JPH0813149B2 - Static Convergence Adjuster - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a static convergence adjustment device capable of automatically and quickly and accurately adjusting the static convergence of a projection type color image receiver.

2. Description of the Related Art In a projection type color image receiving apparatus that magnifies and projects on a screen by using three picture tubes emitting three primary colors, the incident angle of the picture tube to the screen is different for each picture tube, and thus the color shift occurs on the screen. Occurs. The so-called convergence of superimposing these three primary colors is performed by making a correction waveform synchronized with the horizontal and vertical scanning periods and adjusting this waveform.

Adjustment of static convergence in the projection type color tube will be described with reference to FIGS. 3 and 4.

First, when a synchronizing signal is applied to the terminal 15 shown in FIG. 3, the control circuit 16 and the correction pattern generation circuit 17 display a correction pattern (cross hatch) on the screen as shown in FIG.
The intersection of the central grids of the correction pattern is set as the static convergence adjustment point 21.

By visually observing the state of color superimposition of the three primary colors at this adjustment point, the bipolar DC current flowing through the static convergence coil 20 can be varied by the DC control circuit 19 by the key operation of the control panel 18 shown in FIG. To set the static convergence optimally.

The problem to be solved by the invention is that in such a conventional device, the adjuster visually adjusts the convergence, so that the adjustment work is troublesome and the workability is poor, and the adjustment state is also poor in accuracy. It had the drawback of not being homogeneous.

In view of the above problems, it is an object of the present invention to provide a convergence device capable of automating static convergence adjustment.

Means for Solving Problems The static convergence automatic adjustment device of the present invention has two locations in an overscan area of a normal convergence adjustment pattern (such as a crosshatch) (two locations on the left and above the circumscribed area of the effective screen area). A static convergence automatic adjustment auxiliary pattern is superimposed on the image sensor, and an image sensor that receives color misregistration information of the auxiliary pattern is provided at two locations (positions corresponding to the auxiliary pattern) near the circumscribed area of the image receiving effective area of the screen body. The transferred color misregistration amount is calculated, and the convergence correction waveform corresponding to the calculation result is input to the static convergence coil.

Effect The present invention enables automatic adjustment of static convergence by the above-described configuration, and in addition, eliminates a difference factor of setting by an adjuster, and enables highly accurate and uniform convergence.

Example Hereinafter, an example of the present invention will be described with reference to FIGS. 1 and 2.

FIG. 2 shows a static convergence adjustment pattern according to an embodiment of the present invention, in which an auxiliary pattern is superposed on two places (upper and left) of an overscan area of a normal screen. Figure 2a
Shows the relationship between the arrangement of the image sensor and the auxiliary pattern. The image sensor for receiving the positional information of the auxiliary pattern is arranged so as to be orthogonal to the auxiliary pattern as shown in FIG. 2b.

Next, a method of detecting the auxiliary pattern position will be described. On the image sensor, as shown in FIG. 2A, the luminance distribution of the monochrome auxiliary pattern for the image sensor is detected. The peak of the luminance distribution is detected to find the address of the pattern position.

From the calculation of the color shift amount to the convergence adjustment will be described with reference to the block diagram of FIG.

When a sync signal is applied to the sync signal input terminal 1 of FIG. 1, the control circuit 2 and the correction pattern generating circuit 3 cause the correction pattern to be displayed on the upper and left sides of the circumscribed area of the screen effective area as shown in FIG. It is projected on the place. At first, the control CPU 5 and the color switching circuit 4 display a green single color raster.

As shown in FIG. 2b, the first and second image sensors 6 and 7 are arranged so as to be orthogonal to the auxiliary pattern, and the position of the auxiliary pattern is detected by the luminance distribution of the input light to the image sensor. It is obtained from the peak detection of.

The position address of the green pattern in the x and y directions obtained by the first image sensor 6 and the second image sensor 7 and the pattern position detection circuit 8 is stored in the pattern position address memory 9. When the storage of the position address of the green pattern is completed, the control CPU 5 and the color switching circuit 6 switch from the green single color raster to the red single color raster, and like the case of the green pattern, the position address of the red pattern is stored in the pattern position address memory. 9 is stored. When the storage of the position address information of the red pattern is completed, the position address information of the green and red patterns is transferred to the difference circuit 10, and the correction amount is calculated from the color shift amount of the red pattern with respect to the green pattern. Memorized in. Further, the correction amount data is converted into an analog signal by the D / A conversion circuit 12, smoothed by the low pass filter (LPF) 13, and supplied to the convergence coil after widening, so that static convergence correction can be performed on the screen. Done.

Next, after correction, the above procedure is repeated again, and when the minimum feedback amount is determined by the feedback determination circuit 14, the above procedure is terminated.

 The blue pattern is similar to the red pattern.

As described above, the automatic adjustment of the static convergence of the three primary colors is completed.

EFFECTS OF THE INVENTION As described above, according to the present invention, it is possible to automate the adjustment of static convergence, and thereby it is possible to perform highly accurate and uniform adjustment.

[Brief description of drawings]

FIG. 1 is a block diagram of a static convergence adjusting device according to an embodiment of the present invention, FIG. 2 is a schematic explanatory diagram thereof, FIG. 3 is a block diagram of a static convergence adjusting device of a conventional example, and FIG. 4 is a conventional example. It is a correction pattern diagram for convergence adjustment. 1 ... Sync signal input terminal, 2 ... Control circuit, 3 ... Auxiliary pattern generation circuit, 4 ... Color switching circuit, 5 ... Control CP
U, 6 ... First image sensor, 7 ... Second image sensor, 8 ... Pattern position detection circuit, 9 ... Pattern position detection circuit, 10 ... Difference circuit, 11 ... One frame memory, 12 …… D / A conversion circuit, 13 …… LPF.

Claims (1)

[Claims] 1. A device for generating an auxiliary pattern of RGB three primary colors which is linearly emitted outside a display effective area on a center line of a vertical axis and a horizontal axis of a display screen in a projection color receiver, and A color switching circuit for displaying one of the auxiliary patterns of the three primary colors of RGB, a brightness distribution detecting device for detecting the brightness distribution of the auxiliary pattern by using an image sensor orthogonal to the auxiliary pattern, and the brightness distribution detecting device. By calculating the maximum value from the luminance distribution transferred from the above, the misconvergence amount is arithmetically processed and fed back to the static convergence adjustment circuit to automatically perform the optimum setting of the static convergence state. Characteristic static convergence adjustment device.