JPH07319422A - Display device - Google Patents

Abstract

PURPOSE:To provide a high quality image free from the feeling of incompatibility when a TV image display and a VTR image display are mutually switched. CONSTITUTION:This device is provided with a VTR circuit 101 outputting a VTR signal including the VTR image data and the switching noise data, a TV signal circuit 102 outputting a TV signal being the TV image data, a switch circuit 103 outputting either the VTR signal or the TV signal, a mask circuit 104 outputting the TV signal when the signal from the switch circuit 103 is the VTR signal, and outputting the signal inserted with the mask data into the front/behind of the VTR image data when the signal from the switch circuit 103 is the TV signal, a liquid crystal module 106 and a control circuit 105 setting an image display location in the liquid crystal module 106 so that the TV image data are located on the whole screen in the case of the TV signal, and setting it so that the mask data are located on the upper/lower of the screen and the VTR image data are located between them in the case of the VTR signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device for displaying a general television (hereinafter abbreviated as "TV") signal or a video tape recorder (hereinafter abbreviated as "VTR") signal.

[0002]

2. Description of the Related Art In recent years, liquid crystal displays have been increasingly used as VTR monitors instead of CRT displays. Therefore, in the case of a liquid crystal display that displays almost all effective scanning lines, the VT
There was a particular problem that R switching noise appeared. To solve this problem, for example, Japanese Patent Laid-Open No. 3-1179801
There is a proposal as shown in the publication.

FIG. 4 shows a block diagram of this conventional display device. Here, a case where a liquid crystal module is used for image display will be described. In FIG. 4, 101 is V
A VTR circuit that performs TR signal processing, 102 a TV signal circuit that performs TV signal processing, and 103 a VTR circuit 101 and a T
A switching circuit for switching the V signal circuit 102, 104 a mask circuit for inserting mask data of a black level signal when the selection signal Sel from the switching circuit 103 is at a high level, 4
01 is a control circuit for setting the image display period, 10
6 is a liquid crystal module.

FIG. 5 shows a timing waveform diagram in the conventional example. In FIG. 5, Vd shown in (1) is 1
Vertical sync signal with a field cycle, S shown in (2)
ig1 is an output of the VTR circuit 101, which is V including the VTR image data and switching noise data (SND).
TR signal, Sig2 shown in (3) is the TV signal circuit 102
Is a TV signal which is TV image data, and Sel shown in (4) is an output of the switching circuit 103 and is the VTR circuit 101.
When is selected, it becomes high level and the TV signal circuit 10
When 2 is selected, it is a low-level selection signal, and the low-level period of this selection signal Sel is A period,
The period of high level is B period. Further, Sig shown in (5) is an output signal of the switching circuit 103, and during the period A, the TV signal Sig2 is the output signal Sig of the switching circuit 103.
In the period B, the VTR signal Sig1 is switched to the switching circuit 103.
Output signal Sig. Mask shown in (6) is a mask signal output from the mask circuit 104. This mask signal Mask is the TV signal Sig2 in the period A, and B
During the period, the VTR signal Sig1 becomes a signal in which the lower mask data (LM) having a black level is inserted in the switching noise data (SND) portion. St shown in (7) is an output of the control circuit 105 and is a start signal for setting the image display period.

FIG. 6 shows a conventional liquid crystal module 10.
6 is a diagram showing an image display of FIG. In FIG.
(1) shows the image display in the period A shown in FIG. 5, and (2) shows the image display in the period B shown in FIG. 5, respectively. In the conventional display device configured as described above,
The operation will be described below with reference to FIGS. 4, 5, and 6.

Now, from the VTR circuit 101, the VTR signal S
ig1 is output, and the TV signal S is output from the TV signal circuit 102.
Assuming that ig2 is output, the operation in the period A in which TV image data is displayed on the liquid crystal module 106 will be described first. In this case, the switching circuit 103 uses the TV signal Sig.
2 is output. In the mask circuit 104, the selection signal Sel
Is low level, the TV signal Sig2 is directly output as the mask signal Mask. Further, the control circuit 401 outputs the start signal St. And FIG.
As shown in (1), the TV image data is displayed on the entire screen.

Next, the operation in the period B for displaying the VTR image data on the liquid crystal module 106 will be described. In this case, the switching circuit 103 outputs the VTR signal Sig1.
Since the selection signal Sel is at a high level, the mask circuit 104 outputs the mask signal Mask in which the lower mask data (LM) is inserted in the switching noise data (SND) portion. Further, the control circuit 401 outputs the start signal St similar to that in the period A. Then, as shown in (2) of FIG. 6, the lower mask data (L
M) is displayed, and the VTR image data is displayed on the other upper part of the screen.

[0008]

SUMMARY OF THE INVENTION In the above conventional configuration,
In the case of TV image data display, it is displayed on the entire screen,
In the case of VTR image data display, the lower part of the screen is displayed in black with the lower mask data, and the VTR image data is located at the upper part of the screen, which deteriorates the balance of the entire screen.
Therefore, when switching between the TV image display and the VTR image display, there is a problem that a sense of discomfort occurs and a high-quality image cannot be obtained.

SUMMARY OF THE INVENTION In view of the above points, an object of the present invention is to provide a display device capable of obtaining a high quality image without a feeling of strangeness when switching between TV image display and VTR image display.

[0010]

The display device of the present invention comprises:
A VTR circuit that performs signal processing of a video tape recorder and outputs a VTR signal including VTR image data and switching noise data, a TV signal circuit that performs TV signal processing and outputs a TV signal that is TV image data, and a VTR circuit And a switching circuit connected to the TV signal circuit to output one of the VTR signal and the TV signal, and when the signal from the switching circuit is a TV signal, the TV is not processed.
A mask circuit that outputs a signal and outputs a signal in which mask data is inserted before and after the VTR image data of the VTR signal when the signal from the switching circuit is the VTR signal, and an image that displays an image by the output signal of the mask circuit The display module and the image display position in the image display module are displayed on the TV.
In the case of a signal, the TV image data is set so as to be located on the entire screen, and in the case of a VTR signal, the control data is set so that the mask data is located above and below the screen and the VTR image data is located between the mask data. ing.

[0011]

According to the configuration of the present invention, when TV image data is displayed, it is displayed on the entire screen of the image display module,
When displaying the VTR image data, mask data is inserted before and after the VTR image data in the mask circuit, and the control circuit sets the image display position in the image display module so that the mask data is positioned above and below the screen. By setting so that the VTR image data is located between the two, the mask area can be evenly divided into the upper and lower parts of the screen and the VTR image data can be displayed in the center of the screen. As a result, when switching between the TV image display and the VTR image display, it is possible to obtain a high-quality image with no discomfort.

[0012]

1 is a block diagram of a liquid crystal display device according to an embodiment of the present invention. Here, a case where a liquid crystal display is used as in the conventional example will be described. In FIG. 1, reference numeral 101 denotes a V which performs signal processing of the VTR.
TR circuit, 102 is a TV signal circuit for performing TV signal processing,
Reference numeral 103 is a switching circuit for switching between the VTR circuit 101 and the TV signal circuit 102, 104 is a mask circuit for inserting mask data of a black level signal when the selection signal Sel from the switching circuit 103 is at a high level, and 106 is a liquid crystal module, These are the same as in the conventional example, and the same reference numerals are added. The difference from the conventional example is that 105 is provided with a control circuit for changing the timing of the start signal St by the selection signal Sel from the switching circuit 103.

FIG. 2 shows a timing waveform diagram in this embodiment. In FIG. 2, Vd shown in (1)
Is a vertical sync signal with one field as a cycle, Sig1 shown in (2) is a VTR signal that is the output of the VTR circuit 101 and includes VTR image data and switching noise data (SND), and Sig2 shown in (3) is a TV signal circuit. 1
The output of 02 is the TV signal which is the TV image data, and Sel shown in (4) is the output of the switching circuit 103 and the VTR circuit 1
The selection signal is a high level when 01 is selected and a low level when the TV signal circuit 102 is selected. The selection signal Sel has a low level period A period and a high level period B period. I am trying. Also,
Sig shown in (5) is the output signal of the switching circuit 103, the TV signal Sig2 becomes the output signal Sig of the switching circuit 103 during the A period, and the VTR signal Sig1 becomes the output signal Sig of the switching circuit 103 during the B period. These (1) ~
The signal shown in (5) is the same as in the conventional example, and the points different from the conventional example are the mask signal Mask shown in (6) and the start signal St shown in (7). Mask signal M shown in (6)
ask is an output of the mask circuit 104, and T is T during the A period.
The V signal Sig2 is similar to the conventional example, but B
In the period, the upper mask data (UM) having a black level is inserted before the VTR signal Sig1, and the lower mask data (LM) having a black level is also inserted in the switching noise data (SND) portion. Different from the conventional example.
Further, the start signal St shown in (7) is an output of the control circuit 105 and sets the image display period, but the timing is different between the A period and the B period, which is different from the conventional example.

FIG. 3 is a diagram showing an image display on the liquid crystal module in this embodiment. In FIG.
(1) shows the image display in the period A shown in FIG. 2, and (2) shows the image display in the period B shown in FIG. The operation of the display device of this embodiment configured as described above will be described below with reference to FIGS. 1, 2, and 3.

Now, from the VTR circuit 101, the VTR signal S
ig1 is output, and the TV signal S is output from the TV signal circuit 102.
Assuming that ig2 is output, the operation in the period A in which TV image data is displayed on the liquid crystal module 106 will be described first. In this case, the switching circuit 103 uses the TV signal Sig.
2 is output. In the mask circuit 104, the selection signal Sel
Is low level, the TV signal Sig2 is directly output as the mask signal Mask. Further, in the control circuit 105, since the selection signal Sel is at the low level, T
Start signal S for displaying an image from the beginning of V image data
Output t. Then, as shown in (1) of FIG. 6, TV image data is displayed on the entire screen.

Next, the operation in the period B in which the VTR image data is displayed on the liquid crystal module 106 will be described. In this case, the switching circuit 103 outputs the VTR signal Sig1.
Since the selection signal Sel is at the high level, the mask circuit 104 outputs the upper mask data (UM) before the VTR image data.
Is a mask signal Ma in which the lower mask data (LM) is inserted in the switching noise data (SND) part.
Output sk. Further, since the selection signal Sel is at the high level, the control circuit 105 outputs the start signal St for displaying an image from the beginning of the upper mask data (UM). Then, as shown in FIG. 6B, the upper mask data (UM) is displayed on the upper portion of the screen of the liquid crystal module 106.
, Lower mask data (LM) is displayed at the bottom of the screen, and VTR image data is displayed at the center of the screen in the meantime.

As described above, according to this embodiment, when the TV image data is displayed, the entire screen of the liquid crystal module 106 is used for display, and when the VTR image data is displayed, the mask circuit 104 is used. Mask data is V
By inserting the TR image data before and after the TR image data and setting the timing of the start signal St from the control circuit 105 earlier than when displaying the TV image data, and shifting the image display position, as shown in (2) of FIG. , The number of upper and lower mask lines (or mask area) can be made equal,
VTR image data can be displayed in the center of the display screen. As a result, when switching between the TV image display and the VTR image display, it is possible to obtain a high-quality image with no discomfort. At the same time, a powerful high-quality image can be obtained on a large screen even in the normal TV image data display.

In this embodiment, a liquid crystal display is used for explanation, but it goes without saying that a plasma display, an EL display or the like may be used.

[0019]

As described above, according to the present invention,
When displaying TV image data, it is displayed on the entire screen of the image display module. When displaying VTR image data, mask data is inserted before and after the VTR image data in the mask circuit, and the image is displayed by the control circuit. By setting the image display position in the module so that the mask data is located above and below the screen and the VTR image data is located between the mask data, the mask area is evenly divided into the top and bottom of the screen, and the VTR image is displayed in the center of the screen. The data can be displayed. As a result, TV image display and V
It is possible to obtain a high-quality image with no discomfort when switching between TR image display. At the same time, a normal TV
Even in image data display, it is possible to obtain a powerful high-quality image on a large screen, and its practical effect is great.

[Brief description of drawings]

FIG. 1 is a block diagram of a display device according to an embodiment of the present invention.

FIG. 2 is a timing waveform diagram in the example.

FIG. 3 is an image display diagram in the example.

FIG. 4 is a block diagram of a conventional display device.

FIG. 5 is a timing waveform chart in a conventional example.

FIG. 6 is an image display diagram in a conventional example.

[Explanation of symbols]

 101 VTR circuit 102 TV signal circuit 103 Switching circuit 104 Mask circuit 105 Control circuit 106 Liquid crystal module

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location H04N 5/66

Claims (1)

[Claims] 1. A VTR circuit for performing signal processing of a video tape recorder and outputting a VTR signal including VTR image data and switching noise data, and a TV image data T for performing TV signal processing.
A TV signal circuit for outputting a V signal; and the VT connected to the VTR circuit and the TV signal circuit.
A switching circuit that outputs one of an R signal and a TV signal, and outputs the TV signal without processing when the signal from the switching circuit is the TV signal, and the signal from the switching circuit is the VTR. If it is a signal, V of the VTR signal
A mask circuit that outputs a signal in which mask data is inserted before and after the TR image data, an image display module that displays an image according to the output signal of the mask circuit, and an image display position in the image display module when the TV signal is used. A control circuit for setting the TV image data so that it is located on the entire screen, and for the VTR signal, the mask data is located above and below the screen, and the VTR image data is located between the mask data; Display device.