JP4603115B2 - Image display device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image display device, and in particular, performs an optimum display position setting.
[0002]
[Prior art]
FIG. 4 is a block diagram showing a conventional image display device. In the figure, 11 is an analog-digital converter (hereinafter referred to as ADC) for converting an analog RGB signal input to the image display device into a digital signal, and 12 is an image. A PLL circuit for generating a sampling clock synchronized with a horizontal synchronizing signal input to the display device, 13 is a digital RGB signal output from the ADC 11 and a horizontal / vertical synchronizing signal (H, V signal) input to the image display device. An input control circuit, 14 is a microcomputer (hereinafter referred to as a microcomputer) for controlling the ADC 11, PLL circuit 12 and control circuit 13, 15 is an oscillator for generating a basic oscillation signal of the control circuit 13, and 16 is input from the control circuit 13. By digital RGB signal, horizontal / vertical synchronization signal and data enable signal (DE signal) A liquid crystal panel for displaying an image.
[0003]
Next, the operation will be described. The analog RGB signal input to the image display device is converted into a digital signal by the ADC 11, and the digital signal is subjected to processing that is optimally displayed on the liquid crystal panel 16 by the control circuit 13, such as display position, enlargement / reduction ratio, and smoothing. Displayed on the LCD panel. Here, all processing performed by the control circuit 13 is performed by the control circuit in accordance with a command from the microcomputer 14.
Some recent image display devices have an automatic display position optimization function that automatically adjusts the display position and display size according to the input signal even if the user does not make adjustments. Improvements are being made.
[0004]
Since the present invention has an automatic display position optimization function and is processed by a microcomputer to optimize the display position, a conventional flow of the microcomputer processing will be described below.
FIG. 5 is a flowchart of conventional display position optimization processing.
[0005]
(1) First, the microcomputer 14 reads the input frequency from the control circuit 13 and determines whether or not there is a change in the frequency (S1).
(2) If it is determined that there is no change in frequency, the timing of the signal input to the image display device is assumed to be unchanged, and the setting of the control circuit 13 remains unchanged and is not changed (S1 → S7).
[0006]
(3) If it is determined that the frequency has changed, it is determined that the timing of the signal input to the image display device has changed, and the setting of the control circuit 13 is changed so as to optimize the display position (S4).
(4) Thereafter, the MAIN routine is processed and the process returns to the beginning (S7).
Here, the MAIN routine includes normal image display processing, key input processing (adjustment button input processing), and the like.
[0007]
[Problems to be solved by the invention]
Since the conventional image display device is configured as described above, the change in the frequency of the synchronizing signal input to the image display device is observed, and the display position is optimally processed only when it is determined that the change has occurred. It was. Therefore, there is a problem that an image deviated from the optimum display position is displayed when the frequency of the synchronization signal is the same but the phase of the synchronization signal and the image signal is changed.
[0008]
The present invention has been made to solve the above-described problems. Even when the frequency of the synchronization signal input to the image display device is the same, the image of the synchronization signal and the image signal change in phase. The purpose is to display the display position optimally.
[0009]
[Means for Solving the Problems]
(1) In the image display device according to the present invention, an image signal and a synchronization signal synchronized with the image signal are separately input, and an automatic display position for adjusting a display position of an image generated based on the image signal In the image display device having an adjustment function, when the change in the input frequency of the synchronization signal or the change in the input resolution of the image signal is detected, the image generated by the change in the phase between the image signal and the synchronization signal The display position is adjusted so as to reduce the deviation of the display position from the optimal display position, and the optimal display position setting for determining the display position of the image is repeatedly executed a plurality of times.
[0010]
(2) An image display device having an automatic display position adjustment function that adjusts a display position of an image generated based on an image signal and a synchronization signal synchronized with the image signal that are separately input. , When a change in the input frequency of the synchronization signal or a change in the input resolution of the image signal is detected, a change in the phase of the image caused by the phase change between the image signal and the synchronization signal is detected within a predetermined period. The display position is adjusted so as to reduce the deviation of the display position from the optimal display position, and the display position optimal setting for determining the display position of the image is repeatedly executed a plurality of times.
[0011]
(3) An image display device having an automatic display position adjustment function for separately inputting an image signal and a synchronization signal synchronized with the image signal and adjusting a display position of an image generated based on the image signal When the change in the input frequency of the synchronization signal or the change in the input resolution of the image signal is detected, the change from the optimum display position of the image caused by the change in the phase between the image signal and the synchronization signal is detected. The display position is adjusted so as to reduce the display position shift, and the optimum display position setting for determining the display position of the image is repeatedly executed a predetermined number of times.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
Embodiment 1 of the present invention will be described below with reference to the drawings. FIG. 1 is a flowchart for explaining the operation of the first embodiment. The hardware configuration is the same as that of FIG. 4 of the prior art.
[0013]
When the frequency of the synchronization signal input to the image display device does not change and only the phase of the synchronization signal and the image changes, this mainly occurs when the personal computer is turned on or when the resolution / refresh rate is changed. In these cases, since the display is almost completed in several seconds until the display is stabilized at the final display, the optimum setting process of the display position may be performed only during that time. This will be described with reference to the flowchart of FIG.
In the flow of FIG. 1, the timer is formed in the microcomputer 14 of FIG.
[0014]
(1) First, it is determined whether or not the frequency of the synchronization signal input to the image display device has changed (S1).
(2) When the frequency changes, the timer time for measuring the period for performing the subsequent position optimization setting process is set and started (S2).
For example, the set time is about 2 to 3 seconds.
[0015]
(3) Then, display position optimum setting processing is performed (S4).
The display position optimum setting processing time is usually about 0.1 seconds.
(4) Check the elapsed time of the started timer (S5).
(5) If the set time has elapsed, the timer is stopped (S6).
[0016]
(6) If the set time has not elapsed, the timer enters the main routine without stopping (S5 → S7).
(7) When the processing of the main routine is completed (S7), the process returns to the determination of whether the input frequency has changed (S1).
[0017]
(8) If the input frequency has not changed (S1 → S3),
(9) It is confirmed whether the timer is operating (S3).
(10) If the operation is in progress, the optimum display position is set (S4). If the timer is stopped, the main routine is entered (S3 → S7).
[0018]
According to the first embodiment of the present invention, when the frequency of the input signal changes, after the change, the display position optimum setting is repeated a plurality of times within a certain period, whereby the synchronization input within this certain period is performed. Even when only the synchronization signal and the phase of the image change without changing the frequency of the signal, the image can be displayed at the optimum position.
[0019]
Embodiment 2. FIG.
FIG. 2 shows a flowchart when a change in resolution is detected. The input frequency change detection unit in step S2 in FIG. 1 is changed to the resolution change detection unit in step S8 in FIG.
[0020]
According to the second embodiment of the present invention, when the input resolution changes, the display position optimum setting is repeated a plurality of times within a certain period after the change. Even when only the synchronization signal and the phase of the image change without changing the frequency, the image can be displayed at the optimum position.
[0021]
Embodiment 3 FIG.
The third embodiment is a combination of the first embodiment and the second embodiment.
The third embodiment has both the processing flow of FIG. 1 and the processing flow of FIG. 2, and if the input resolution changes during the processing of the flow of FIG. 1, the processing moves to the flow of FIG. Execute this flow. Further, if the input frequency changes during the processing of the flow of FIG. 2, the processing moves to the flow of FIG. 1 and this flow is executed.
In these processes, the timer is reset once, and the display position optimum setting is repeatedly performed within a certain period from that point.
[0022]
As described above, in the third embodiment, even when both the input frequency and the input resolution change in succession, the optimum display position is set from the first change until a certain period after the last change. It has the effect of repeatedly executing and displaying the image at the optimum position.
[0023]
Embodiment 4 FIG.
The fourth embodiment is also a combination of the first embodiment and the second embodiment as in the third embodiment, and FIG. 3 shows a processing flow of the fourth embodiment.
In the figure, a change in input frequency is detected in step S1, and a change in input resolution is detected in step S8. Since the subsequent flow is the same as that of FIG. The effect is also the same as that of the third embodiment.
[0024]
Embodiment 5 FIG.
In the first to fourth embodiments, when the input frequency or the input resolution changes, the display position optimum setting is repeated a plurality of times within a certain period to display the image at the optimum position. In this fourth embodiment, the input is performed. When the frequency or the input resolution changes, the display position optimum setting is repeated a certain number of times after the change.
[0025]
Specifically, in FIG. 1, FIG. 2 and FIG. 3, a counter is provided instead of a timer, and the counter is stopped when the number of display position optimum setting (step S4) is counted by this counter and reaches the set number. The setting process ends.
[0026]
As described above, the fifth embodiment has the effect of executing the display position optimum setting a predetermined number of times and displaying the image at the optimum position regardless of which of the input frequency and the input resolution changes.
[0027]
【The invention's effect】
As described above, according to the present invention, when the change of the input frequency or the change of the input resolution is detected, the optimum display position is repeatedly executed a plurality of times, so that the image can be displayed at the optimum position.
[Brief description of the drawings]
FIG. 1 is a flowchart of processing operations of an image display apparatus according to Embodiment 1 of the present invention.
FIG. 2 is a flowchart of processing operations of an image display apparatus according to Embodiment 2 of the present invention.
FIG. 3 is a flowchart of processing operations of an image display apparatus according to Embodiment 4 of the present invention.
FIG. 4 is a block diagram of an image display device of the related art and the present invention.
FIG. 5 is a flowchart of processing operations of a conventional image display apparatus.
[Explanation of symbols]
11 analog-digital converter (ADC), 12 PLL circuit,
13 control circuit, 14 microcomputer,
15 oscillator, 16 liquid crystal panel.

Claims (3)

In an image display device having an automatic display position adjustment function for separately inputting an image signal and a synchronization signal synchronized with the image signal and adjusting a display position of an image generated based on the image signal,
When a change in the input frequency of the synchronization signal or a change in the input resolution of the image signal is detected, the display position from the optimum display position of the image caused by a change in phase between the image signal and the synchronization signal An image display device, wherein the display position is adjusted so as to reduce the shift, and the display position optimal setting for determining the display position of the image is repeatedly executed a plurality of times. In an image display device having an automatic display position adjustment function for separately inputting an image signal and a synchronization signal synchronized with the image signal and adjusting a display position of an image generated based on the image signal,
When a change in the input frequency of the synchronization signal or a change in the input resolution of the image signal is detected, an optimal display of the image caused by a change in phase between the image signal and the synchronization signal within a predetermined period An image display apparatus, wherein the display position is adjusted so as to reduce the deviation of the display position from the position, and the optimum display position setting for determining the display position of the image is repeatedly executed a plurality of times. In an image display device having an automatic display position adjustment function for separately inputting an image signal and a synchronization signal synchronized with the image signal and adjusting a display position of an image generated based on the image signal,
When a change in the input frequency of the synchronization signal or a change in the input resolution of the image signal is detected, the display position from the optimum display position of the image caused by a change in phase between the image signal and the synchronization signal An image display device, wherein the display position is adjusted so as to reduce the shift, and the optimum display position setting for determining the display position of the image is repeatedly executed a predetermined number of times.

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