JPH02294185A - Screen structure in projection tv - Google Patents

Abstract

PURPOSE:To automatize convergence adjustment by forming a recessed part on the incident plane of a lenticular lens, arranging a photodetector so as to position at the extension of the recessed part at an surface, and setting the output of the photodetector as adjustment control information. CONSTITUTION:When the incident plane of the lenticular lens 5 is irradiated with light by performing horizontal and vertical scan, incident light on a notch 6a or 6b enters the inside of the lenticular lens 5, and is propagated to the inside of the lenticular lens 5 in a ridge direction (vertical scan direction), and is made incident on the photodetectors 7a and 7b arranged at a lower end. The output signals of the photodetectors 7a and 7b are waveform-arranged to pulse signals with waveform arranging circuits 8a and 8b, and are supplied to a system controller 9 as control information for the convergence adjustment. Thereby, the convergence adjustment can be performed without affecting on a video on a screen, and the convergence adjustment can be automatized.

Description

TECHNICAL FIELD The present invention relates to a screen structure in a projection TV, and more particularly to a screen structure including a lenticinary lens in a projection TV equipped with an automatic convergence adjustment circuit.

Background technology In projection TV, R (red), G (green),
Because the B (blue) projection tubes are arranged in the horizontal scanning direction, the projection angle of each tube is different, so the images projected by each tube on the screen are inevitably different.
This will result in color shift. In order to correct this color shift, the projection TV is provided with a convergence adjustment circuit.

This convergence adjustment circuit is configured to perform correction by flowing current corresponding to color shift to each horizontal (H) and vertical (V) sub-deflection yoke provided for convergence adjustment. . Conventionally, in this convergence adjustment circuit, the adjuster corrects color shift by checking the raster distortion pattern while looking at the screen and adjusting the current supplied to the sub-deflection yoke by adjusting the volume. was common.

However, when the convergence adjustment is performed manually, the adjustment skill level and visual ability differ depending on the person, resulting in variations in the convergence adjustment. Therefore, it is preferable to be able to perform convergence adjustment automatically.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a screen structure for a projection TV that can contribute to automation of convergence adjustment.

In the screen structure according to the present invention, the screen includes a lenticular lens, and the screen is a projection TV equipped with an automatic convergence adjustment circuit.
At least 1l of the entrance surface of the lenticular lens! ! A recess is formed in the lenticular lens, and a light receiving element is arranged on the end face of this lenticular lens so as to be located on an extension line of the recess in the vertical or horizontal scanning direction, and the output of this light receiving element is used as adjustment control information of an automatic convergence adjustment circuit. It is configured to be used as a

Example Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 is a block diagram showing an automatic convergence adjustment system in a projection TV with a screen structure according to the present invention. In the figure, 1 is RG-
This is a projection TV set consisting of three projection tubes (not shown) in B, and although it is shown as an external circuit in the drawing, color shift correction is performed as part of the internal circuit within the set. A convergence adjustment circuit 2 for driving and a color signal output circuit 3 for driving each RGB projection tube are built in.

In this Proziexigine TV set 1, the screen 4 has a lenticular lens 5 shaped as shown in FIG.
Contains. This lenticular lens 5 is arranged so that the wavy surface becomes the incident surface and the ridgeline direction becomes the vertical scanning direction, and at least one location on the incident surface, for example, two locations indicated by X marks on the screen 4 in FIG. Notches (notches) 6a and 6b are formed in four parts. Further, on the lower (or upper) end surface of the lenticular lens 5, a notch 6a, located on an extension line of the notches 6a, 6b in the vertical or horizontal scanning direction.
For example, two light receiving elements 7g and 7b are arranged corresponding to the number of light receiving elements 6b.

In this screen structure, when the incident surface of the lenticular lens 5 is irradiated with light by horizontal and vertical scanning, the light incident on the notches 6a and 6b enters the inside of the lenticular lens 5, and the lenticular lens 5
For example, as shown in FIG. 3, the light propagates in the ridge line direction (vertical scanning direction), reaches the upper and lower ends of the lenticular lens 5, and enters the light receiving elements 7a and 7b arranged at the lower end of the lenticular lens 5. Light receiving element 7a. The output signal 7b is waveform-shaped into a pulse signal by waveform shaping circuits 8a and 8b, and is supplied to the system controller 9 as control information for convergence adjustment, which will be described later.

Note that the recess formed on the entrance surface of the lenticular lens 5 is not limited to a notch (notch), but may be a conical recess, for example, and in the case of a four conical recess, the incident light is In order to propagate inside the lenticular lens 5 not only in the vertical scanning direction but also in the horizontal scanning direction, the light receiving elements 7a and 7b may be arranged not at the upper and lower end surfaces of the lenticular lens 5 but at the left and right ends.

The system controller 9 is constituted by, for example, a microcomputer, and during convergence adjustment, its processor executes the processing described below in accordance with the procedure shown in the flowchart of FIG. 4. That is, in response to power-on of the system, for example, the processor first switches the output of the color signal output circuit 3 to drive the G projection tube to project green onto the screen 4 (step S1), and the light receiving element 7a. , 7b is monitored (step S2). Then, the light receiving elements 7a . 7b is held as time axis data in the vertical and horizontal directions based on the vertical (V) synchronization signal and horizontal (H) synchronization signal obtained by the synchronization separation circuit 10 (step 83).

Next, for example, drive the R projection tube to project red on the screen 4 (step S4), and use the same procedure as in the case of G to determine the vertical and horizontal timings of each of the light receiving elements 7a and 7b in the case of R. Obtain time axis data in the direction (steps S5 and S6). Then, find the difference between the time axis data of R and the time axis data of G at each point indicated by the X mark on the screen 4 in FIG.
It is held as the color shift amount of R for (step 87)
.

Furthermore, by the same procedure as in the case of R, G at each point is
The amount of color shift of B relative to the time difference data is determined and held as time difference data (steps 88 to S11).

After determining the amount of color shift at each point of R and B with respect to G as time difference data, the processor then corrects the color shift by driving and controlling the convergence adjustment circuit 2 based on these time difference data (step S12). ).

The convergence adjustment circuit 2 is a waveform generator that generates various analog waveforms such as a V/H sawtooth wave and a V/H parabolic wave for correcting several types of raster distortion patterns, as shown in FIG. circuit 21, VR circuits 22H, 22V which are made up of variable resistor (VR) arrays connected in parallel and adjust the level of each waveform signal, and matrix amplifier 23H.22V which mixes each waveform signal after level adjustment.
23■, and each H-V sub-deflection yoke 25H. It is composed of drive amplifiers 24H and 24V that drive 25V, and the VR circuit 2 is controlled by the system controller 9.
2H. By adjusting each resistance value of 22V, the current flowing through each sub-deflection yoke 25H and 25V changes, thereby correcting color shift.

Note that the convergence adjustment circuit 2 is not limited to the configuration shown in FIG. 5, but can be of various configurations, and it is also possible to adopt a digital convergence adjustment method, as an example. , the correction waveform data itself can be generated by a microcomputer and the convergence adjustment can be performed by changing the waveform itself.

Further, in the above embodiment, the convergence adjustment is performed when the power of the system is turned on, but the present invention is not limited to this, and it may be performed at any time determined by the user or automatically. Furthermore, the formation position and number of notches and the corresponding number of light receiving elements are arbitrary, and the larger the number, the better the convergence adjustment can be performed.

Effects of the Invention As explained above, in the screen structure according to the present invention, in a projection TV equipped with an automatic convergence adjustment circuit, a concave portion is formed in at least one place on the incident surface of the lenticular lens, and a concave portion is formed in the end surface of the lenticular lens. The light-receiving element is arranged so as to be located on the extension line of the four parts in the vertical or horizontal scanning direction, and the output of this light-receiving element is used as adjustment control information for the automatic convergence adjustment circuit. This makes it possible to adjust convergence without adversely affecting images, contributing to the automation of convergence adjustment.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an automatic convergence adjustment system for a projection TV equipped with a screen structure according to the present invention, FIG. 2 is a perspective view showing main parts of the screen structure according to the present invention, and FIG. longitudinal section,
FIG. 4 is a flowchart showing a convergence processing procedure, and FIG. 5 is a circuit diagram showing an example of a convergence adjustment circuit. Explanation of symbols of main parts 1...Projection TV set 2...
... Convergence: A rectifier circuit 4 ... Screen 5 ... Lenticular lens 6a. 6b... Notches 7a, 7b... Light receiving element 9... System controller

Claims (1)

[Claims] A screen structure including a lenticular lens in a projection TV equipped with an automatic convergence adjustment circuit, wherein the lenticular lens has at least one of its incident surfaces.
A light receiving element is provided on the end face of the lenticular lens so as to have a recessed part in the vertical or horizontal scanning direction so as to be located on an extension line of the recessed part, and the output of the light receiving element is connected to the automatic convergence adjustment circuit. 1. A screen structure in a projection TV, characterized in that it is used as adjustment control information for a projection TV.