JPS6246118B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a color cathode ray tube convergence measuring device that measures and displays the amount of misconvergence without relying on visual measurement.

A microscope is generally used to measure the misconvergence of conventional color cathode ray tubes. For example, when calculating the misconvergence of blue (B) with respect to green (G), as shown in Figure 1, the left edge deviation Lbg
The center axis deviation Cbg is obtained from the arithmetic mean of the deviation Rbg (-2 stripes) and the right edge deviation Rbg (+4 stripes). That is, Cbg=Lbg+Rbg/2=-2+4/2=1 stripe In this way, if the stripe width is known, the misconvergence amount Cbg can be determined as a specific length.

However, conventional color cathode ray tube convergence measurements (A) require numerical calculations during the measurement, making the procedure cumbersome and prone to calculation errors and reading errors; (B) measurement takes time; (C) There were drawbacks such as high fatigue for the person taking the measurements.

Therefore, an object of the present invention is to provide a convergence measuring device that can automatically display the amount of misconvergence on a display.

In order to achieve such an object, the present invention provides a means for extracting a desired bright line on the screen of a color cathode ray tube, and a light receiver that converts the left and right lights of the bright line, respectively, into electric signals with the optical axis of the bright line as the center. ,
an amplifier that differentially amplifies the electrical signal output from the light receiver; an indicator to which the output signal of the amplifier is input; a moving means for moving the light receiver in the misconvergence direction; and a movement amount of the light receiver. The device is equipped with a display device that measures the amount of misconvergence and displays the amount of misconvergence, and will be described in detail below using examples.

FIG. 2 is a configuration diagram showing an embodiment of the convergence measuring device according to the present invention. In the same figure, 1
2 is a color cathode ray tube; 3 is a base; 4 is a filter assembly including a red filter, a blue filter, and a green filter, each of which is supported on the base 3 so as to be extendable; 5, a cathode ray tube 2; The left photovoltaic element 5a and the optical axis are set on the vertical lines, that is, the bright lines, of the crosshatch pattern projected on the fluorescent light surface of the photovoltaic device, and convert the light on the left side from the optical axis into an electrical signal, as shown in FIG. A light receiver 6 consisting of a right photovoltaic element 5b that converts light from the right side into an electric signal is movably attached to the base 3,
A microhead with a light receiver 4 fixed to one end; 7 a linear encoder that detects the amount of movement of the light receiver 5 with respect to the base 3 and outputs a signal of the movement; 8 an output signal of the left photovoltaic element 5a and a right side photovoltaic element 5a; a differential amplifier 9 to which the output signal of the photovoltaic element 5b is input;
1 is an indicator to which the output signal of the differential amplifier 8 is input; 10 is a display that displays the output signal of the linear encoder 7; 11 is a controller; 12 is a controller that operates the controller 11 to advance the output state one step at a time. This is an operation switch for sequentially bringing out the red filter, blue filter, and green filter of the filter assembly 4 located between the color cathode ray tube 2 and the light receiver 5 onto the optical axis.

Next, the operation of the cosvergence measuring device having the above configuration will be explained.

First, in the vertical lines of the crosshatch pattern projected on the fluorescent surface of the cathode ray tube 2, that is, the enlarged cross section of the bright lines, due to misconvergence, the bright lines of three colors red, green, and blue are shining, and the brightness distribution is
An example of Br, Bg and Bb is shown in Figure 3A. Therefore, in this case, the luminance distribution ir on the left photovoltaic element 5a and the right photovoltaic element 5b of the light receiver 5 is
ig and ib are imaged as shown in FIG. Next, when the red filter, blue filter, and green filter of the filter assembly 4 are sequentially extended onto the optical axis, the luminance distributions ir, ig, and ib on the left photovoltaic element 5a and the right photovoltaic element 5b are Since images are formed for each single color, the brightness distribution ig whose optical axis coincides with the center of the brightness distribution is imaged equally on the left photovoltaic element 5a and the right photovoltaic element 5b. Therefore,
The output signal of the left photovoltaic element 5a and the output signal of the right photovoltaic element 5b have the same magnitude. Therefore, the output of the differential amplifier 8 becomes 0, and the indicator 9 indicates 0.

Next, the operation of measuring and displaying the amount of misconvergence of red and blue with respect to green will be explained.

First, when the operating switch 12 is closed, the controller 11 operates. By this operation of the controller 11, the green filter of the filter assembly 4 is drawn out, and the light receiver 5 enters a state in which it detects the green bright line. Then, the micro head 6 is moved and adjusted so that the indicator 9 indicates 0. next,
When the operation switch 12 is closed, the controller 1
1 is activated, the red filter of the filter assembly 4 is drawn out, the light receiver 5 enters a state to detect the red bright line, and the display 10 is reset.
From this state, so that the indication on the indicator 9 becomes 0,
By moving and adjusting the micro head 6, the display 10
Displays the amount of movement of the light receiver 5, that is, the amount of misconvergence of red with respect to green. Next, when the operating switch 12 is closed, the controller 11 operates. Due to the operation of this controller 11,
The blue filter of the filter assembly 4 is pulled out, and the light receiver 5 is in a state to detect the blue bright line.
From this state, so that the indication on the indicator 9 becomes 0,
When the micro head 6 is moved and adjusted, the display 10 displays the amount of movement of the light receiver 5, that is, the amount of misconvergence of blue with respect to green.

Similarly, by operating the operation switch 12 and using the program of the controller 11, the amount of misconvergence of any fluorescent color can be measured and displayed.

FIG. 4 is a configuration diagram showing another embodiment of the convergence measuring device according to the present invention. In the same figure,
Reference numeral 13 denotes switches 14a to 14c and a drive circuit 1 that closes the switches 14a to 14c, respectively.
This is a cathode switching device consisting of 5a to 15c.

Note that the operation of measuring and displaying the amount of misconvergence is of course similar to that shown in Fig. 2, but in this case, instead of selectively drawing out each filter of the filter assembly 4, the cathode Drive circuits 15a to 15 of switching device 13
c selectively energizes the corresponding switch 14a.
14c, select a predetermined cathode, and measure the amount of misconvergence.

Further, although the reading of the indicator 9 and the driving of the micro head 6 have been performed manually in the above description, it is of course possible to improve the function of the controller 11 and drive the micro head 6 automatically.

As explained above in detail, the convergence measuring instrument according to the present invention does not generate errors caused by the measurer, such as reading errors or calculation errors, and therefore enables highly reliable and highly accurate measurements. can. Furthermore, since measurement can be performed in a short time, measurement efficiency is improved.

[Brief explanation of the drawing]

FIG. 1 is an enlarged view of a fluorescent surface for explaining the conventional measurement of misconvergence amount, FIG. 2 is a block diagram showing an embodiment of a convergence measuring device according to the present invention, and FIGS. FIG. 3B is a diagram showing the relationship between the luminance distribution on the fluorescent surface and the luminance distribution in the light receiver in FIG. 2, and FIG. 4 is a configuration diagram showing another embodiment of the convergence measuring instrument according to the present invention. . 1... Television chassis, 2... Color cathode ray tube, 3... Base, 4... Filter assembly, 5... Light receiver, 5a... Left side photovoltaic element, 5
b... Right side photovoltaic element, 6... Micro head,
7...Linear encoder, 8...Differential amplifier, 9
... Indicator, 10 ... Display, 11 ... Controller, 12 ... Operation switch, 13 ... Cathode switch, 14a-14c ... Switch, 15a-
15c...drive circuit.

Claims (1)

[Claims] 1. A means for selectively extracting red, blue, and green bright lines from a color cathode ray tube, and photovoltaic elements on both sides of the central axis, and the central axis is the center of the optical axis of the extracted bright lines. a photoreceiver that converts the left and right lights of the optical axis of the bright line into electric signals using the photovoltaic element, and an amplifier that differentially amplifies the electric signals output from the photoreceiver. and an indicator to which the output signal of the amplifier is input, moving means for moving the light receiver in the direction of misconvergence, and a display for measuring the amount of movement of the light receiver and displaying the amount of misconvergence. A convergence measuring instrument characterized by: