), 7 is horizontal line display (hereinafter referred to as horizontal line), 8.9 is monitor area, 10.11 is solenoid coil, 12 is 50m lens, 13.16 is 25 crane close-up ring, 14.17 is ITV 18 is a camera selector, 19 is a video memory (image memo U), and 20 is a monitor.

In the figure, a horizontal line pattern 7 is displayed at the side marker 5.6 position on the CDTl screen. This horizontal line pattern can be displayed by horizontally scanning an electron beam from an electron gun (not shown) using the deflection yoke 2 and the correction magnet 4.

In the case of an underscan type CDT, the blanking period of the horizontal synchronization signal of the programmable signal for supplying the raster signal to the CDT is changed for each horizontal scan, so that the raster causes the side markers 5.6 to emit light alternately. Make it. The side markers 5.6 are formed of phosphor dots of about 100 μΦ, and the ITV cameras 14 and 17 take an enlarged photograph of the light emitted by the phosphor dots when the electron beam strikes them.

The photographing signals of the cameras 14 and 17 are alternately written to the video memory 19 by the camera selector 18, and are simultaneously written to the monitor 20.
supplied to

FIG. 2 is a schematic diagram showing the monitor image of the monitor 20 in FIG. 1, in which 21 is a fluorescent dot, 22 is a non-light emitting area, 23 is a side marker area, and 24 is a raster signal.

It shows the monitor area 9 of FIG. 1, and displays the horizontal line 7 and the side marker 6 at the same time.

In the same figure (a), underscan type CDTl
There is a non-light-emitting portion 22 on the screen, and the side marker 6 located in a region 23 outside this portion does not emit light.

The same figure (b) shows the raster signal 24 and the side marker fluorescent dot 6, and by swinging this raster signal 24 to the area of the side marker position 6, as shown in the same figure (c), the side marker The phosphor dots can be made to emit light.

FIG. 3 is a schematic diagram of monitor images for explaining the operation of this embodiment, in which (a) is the monitor area 8 photographed by the ITV camera 14 in FIG. 1, and (b) is the ITV camera I7 in FIG. The monitor area 9 photographed in (c) is an overall view of the screen.

In the same figure, the horizontal inclination is calculated based on the positional relationship between the horizontal line signal 7 (□) and the side marker 5.6, and the rotational direction position of the deflection yoke 2 is adjusted based on the calculation result to align the horizontal line 29 with the horizontal line. The horizontal line pattern emitted by the line signal 7 is arranged in a parallel relationship.

In (a) and (b), which are enlarged views of the monitor area, the light-emitting phosphors 21 in a horizontal line pattern are lined up in the horizontal direction along the horizontal line, and the phosphors above and below this horizontal line are non-emissive and dark. .

The center of the luminescent width of the phosphor that displays a horizontal line pattern is set to Yvg9. When Ygv3 is set, if the pattern 7 passes the side markers 5 and 6, the screen tilt adjustment is completed.

Even if the horizontal line 7 is slightly shifted up and down on the screen, it suffices if the center line connecting its left and right ends is parallel to the imaginary straight line 29 connecting the left and right side markers 5.6.

FIG. 4 is an explanatory diagram of an algorithm for finding the horizontal center of a horizontal line. As mentioned above, for example, in the monitor area 8 of (a), an underscanned white scanning raster as shown in (b) is displayed on this monitor. By swinging the area to the left, the side marker 5 also lights up, the non-light-emitting area 22 also lights up, the ITV camera 14 takes an enlarged picture, and the video memory 19 stores the horizontal pixels 5I2, . Freezes at vertical pixel 4801 gradation 256.

Next, the raster signal is switched to a horizontal line signal, which is photographed and frozen in the video memory 19.

Find the center of the horizontal line pattern at this time. Note that the fluorescent dot corresponds to the pixel address number 10'' of the video memory 19.

In the same figure (C), point 35-3 forms a horizontal rectangle.
When 6-37-38 are connected, the upper edge line is 39 degrees, and the lower edge line is 40 degrees. When finding the center 27 of the horizontal line 7, instead of simply finding the Y-axis pixel coordinate YVg27, A rectangle is extracted and determined as described below with reference to FIG.

FIG. 5 is a detailed explanatory diagram of an algorithm for finding the center of a horizontal line (center of gravity of data).

Horizontal - &? The calculation of the center of I7 adds the luminescence density (brightness) in the X-axis direction for each Y-axis coordinate, and projects the luminescence density. If this is expressed as a density (brightness) distribution m33 of the projection 34, the projection value of the X axis of the Y0 coordinate is 41.
Yl coordinate X-axis projection value 42, Y7 X-axis projection value 43
is determined by the following formula.

Ya m=m, , +m, 6+ --Y, m=m
,,+m,,+ −・+mIIo=ΣmX.

2゜ + mA + = Σmx.

Y, m=m6. +m, , + −−+m, 11I=Σm0
However, O<X<512 This is taken as the drawing distribution characteristic 34 from Ya to Y7, and its central distribution pixel address Yvg27 is determined. Its general formula is shown in the following formulas (1) and (2).

Y, m-Σm ・ ・ ・(1
) Ya m − (Σm) ÷ (x, −Xo)
...(2) In addition, the video memo January 9 in Figure 5
The luminescence density of pixel address 35 (xo, yo) of
It is set as oo.

As described above, the light emission center of horizontal line pattern 7 (center of brightness distribution), the light emission center of side marker 5.6 (center of brightness distribution)
Calculate pixel address.

According to the algorithm described above, the rotational position of the deflection yoke is adjusted so that the Y-axis pixel address of the side marker and the pixel address of the horizontal line pattern are the same, and the screen inclination is adjusted.

FIG. 6 is a block diagram illustrating the detailed configuration of one embodiment of the display tube screen tilt adjustment device according to the present invention.

In the same figure, the tube surface (screen) of the CDTl formed by the Larta signal supplied from the signal generator 65 is
Enlarge the image with TV camera 14.17 and press camera selector 1.
8, the left marker area 8 and right marker area 9 of the screen are alternately selected and their image signals are frozen in a video memory (video image memory) 19. The frozen image data is monitored on a monitor 20.

The CPU 52 transfers the data in the video memory 19 to the parallel data line 49 and the handshake interface (Ilo).
50, the algorithm is controlled and calculated in the ROM 53 which stores the program of the algorithm, and the calculation result is stored in the RAM 54. In addition, r
Reference numeral 1055 is an interface that provides a camera selection signal for selecting either the camera 14 or the camera 17 to the camera selector 18.

In addition, l1056 is the position adjustment data (3) of the deflection yoke 2.
The CTL 72 generates a rotation signal for the deflection yoke 2 as a drive pulse number signal from the data loaded from the CPU 52 and applies it to the motor driver 70. The control line 74 gives a work start signal 5tart, clockwise cty, and counterclockwise command signals to the CTL 72, and transmits a work end signal END to the CPU 52 as an answer.

The motor 69, which is a stepping motor, rotates in a direction instructed by a drive signal from the motor driver 70, and the deflection yoke rotation mechanism 89 rotates the deflection yoke 2.

The I10 interface 57 provides arbitrary pattern signals and timing signals from the CPU 52 to the signal generator 65, and the signal generator 65 connects red, green, and blue signal lines 66.
．． 67 and 68 to supply signals necessary for adjustment to the CDT.

11058 has D/A converters 59. An excitation current is passed through the current driver 60, the electromagnetic magnet 64 is operated according to the camera selection, and the solenoid switches 61, 62, and 63 are controlled to trigger the raster signal described above.

The means for causing the side marker to emit light will be explained below.

FIG. 7 is an explanatory diagram of a first means for causing a side marker to emit light by changing a raster signal, and FIG.
As shown in , the standard raster signal has one horizontal scanning period (LH
) 80, horizontal synchronization signal 76, front porch 77, video period 78. Holds bank pouch 79 and video period 78 is C
It is located in the effective display area 24 of the DTl screen. In this underscan type display device, the side marker is 5.6
A non-light emitting area 22 exists between the display area 24 and the side marker 5.6, and the side marker 5.6 does not emit light with this raster signal. Therefore, as shown in (b) and (c) of the same figure, the raster signal that scans the left side of the display screen deletes the front porch of its horizontal blanking period, and the raster signal that scans the right side deletes its back porch. The side marker 5.6 is caused to emit light by deleting the signal and setting the signal at the same level as, for example, the white signal in the video period.

Note that the horizontal synchronization signal 76 and the IH period 80 are fixed.

FIG. 8 is an explanatory diagram of a second means for attracting raster signals to the horizontal end of the screen, and as shown in FIG. 8(a), solenoid coils 10.
11, an excitation current is applied to these coils, and the raster signal is attracted to the position of the side marker 5.6 and caused to swing, thereby causing the side marker 5.6 to emit light.

FIG. 5B is an explanatory diagram when the left side marker 5 of the CDT 1 is made to emit light, and the terminal 81 of the solenoid coil 10
．． When a left excitation current (iL) 85L is applied to the raster 82, the raster 24 covers the area 8 and is attracted to the left as shown, and the side marker 5 also emits light.

Also on the right side of the screen, as shown in the same figure (e), the right excitation current (i
R) By flowing 85-R, the right side area 9 is covered and the raster 24 causes the side marker 6 to emit light.

The left and right excitation currents can have waveforms as shown in FIG. 1D, and the raster is attracted by the electric current 1i 85, and then the alternating attenuation current 86 is passed to demagnetize the shadow mask and the like.

Such adjustment is generally performed after adjusting the horizontal center of the CDT to be adjusted.

〔Effect of the invention〕

As explained above, according to the present invention, not only an overscan display tube but also an underscan display tube can be used.
The side markers also emit light on the DT, and this is used on the ITV.
The straight line connecting the side markers photographed with the camera and frozen in memory coincides with or is parallel to the luminance centroid line obtained by calculating the luminance distribution data of a horizontal line pattern based on the raster signal photographed with the ITV camera. Since the position of the deflection yoke in the rotational direction is adjusted as shown in FIG. Methods and apparatus can be provided.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram explaining a positional embodiment of the present invention, FIG. 2 is a schematic diagram showing a monitor image of the monitor 20 in FIG. 1, and FIG. 3 is a monitor image explaining the operation of this embodiment. Figure 4 is an explanatory diagram of the algorithm for finding the horizontal center of a horizontal line, Figure 5 is the center of the horizontal line (center of gravity of data)
6 is a block diagram illustrating the detailed configuration of an embodiment of the display tube screen tilt adjustment device according to the present invention, and FIG. FIG. 8 is an explanatory diagram of the first means for causing the marker to emit light, and FIG. 8 is an explanatory diagram of the second means for attracting the raster signal to the edge side in the horizontal direction of the screen. 1... CDT, 2... Deflection yoke, 3...
CDT neck section, 4...Correction magnet, 5.6
...Vertical center side marker (side marker), 7.
... ・Horizontal line pattern, 8.9... Monitor area, 10.11 ... Solenoid coil, 12...
... Lens, 13.16 ... Close-up ring, 14
．． 17...ITV camera, 18...camera selector, 19...video memory (image memory),
20...Monitor. Figure/:CDT 2, Iitakouyofu/Q, //:'Noshi Noetoko de Lu I4. Noah + ITV camera 8 18.77 Nura tL Kuta I9: 2 T"f Me'tj1 20: tNita Fig. 2 (a) and b (b) 6 (C) (C) Fig. 4 (O) ( b) χnyO χn, χy Q + 楕＼ Approved Figure 7 (a)

Claims (1)

[Scope of Claims] 1. A method for adjusting the screen tilt of a display tube, which displays a horizontal line light emission pattern on the screen of the display tube, and adjusts the tilt of the display screen by monitoring the horizontal line light emission pattern.
By applying a raster signal to both left and right ends of the screen of the display tube in the horizontal direction, vertical side markers provided at both ends of the screen are made to emit light, and the left and right areas of the horizontal line light emission pattern including the side markers are illuminated. Determine the center of gravity of the vertical luminescence amount of the image signal obtained by enlarging each image,
A method for adjusting the screen tilt of a display tube, comprising adjusting the position in the rotational direction of a deflection yoke of the display tube so that the straight line connecting the obtained left and right centers of gravity is parallel to an imaginary horizontal line. 2. In a display tube screen tilt adjustment device that displays a horizontal line emission pattern on the display tube screen and adjusts the display screen tilt by monitoring this horizontal line emission pattern,
A horizontal line pattern generation means for displaying a horizontal line emission pattern in the center of the screen of the display tube, and a raster signal for generating the pattern provided at both ends of the screen by distributing it to both left and right ends in the horizontal direction of the screen of the display tube. a side marker light emitting means for emitting light from a vertical side marker; a photographing means for respectively enlarging left and right regions of the horizontal line pattern including the side markers; A calculation means for calculating the center of gravity of the light emission amount at the end, and adjusting the rotational direction position of the deflection yoke of the display tube so that a straight line connecting the center of gravity of both left and right ends obtained by this calculation means is parallel to an imaginary vertical line. 1. A screen tilt adjustment device for a display tube, comprising a deflection yoke adjustment means.