JPS62216489A - Inspection instrument for color display device - Google Patents

Abstract

PURPOSE:To omit the wiring of a synchronizing clock separately from an inspected part and to simplify the constitution of a circuit by using the one color of three primary colors R, G, B in an inspected signal as a clock and inspecting the signals of the other two colors. CONSTITUTION:Initially, for instance, when the R (red) signal is used for generating a synchronizing pulse, the input of the R signal to the control part 3 of the inspection is made the repetition of 'H' and 'L', the inspected part 3 outputs the same signal as it, a synchronizing pulse generating part 7 receives the signal, multiplying it by 2, and using it as a synchronizing pulse for making access to the data of the G (green) and the B (blue) stored in a reference data memory 1. This reference data memory 1 operates similarly to a frame buffer memory generally used in a color CRT display device. Since the reading thereof is performed in parallel, the read signal is converted to the serial signal, synchronized with an input signal from the inspected part and compared by comparison parts 2-2, 2-3. In such a case, the synchronizing pulse multiplied by 2 is also used for the synchronization of the comparison parts.

Description

[Detailed Description of the Invention] [Summary] The CRT control section of a color display device is inspected using a test pattern stored in memory! In a device that compares the same test pattern signal output from the inspection section, the signal of one of the three primary colors of RGB in the signal to be inspected is used as a clock to inspect the signals of the other two colors. Separate wiring of synchronization clocks from the inspection section is omitted, and the circuit configuration is simplified.

[Industrial application field]

The present invention relates to a color CRT display device, and more specifically, the present invention relates to a color CRT display device. #[Regarding the inspection circuit of the l1 section.

Color CR used as terminals for information processing equipment, etc.
In the T display device, the CRT control unit, which controls displaying predetermined characters and graphic data in a predetermined position on the display screen in a predetermined mode, is conventionally assembled together with the CRT part and then assembled as a whole. Various inspections have been performed mainly by visual inspection, but as a recent trend, the CRT control unit has been manufactured as an independent component and inspected.

Therefore, it has been desired to provide such a simple test circuit.

[Problems to be solved by the prior art and the invention] CI of color CRT display device? In a conventional inspection device for a T control section, a test pattern is displayed on a display device using a section to be inspected, and the test pattern is visually read. Therefore, not only do high-precision graphic patterns and the dot structure of Chinese characters fail to be read, but the inspection workers also suffer from eye fatigue and require a large amount of man-hours.

As a countermeasure, a method is used in which a test pattern prepared in advance is stored in a reference data memory, the same test pattern is output to the part under test, and the signal is compared with the data in the corresponding reference memory. .

However, in this method, the dot clock and horizontal and vertical synchronization signals are input from the part to be inspected into the inspection equipment, and the address on the reference data memory is specified from these three signals to access it. was. Therefore, wiring for drawing in these three signals is required, which complicates the circuit.

The present invention was invented in view of these points.
It is an object of the present invention to provide an inspection device for a color display device that is capable of comparing output signals of parts to be inspected with a simple configuration.

[Means for solving problems]

Therefore, the present invention provides a method for comparing a synchronization pulse for accessing the reference data memory 1 and the comparison section 2 using one of the three primary color signals sent from the section to be inspected 3. The above problem can be solved by providing a synchronization pulse generator 7 that generates a synchronization pulse for timing.

[For production]

First, for example, when using an R (red) signal to generate synchronization pulses, the R signal input to the control unit 3 to be tested is set to "H".
The unit under test 3 outputs the same signal, and the synchronous pulse generator 7 receives that signal and converts it into 2
It is multiplied and used as a synchronization pulse for accessing G (green) and B (blue) data stored in the reference data memory 1.

This reference data memory 1 functions similarly to a frame buffer memory commonly used in color CRT display devices. Since the readout is done in parallel, the readout signals are converted into serial signals and compared by the comparator 2-2, 2-3 in synchronization with the input signal from the tested section. At this time, the doubled synchronization pulse is also used for synchronization of this comparison section.

〔Example〕

The gist of the present invention will be specifically explained below with reference to embodiments shown in the drawings.

FIG. 1 shows the configuration of the first embodiment in a block diagram, and FIG. 2 shows its waveform diagram. In Fig. 1, numeral 1 is a reference data memory, 2 is a signal comparison section, and 3 is a color CR which is a section to be inspected.
4 is an original pulse selection section, 5 is a multiplication section, 6 is a test control section, 7 is a synchronization pulse generation section, 8 is a display section, and 9 is a parallel/serial conversion circuit.

The reference data memory 1 is a high-speed RAM that functions as a frame buffer memory of a display device, and stores test patterns in advance in this inspection device. This test pattern may be created by taking an image with a camera, or may be created by a computer program.

The signal comparison section 2 compares the signals of each of the three primary colors outputted from the inspected section 3 with the data outputted from the reference data memory 1 for each synchronization pulse from the inspection control section 6. As a result of the comparison, if the compared data are not the same, the comparison section outputs a warning signal. This warning signal is displayed at the data position on the display section 8 of the inspection device.

The original pulse selection unit 4, according to instructions from the inspection control unit 6,
One of the three primary color signals from the inspected section 3, for example, the R signal, is selected as the original pulse for creating the clock pulse. On the other hand, when R is selected as the original pulse, the input R signal to the inspected section 3 is set to repeat "11" and "L". The test section 3 outputs the same "H" and "L" repetitions and sends it to the multiplier section 5 via the original pulse selection section 4-1.In this case, the other two signal systems, namely G and This is a circuit that handles B.

The multiplier 5 doubles the R repetition pulse and outputs it to the controller 6 as a clock pulse.

The inspection control unit 6 sequentially addresses the reference data memory 1 based on this manually inputted clock pulse, and outputs the stored data. Since this output data is a parallel signal, it is also controlled by the synchronization pulse from the test control section 6 and converted into serial data by the parallel/serial conversion circuit 9.

The data that is serially converted and output to the comparison section 2 is configured to be at the same display address as the data signal directly input from the section to be inspected 3 to the comparison section.

The control unit 6 has respective comparison units 2-2.2- for G and B signals.
3, a synchronizing pulse is also sent out to specify the timing of comparison.

The waveform diagram in Fig. 2 shows “11” of R as the original pulse signal.
``B repeat signal, its doubled clock signal, and the G and B signals to be tested.

After completing the inspection of the G and B signal systems using the above procedure,
Either G or B is switched for clock pulse generation by the original pulse selection unit 4 as in the case of R above,
Inspect the R signal system.

As can be seen from the above description, this inspection apparatus can inspect whether the CRT control section, which is the section to be inspected 3, has correctly transmitted and processed color image signals.

Each comparison section 2-1 to 2-3 outputs a warning signal when the comparison results and compared data are not the same, but the warning signal is only displayed on the display section of this inspection device as described above. Rather, it is used in an automatic inspection mechanism, such as for classifying the parts 3 to be inspected.

〔Effect of the invention〕

As described above, according to the present invention, a test circuit for a CRT II control section can be configured by simply adding a very simple circuit, and accurate tests can be performed automatically, contributing to increased efficiency in the test process. However, its industrial effects are enormous.

[Brief explanation of drawings]

FIG. 1 is a block diagram of one embodiment of the present invention, and FIG. 2 is a circuit waveform diagram. In the figure, 1 is a reference data memory, 2 is a comparison section, 4 is an original pulse selection section, 5 is a multiplication section, 6 is a control section, and 7 is a synchronization pulse generation section.

Claims (1)

[Claims] In order to test a CRT control unit 3 used in a color CRT display device, there is provided a reference data memory 1 for storing test pattern data provided in advance, and an output signal from the unit under test 3. , the corresponding reference data memory 1
In an inspection device having video comparison units 2-1 to 2-3 that compare the data in each of the three primary colors of red, green, and blue, among the signals of the three primary colors sent from the unit to be inspected 3, A pulse for accessing the reference data memory 1 using any one signal of the comparators 2-1 to 2-2-
1. An inspection device for a color display device, characterized in that a synchronous pulse generator 7 is provided for generating a pulse that takes a comparison timing of 3.