JPH0437896A - Monitor image inspection device - Google Patents

Abstract

PURPOSE:To enable an inexperienced person also to execute accurate inspection reducing measuring dispersion by picking up the image of a surface by a CCD camera and measuring the events of a display image based upon the image pickup data. CONSTITUTION:After connecting the CCD camera 3 to a monitor equipment 2 and setting up the image pickup enabled state of a screen, a keyboard 8 is operated to display a menu screen on a display device 6. Then, automatic measurement is started based upon a command from the keyboard 8 and a testing command is outputted from an arithmetic unit 5 to the monitor equipment 2. At the time of starting automatic measurement, a pattern is displayed on a monitor screen. When data are matched with a rated value as the result of inspection, the result is printed out by a printer 7.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a monitor image inspection device that measures the specifications of displayed figures on a monitor screen.

[Prior Art] Devices such as oscilloscopes that perform various measurements based on figures displayed on a monitor screen have been used in the past. This device adjusts and inspects at the time of manufacture whether various specifications related to a display figure, such as dimensions and display position when a predetermined figure is displayed, conform to predetermined standards. Conventionally, this inspection has been performed by directly measuring the dimensions of the displayed image by applying a measuring device such as a caliper to the screen.

[Problems to be Solved by the Invention] However, such conventional methods not only require skill and have poor measurement efficiency, but also have the problem that reading errors are likely to occur.

[Means for Solving RM] In order to solve these problems, the present invention captures an image of the display surface using a CCD sensor, and measures the specifications of the displayed image based on the captured data. be.

[Operation] Information on the display surface is captured by the CCD sensor and output as an electrical signal, so predetermined measurements are performed from the coordinates, brightness gradation, etc. of the signal.

Embodiment FIG. 1 is a block diagram showing an embodiment of the present invention.
In the figure, 1 is a test pattern generator, 2 is a monitor device that is the device under test, 3 is a CCD camera that images the screen of the monitor device 3, 4 is an image processing device, 5 is a calculation device, 6 is a display device, 7 is a printer, and 8 is a keyboard.

As shown in step 100 in FIG. 2, the apparatus configured in this way is configured to attach a CCD camera to the monitor W2 and make it possible to take an image of the screen, and then operate the keyboard 8 to display the display 6. Display the menu screen.

Then, according to instructions from the keyboard 8, automatic measurement is started as shown in step 102, and step 10
3, a test command is output from the arithmetic device 5 to the monitor device 2. Note that when automatic measurement is started in step 102, a pattern shown in FIG. 3 or 4 is displayed on the monitor screen depending on the measurement item.

Next, in step 104, if the data conforms to the standard value according to the inspection result, the result is printed out on a printer as shown in step 105, and the process is terminated. However, if it is determined in step 104 that the test result is out of specification, an adjustment mode test is performed as shown in step 107, and the tests from step 102 onwards are repeated again.

Figure 3 shows the monitor device 2 when performing inspections other than brightness measurement.
This is the screen displayed on the screen. However, the letters A to H are symbols added for convenience of explanation and are not displayed on the tube surface, and the coordinates of each point are determined by the image processing device W4.

(4) Measurement of inclination The coordinates of point A in Figure 3 are (XI, Yl), and the coordinates of point B are (
χ2. Y2), it is obtained by calculating the first equation using the arithmetic unit W5.

(b) Measurement of horizontal dimension Based on the signal obtained from the image processing device 4, the arithmetic device 5
It is obtained by counting the number of dots between the point and point D and calculating the second equation.

Horizontal dimension = a (dot) x 1... ■However,
K1 is a resolution constant in the lateral direction and has units of millimeters/dots.

(c) Measurement of vertical dimension Based on the signal obtained from the image processing device 4, the arithmetic device 5
It is obtained by counting the number of dots between the point and F point and calculating the third equation.

Vertical dimension = b (dot) × 2・・・・・・・・・［3
) However, K2 is the resolution constant in the vertical direction, and is expressed in mm/d”y.
) has units.

(d) Measurement of lateral position Let X3 be the X coordinate of the 0 point, and let HL be the lateral position origin data, then it can be found by calculating equation (2).

Horizontal position = X1-HL・・・・・・・・・・・・・・・
(4) (e) Vertical position measurement If the Y coordinate of point E is Y7 and the vertical position origin data is V, it can be obtained by calculating the +51 formula.

Horizontal position = X7-V・・・・・・・・・・・・・・・
(9) Measurement of lateral linearity As shown in Figure 5, the width of the adjacent intersections on the line segment CD, which is the lateral center line, is H1 to H6, and the lateral linearity is H17.
, the average value of the widths H1 to H6 of the intersection is HAV, and the width H1 to H6
Assuming that the representative value of is H, the representative value H is obtained by the 16th equation or the 7th equation, and the lateral linearity H11 is obtained by calculating the 8th equation.

H=H when HIIIAX-HAV≧HAV-HMIN
,AX・・・・・・(6)kAx−HAv<HA
When +N to v-, H=Hyn<・=-...-CHI
Av (g) Measurement of vertical linearity As shown in Figure 6, the width of adjacent intersections on line segment EF, which is the vertical center line, is V1 to ■6, the vertical linearity is V, and the convergence of the intersections is V1 to V6. Average value is VAv, width ■1 to ■6
Let V be the representative value of
) is obtained by calculating the formula.

Vmxx-VAv≧VAv-V+ I N (71 when v
=vlllA×・−・−・・・・・・・(9)VmAx−V
When Av<VAv-Vm I N('), v=v, 1.4
・・・・・・・・・(10) ■＾V (H) Calculate the average value of the vertical line width of the signal taken into the focus measurement CCD camera and obtained by the image processing device 4 using the arithmetic unit W5, and calculate the value. Focus measurement value.

(S) Perpendicularity Find the angle formed from the coordinates of points A, B, G, and H and the coordinates of their two adjacent points using trigonometric functions.

(N) Display the checkered black and white pattern shown in Fig. 4 on the brightness monitor device 2, and calculate the average video level of each white area and black area.Since the video signal changes depending on the gradation,
Actually, the average value of the video signal corresponding to that gradation is calculated.

[Effect of the invention] As explained above, this invention allows the upper part of the monitor screen to be
By capturing the signal with a CD camera and performing predetermined calculations corresponding to the measurement item on the obtained signal,
Items that were conventionally inspected manually can now be electrically inspected, so even unskilled personnel can perform inspections accurately and with little variation in measurement.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is a flowchart showing its operation, Fig. 3 is an image displayed on the monitor screen when the brightness side is not set, and Fig. 4 is a diagram showing the brightness. Images displayed on the monitor screen during measurement, FIG. 5 is a diagram for explaining the state when measuring horizontal linearity, and FIG. 6 is a diagram for explaining the state when measuring longitudinal linearity. 1... Test pattern generator, 2... Monitor device, 3... CCD camera, 4... Image processing device,
5... Arithmetic unit, 6... Display, 7... Printer, 8... Keyboard.

Claims (6)

[Claims] (1) Display two spots on separate parts of the monitor image, and detect the display screen with a CCD sensor,
A monitor image inspection device that calculates the number of pixels between two points and determines the length between the two points from the calculation result. (2) Display a vertical line at a position determined by the system settings on the monitor screen, display a spot at any position on the vertical line, and detect the display screen with a CCD sensor,
A monitor image inspection device that calculates the lateral positional deviation of a spot from the amount of deviation between its coordinates and the reference coordinates. (3) Display a horizontal line at a position determined by the system settings on the monitor screen, display a spot at any position on the horizontal line, detect the display screen with a CCD sensor, and set the spot to coordinates and reference coordinates. A monitor image inspection device that determines vertical position deviation from the amount of deviation. (4) Detect multiple lines displayed vertically and horizontally on the monitor screen using a CCD sensor, focus on any vertical line among the detection results, and find the intersections with all horizontal lines that intersect with that vertical line. A monitor image inspection device that focuses on an arbitrary horizontal line and determines the length between the intersections of all vertical lines that intersect with that horizontal line, and measures the average value of each as linearity. (5) A CCD sensor detects multiple lines displayed vertically and horizontally on a monitor screen, and determines the coordinates of at least the intersection of the outermost lines and its adjacent 2 lines.
A monitor image inspection device that determines the angle created from the coordinates of a point and measures the squareness. (6) A monitor image inspection device that measures luminance and brightness by displaying a checkered black and white pattern on a monitor screen and detecting the gradation of an image signal obtained when the screen is imaged by a CCD sensor.