JPH07225565A - Dot matrix display - Google Patents

Abstract

PURPOSE:To provide an image display with less picture quality deterioration even when an interpolation enlargement processing of non-integer times is performed, and display is performed. CONSTITUTION:This device is a dot matrix display device provided with an image data size detection circuit l detecting the size of the input image data (mXn dots), a data interpolation circuit 2 processing the input image data with the linear interpolation enlargement as necessary, a display panel (liquid crystal panel) 3 whose number of pixels displaying an image are MXN dots, a voltage generation circuit 4 generating the driving voltage of the display panel 3 and a voltage controller 5 controlling the voltage generation circuit 4, and automatically changing the luminance of the display panel 3 and displaying a non-integer times enlargement image with less picture quality deterioration.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dot matrix display device.

[0002]

2. Description of the Related Art Conventionally, image data from a personal computer or the like is
There are various resolutions depending on the mode, and when displaying these image data, a CRT display can be relatively easily multi-scanned by a technique such as constant amplitude of the deflection circuit. There was no problem because an image without image quality deterioration was obtained without particularly complicated processing.

However, in the liquid crystal panel, the number of pixels (M × N dots) is determined from the design stage, and if the input image data (m × n dots) matches the number of pixels of the liquid crystal panel, the input image data Each dot and each pixel of the liquid crystal panel have a one-to-one correspondence, and it was possible to display an image using the full screen, but if the input image data is smaller than the number of pixels of the liquid crystal panel, how to display it? Becomes an important issue.

Even when the number of pixels of the liquid crystal panel is different from the number of dots of the input image data as described above, if the number of dots of the input image data is multiplied by an integer, the number of pixels of the liquid crystal panel is obtained, that is, an enlargement process of an integral multiple is performed. In that case, there is no problem in that it can be easily enlarged without using data interpolation or the like, but it becomes a big problem when the number of pixels of the liquid crystal panel is a non-integer multiple of the input image data. In such a case, only the number of dots of the input image data is displayed using a part of the screen without performing the interpolation enlargement process, or the input image data is subjected to the interpolation enlargement process with the number of pixels of the liquid crystal panel. From this, there were two ways to use the full screen to display an image.

The same applies to display devices such as EL and plasma displays.

[0006]

However, in the method of displaying only the number of dots of the input image data by using a part of the screen without performing the interpolation enlargement processing, the display image becomes smaller than the screen, Among them, there is a problem that a played portion that is unrelated to the displayed image occurs. Even with the method of displaying after the interpolation enlarging process, if the interpolation enlarging process of a simple algorithm occurs, problems such as jagged appearance of the contour part of the picture occur, the image quality deteriorates, and a more advanced algorithm However, if the interpolation enlargement process is performed, the circuit becomes complicated and the cost becomes high.

The present invention is intended to solve such a conventional problem, in which the display panel is always fully used for image display and display, and non-integer multiple interpolation enlargement processing is performed by a simple algorithm. An object of the present invention is to provide a dot matrix display device in which the image quality is little deteriorated even when an image is displayed.

[0008]

In order to achieve the above object, the present invention provides an image data size detection circuit for detecting the size of input image data, and data interpolation for linearly interpolating the number of pixels of a display panel to perform enlargement processing. Matrix, a voltage generation circuit that generates a drive voltage for the display panel, a voltage controller that controls the voltage generation circuit, and a display panel that displays an image, and a dot matrix that automatically changes the brightness It is a display device.

[0009]

According to the present invention, the size of the input image data is detected by the image data size detection circuit, and if the interpolation enlargement processing is necessary, the data interpolation circuit performs the linear interpolation enlargement processing to perform the linear interpolation enlargement processing. If so, the voltage controller controls the voltage generation circuit to automatically change and optimize the brightness of the display panel, and an image with little deterioration in image quality can be obtained.

[0010]

1 is a block diagram showing an embodiment of a dot matrix display device of the present invention. In FIG. 1, 1 is an image data size detection circuit that detects the size of input image data, 2 is a data interpolation circuit that creates linear interpolation data from the input image data, and performs enlargement processing, and 3 is a display that displays an image. Panels 4 and 4 are voltage generation circuits that generate a drive voltage for the display panel 3, and 5 is a voltage controller that controls the voltage generation circuit 4.

In the dot-matrix display device of this embodiment having the above-mentioned configuration, the operation will be described below in the case where a liquid crystal panel is used as the display panel.

The image data size detecting circuit 1 detects the size of the input image data from the horizontal synchronizing signal HD and the vertical synchronizing signal VD of the input image data (m × n dots) and determines the number of pixels of the liquid crystal panel 3 (M × N dots). ) And a control signal indicating whether or not the linear interpolation extension processing is necessary
First, a control signal indicating how high the brightness should be is sent to the voltage controller 4.

When the number of pixels of the liquid crystal panel 3 is equal to (M × N dots), the data interpolation circuit 2 does not perform the linear interpolation expansion process and displays the input image data on the liquid crystal panel 3. If the number of dots of the input image data is different from the number of pixels of the liquid crystal panel, the data interpolation unit 2 creates linear interpolation data from the input image data and enlarges the data into M × N dots. When the M × N dot image data subjected to the interpolation enlargement processing is displayed on the liquid crystal panel 3, the voltage controller 5 receiving the control signal from the image data size detection circuit 1 causes the dynamic range of the drive voltage of the liquid crystal panel 3. Is sent to the voltage generation circuit 4, and the luminance is changed optimally for display.

As an example, the input image data is 640 × 48.
A case will be described where 0 dots or 1024 × 768 dots and the number of pixels of the liquid crystal panel 3 is 1024 × 768 dots.
The image data size detection circuit reads the horizontal synchronizing signal HD and the vertical synchronizing signal VD of the input image data, determines the size of the input image data, and sends a control signal to the data interpolating circuit 2 and the voltage controller 5. Input image data is 1024 ×
In the case of 768 dots, since the number of dots of the input image data is equal to the number of pixels of the liquid crystal panel, the data interpolation circuit 2 displays the liquid crystal panel without performing the linear interpolation enlargement processing.

When the input image data is 640 × 480 dots, the number of dots of the input image data and the number of pixels of the liquid crystal panel are different, so the data interpolation circuit 2 performs the linear interpolation enlargement process. In this case, if the input image data is stored in the memory of the data interpolation circuit 2 and the size is increased 1.6 times in the vertical and horizontal directions, the number of pixels of the liquid crystal panel is reached, and therefore the data interpolation unit 2 operates as shown in FIG. Then, linear interpolation enlargement processing of the input image data is performed and enlargement is performed to a size of 1024 × 768 dots.

If the image is displayed as it is, the deterioration of the image becomes noticeable. Therefore, as shown in FIG. 3, the voltage controller 5 reduces the dynamic range of the driving voltage as the ratio of the number of pixels and the input image data size increases. Sends a control signal to the voltage generation circuit 4, and the voltage generation circuit 4 receiving the signal changes the dynamic range of the drive voltage to optimize the brightness and display it on the liquid crystal panel.

As described above, according to this embodiment, the brightness of the liquid crystal panel is changed depending on the number of dots of the input image data for optimization, so that an image with little deterioration in image quality can be displayed.

Although a liquid crystal panel is used in this embodiment, a similar display device can be constructed by using an EL or plasma display.

[0019]

As described above, according to the present invention,
Even by simply enlarging the input image data by linear interpolation using a simple algorithm, the brightness of the liquid crystal panel is automatically changed to the brightness according to the number of dots of the input image data and optimized, resulting in an image with little deterioration in image quality. The display panel can be fully used for display, and its practical effect is great.

[Brief description of drawings]

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

FIG. 2 is a relationship diagram between input image data and image data after interpolation enlargement processing.

FIG. 3 is a relationship diagram of the ratio of the number of pixels, input image data, and the dynamic range of drive voltage.

[Explanation of symbols]

 1 image data size detection circuit 2 data interpolation circuit 3 liquid crystal panel 4 voltage generator 5 voltage controller

Claims (1)

[Claims] 1. An image data size detection circuit for detecting the size of input image data (m × n dots), a data interpolation circuit for performing linear interpolation enlargement processing on the input image data as necessary, and a pixel for displaying an image. A display panel having a number of M × N dots, a voltage generation circuit that generates a drive voltage for the display panel, and a voltage controller that controls the voltage generation circuit are provided, and the voltage generation is performed according to the size of input image data. A dot matrix display device, wherein a dynamic range of a drive voltage of the display panel generated by a circuit is changed to automatically change the brightness of the display panel.