JPS59201591A - Crt display device - Google Patents

Abstract

PURPOSE:To identify easily a picture whether it is a television picture or a data picture from a personal computer by providing a shadow to the data picture from the personal computer. CONSTITUTION:An OR gate 4, a monostable multivibrator 5, an amplifier 6 and a transistor 7 or the like are provided to form a shadow signal. The data picture from the personal computer 2 is applied to a signal mixing circuit 32 in a television circuit 31 and displayed on a CRT33, then the shadow signal is formed and applied to the signal mixing circuit 32 to provide the shadow to the data picture.

Description

Detailed Description of the Invention - <Technical Field> The present invention connects a personal computer to a television receiver, and displays data images from the personal computer simultaneously on a CRT screen by superimposing them on a television broadcast image. The present invention relates to a CRT display device that can be used.

Recently, personal computers have come to be used in ordinary households. Attempts are now being made to connect a home color television receiver to a personal computer as a CRT Nice Play device and display data from the personal computer on the color television receiver.

<Prior Art> FIG. 1 is a schematic diagram of a general CRT display device showing a state in which a personal computer is connected to a color television receiver. First, referring to Figure 1, the data entered from the keyboard 1 is
, R, G, and B signals for displaying the data on the color television receiver 3 are applied to a signal mixing circuit 32 included in the television circuit 31 . Then, the R, G, and B signals are sent to the CRT via the signal mixing circuit 32.
, 33, and characters or graphs are displayed.

By configuring the CRT display device in this way, data images such as various characters and graphs can be displayed using the color television receiver 3 as a monitor. Furthermore, recently, a CRi' display device has been devised that displays data from a burner computer superimposed on a color television broadcast screen.

<Problem> By the way, in such a CRT display device, a personal computer color data image is superimposed and displayed on a television image (including not only broadcast images but also images reproduced by a VTR or video disc player, etc.). Depending on the content of the television image, for example, characters or graphs may be included in news programs or educational programs. There were deficiencies that were difficult to discern.

Purpose> The present invention has been made in view of the above points, and is intended to improve CR
7. A CRT that can simultaneously display a television image and a data image from a personal computer on its screen and that does not cause the user to confuse the two images.
The present invention provides a display device.

Particularly, the present invention provides a CRT display device that allows a user to easily identify which image is a data image from a personal computer by adding shading to the data image.

<Examples> The present invention will be described below according to examples shown in the drawings. Second
The figure shows a block diagram of one embodiment of the invention, in which the first
The same parts as those in the figure are given the same reference numerals. Here, in particular, an OR gate 4, a monostable multivibrator 5, an amplifier 6, an I.Langistaff, etc. are added to create a shadow signal.

Now, using the CRT display device of the above embodiment, the CRT is used as data output from the personal computer 2.
The operation will be explained when the R, G, and B outputs for projecting a fat character image as shown in FIG. 3(a) are derived.

In this case, the character on the CR7 screen "A line that crosses the shoes, for example, the line A-A', the personal computer 2
At least one of the R, G, and B outputs is 11 H/J
Since the output from the output is 8, a rectangular wave pulse as shown in FIG. 3(b) is derived from the OR gate 4 and supplied to the monostable multivibrator 5. At this time, the monostable multivibrator 5 is triggered at the falling edge of the pulse, and a positive polarity shot pulse with a constant pulse width To as shown in FIG. 3(c) is output, and the transistor 7 supplied to the base of When the transistor 7 remains on only during the pulse period, an inverted pulse signal of negative polarity is derived from the collector as shown in FIG. Here, it is superimposed on a television image signal, particularly a luminance (Y) signal. As a result, a character image from the personal computer 2 is displayed on the screen of the CRT 33 as shown in FIG. 3(a).
``The trailing edge of I is shaded black; the background television image is not shaded in any way.

In the above embodiment, the width of the shadow projected on the screen can be adjusted arbitrarily by varying the value of the output pulse width To of the multivibrator 5 using a pulse width adjustment variable resistor 8 attached to the monostable multivibrator 5. Can be set to .

However, in this case, if the pulse rlJTo is made so wide that the shadow of the character on the screen overlaps a part of the adjacent character image, or if the horizontal spacing between the characters themselves or adjacent characters is narrow, Even when the monostable multivibrator 5 outputs a positive polarity shot pulse, the subsequent character output derived from the personal computer 2 causes the output of the OR gate 4 to go to ■H// level, and the output of the amplifier 6 also goes to \H. “
At this time, the transistor 7 is in a cut-off state, and therefore no shadow signal is derived from the collector. As a result, the shadow of one character on the screen erodes part of the adjacent character (r:i).

In the above embodiment, when a color television receiver, an imager, and a personal computer are connected, color characters (() from the personal computer are displayed on the CRT screen). It is also possible to attach a computer, and it can also be implemented when a black and white television receiver and a personal computer are connected.

<Effects> As described above, according to the present invention, there is provided a CRT display which can connect a personal computer to a television receiver and display data images from the personal computer simultaneously by superimposing the television image on the CRT screen. In devices, especially personal computer data images, are shaded, so the user can instantly distinguish between the background television image and this data image, so even if the television Even if characters or data are displayed on the screen in a broadcast news program or the like, there will be no confusion.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of a CRT device that connects a personal computer to a color television receiver.
FIG. 2 is a lock diagram of one embodiment of the present invention, and FIG. 3 is an example of a CRT screen and a signal waveform diagram at that time for explaining the operation of the same embodiment.

Claims (1)

[Claims] 1. In a CRT display device in which a personal computer is connected to a television receiver and a data image from the personal computer can be simultaneously projected and displayed on a CRT screen by superimposing it on a television image, shading is created based on the data output from the personal computer. A CRT Nice Play device characterized in that the shading signal is mixed with the television image signal together with the data output to shade the data image on the CRT screen.