JPH0719785U - Liquid crystal display - Google Patents

Abstract

(57) [Abstract] [Purpose] When a plurality of liquid crystal panels are arranged side by side to form a display panel, even if the display image is displayed across the joints of the respective liquid crystal panels, the display image is not displayed. It is displayed with the same display width as when it is displayed in the area. [Structure] When an image is displayed in an area of the liquid crystal panel 6 and an image is displayed in the display panel 7, a CGROM is stored in a storage area of the display RAM corresponding to the display area.
In the case where the image data for one image (“B” in this example) stored in is written in a complete form as it is, and the image is displayed across the joint 1a between the liquid crystal panel 6 and the liquid crystal panel 7. Is written in a corresponding storage area in a state in which one column of data is compressed, and the display image is displayed with the same display width as when it is displayed in another area.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a liquid crystal display device.

[0002]

[Prior art]

 Conventional liquid crystal display devices are relatively small and have been used for displays on wristwatches and calculators, but recently there is an increasing demand for large liquid crystal display devices that can also be used as information boards. ing.

However, it is technically difficult to form a large-sized display unit with one liquid crystal panel, and there are many problems to be solved. Therefore, in order to increase the size of the display unit, a plurality of liquid crystal panels must be arranged side by side to form the display unit. However, when arranging the liquid crystal panels in parallel, the pitch between the pixels in the last column of one liquid crystal panel and the pixels in the first column of the liquid crystal panel adjacent to the liquid crystal panel is set to the pixel formed in each liquid crystal panel. It is technically difficult to match the arrangement pitch of the liquid crystal panels, and the pitch between the pixels in the last row of one liquid crystal panel and the pixels in the first row of the liquid crystal panel adjacent to it is formed in each liquid crystal panel. In reality, it is larger than the array pitch of the existing pixels.

[0004]

[Problems to be solved by the device]

 When images and characters are displayed across the pixels in the last column of one liquid crystal panel and the pixels in the first column of the adjacent liquid crystal panel, the images and characters are displayed in one liquid crystal panel. The pixels in the last column of the panel and the pixels in the first column of the liquid crystal panel adjacent thereto are displayed in a state of being largely divided. Therefore, the display width is wider than that of the images and characters displayed in other areas, which causes a problem that the display quality is deteriorated. This problem is especially noticeable in the case of non-flowing character display.

Therefore, an object of the present invention is to display an image, characters, etc. straddling between the pixels in the last column of one liquid crystal panel and the pixels in the first column of the liquid crystal panel adjacent thereto. Even in, the display quality is to be maintained.

[0006]

[Means for Solving the Problems]

 In the liquid crystal display device according to the present invention, a display panel configured by arranging a plurality of liquid crystal panels in which a plurality of pixels are arranged in a matrix and a plurality of image data are stored, and each image is stored. The image data generating means stores the data divided into a plurality of columns, the control circuit for reading the image data to be displayed from the image data generating means, and the storage capacity larger than the display capacity of the display panel. The image data read out from the image data generating means to the control circuit is written via the control circuit, and the image data is divided into columns and stored in the display data storage means and the display data storage means. A driver for driving the display panel based on the image data, and the display panel is a pixel in the last column of one liquid crystal panel and the first column of another liquid crystal panel adjacent to it. The pitch between the pixels is set to twice the arrangement pitch of the pixels of the liquid crystal panel, and the control circuit displays the image data read from the image data generating means in the last row of pixels of one liquid crystal panel and When it does not include the pixels of the first column of another adjacent liquid crystal panel, the image data is written in the display data storage means as the prototype stored in the image data generation means and read out from the image data generation means. When the display area includes pixels in the last column of one liquid crystal panel and pixels in the first column of another liquid crystal panel adjacent thereto, the image data corresponding to one column data from the original pattern stored in the image data generating means. Only the compressed data is written in the display data storage means.

[0007]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 2 shows a drive circuit block diagram of a liquid crystal display device to which the present invention is applied. This liquid crystal display device includes a display panel 1, a central processing unit (hereinafter referred to as "CPU") as a control circuit, and a read-only memory (hereinafter referred to as "CGROM") as image data generating means. 3, a random access memory (hereinafter, referred to as "display RAM") 4 as a display data storage means and a driver 5, which are connected to each other via a data bus.

As shown in FIG. 1, the display panel 1 is configured by arranging two liquid crystal panels 6 and 7 side by side. On the inner surfaces of the transparent substrates 61, 71 of the liquid crystal panels 6, 7, a plurality of transparent scanning electrodes C ₁ , C ₂ , ..., C ₁₀ , C ₁₁ , ... Are formed in the horizontal direction, respectively. On the inner surfaces of the transparent substrates 62 and 72, transparent signal electrodes S ₁ , S ₂ , ..., S ₁₉ , S ₂₀ , S _21, ... Are formed in the vertical direction, respectively. Pixels at the positions where the scanning electrodes C ₁ , C ₂ , ..., C ₁₀ , C ₁₁ , ... And the signal electrodes S ₁ , S ₂ , ..., S ₁₉ , S ₂₀ , S _21, ... 8 are formed, and the pixels 8 are arranged in a matrix on the display panel 1. The pitch P between the pixel 8a in the last column of the liquid crystal panel 6 and the pixel 8b in the first column of the liquid crystal panel 7 that are adjacent to each other via the joint 1a of the liquid crystal panels 6 and 7 is the arrangement pitch of the pixels in each liquid crystal panel. It is twice P ₀ , that is, 2P ₀ .

As shown in FIGS. 3 and 4, three sides of the outer periphery of the liquid crystal panels 6 and 7 are sealed with a sealing material 9 between the opposing transparent substrates. A spacer (not shown) is formed to form a gap in which is sealed. However, the joint surfaces 6a and 7a are coated and sealed with a sealing material 11 that does not contain a spacer, which allows the display portions of the liquid crystal panels 6 and 7 to be arranged close to each other.

FIG. 5 is a flowchart showing an operation of writing the image character data stored in the CGROM 3 shown in FIG. 2 into the display RAM 4 via the CPU 2. According to this flowchart, this liquid crystal display device writes the image data stored in the CGROM 3 into the display RAM 4 via the CPU ₂ and then applies a voltage to the scanning electrodes C ₁ , C ₂ , ... While scanning, a desired image is displayed on the display panel 1 by a so-called dynamic drive system in which image character information is output in parallel to each of the signal electrodes S ₁ , S ₂ , ...

FIG. 6 shows the configuration of the CGROM 3 (see FIG. 2). The storage area of the CGROM 3 is divided by a plurality of columns D ₁ , D ₂ , ... It is divided and stored for each. In the figure, the black part shows the logical value "1", the white part shows the logical value "0", and the symbols D ₁ , D ₂ , ... The values are also shown. FIG. 7 shows the configuration of the display RAM 4, which is a display after the image character data (“B” in this example) to be displayed is read from the CGROM 3 and written in the display RAM 4 (see FIG. 2). The storage state of the image data in the RAM 4 is visually shown. The storage area of the display RAM 4 is divided into columns M ₁ , M ₂ , ... And the image data written from the CGROM 3 via the CPU ₂ is divided into columns and stored. Incidentally, the logical value "1" is part of the black, part of the white is shows the logical value "0", code M _1, M _2, · · · is also the address value of the corresponding column Shows. The columns M ₁ , M ₂ , ... Correspond to the signal electrodes S ₁ , S ₂ , ... Of the display panel 1, respectively, and are stored in the columns M ₁ , M ₂ ,. The stored data are output to the corresponding signal electrodes S ₁ , S ₂ , ... In parallel via the driver 5.

Next, the operation of the liquid crystal display device will be described by taking as an example the case where the display “B B B” is displayed on the display panel 1 as shown in FIG.

In order to display an image on the display panel 1, as described above, it is necessary to first write the image data stored in the CGROM 3 (see FIG. 2) into the display RAM 4 (see FIG. 2). However, when the display area of the image on the display panel 1 is the area of the liquid crystal panel 6, the area extending over the joint 1a between the liquid crystal panel 6 and the liquid crystal panel 7, or the area of the liquid crystal panel 7, Regarding, the operation of writing data to the display RAM 4 is different. Therefore, in the case of displaying in the above-mentioned three display areas, the operation of writing the image data from the CGROM 3 to the display RAM 4 will be described with reference to FIGS. 2, 5, 6 and 7 for each display area.

<Displaying an Image on the Liquid Crystal Panel 6> As described above, the data stored in the columns M ₁ , M ₂ , ... Of the display RAM 4 is transmitted via the driver 5 to the corresponding signal electrodes. The signals are output in parallel to S ₁ , S ₂ , ... Therefore, when displaying an image on the display panel 6, data may be written in the columns M _{1 to} M ₁₉ of the display RAM 4 corresponding to the signal electrodes S _{1 to} S ₁₉ of the liquid crystal panel 6.

Therefore, the writing operation from the CGROM 3 to the display RAM 4 in the case of displaying on the display panel 6 will be described by taking the case of displaying the image “B” in the area of the signal electrodes S _{8 to} S ₁₂ as shown in FIG. 1 as an example. , The operation of writing the image data “B” stored in the columns D _{7 to} D ₁₁ of the CGROM 3 into the columns M _{8 to} M ₁₂ of the display RAM 4 will be described.

First, in step 1, each variable such as the designation of the column address of the CGROM 3 and the designation of the column address of the display RAM 4 is initialized. Next, in step 2, the CPU 2 designates the address of the column of the CGROM 3 as D ₇ which is the lowest address of the columns storing the image data “B”, and the address of the column of the display RAM 4 is set to M ₈ Specify in. Then, in step 3, the column data stored in the column D ₇ in the CGROM 3 is written in the column M ₈ of the display RAM 4. After that, in step 4, the address designation of the column of the CGROM 3 and the address designation of the column of the display RAM 4 are each incremented by one address, and the designated addresses are set to D ₈ and M ₉ , respectively, and the process proceeds to step 5. To do. In step 5, it is determined whether or not the address M _n of the column of the display RAM 4 incremented in step 4 is M ₂₀ , that is, n = 20. Note that M ₂₀ is the address of the column corresponding to the signal electrode S ₂₀ in the first column of the liquid crystal panel 7 in the display panel 1.

In this case, since M _n = M ₉ , the determination is NO, and step 6 is skipped and the process proceeds to step 7. Then, in step 7, it is determined whether or not all the image data “B” data stored in the CGROM 3 has been written in the display RAM 4. In this case, the data written in the display RAM 4 is only the data stored in D ₇ , so the determination is NO, the process proceeds to step 3, and the operation of writing the data of D ₈ to M ₉ is started. To be done.

In this way, the data of D _{7 to} D ₁₁ are sequentially written to M _{8 to} M ₁₂ , but since all of M _{8 to} M ₁₂ are lower addresses than M ₂₀ , the process proceeds to step 5. All judgments are NO. Therefore, step 6 is skipped and steps 3, 4, 5 are repeated until all the column data of the image data “B” stored in D _{7 to} D ₁₁ are written in M _{8 to} M ₁₂ of the display RAM 4. Go around the routine of 7. When the transfer of the data of D ₁₁ to M ₁₂ is completed and the transfer of the data of image data “B” is completed, the images of CGROM 3 are displayed in M _{8 to} M ₁₂ of the display RAM 4 as shown in FIG. The data "B" is stored in its complete form. After that, the determination in step 7 is YES, the process proceeds to step 1 and the address designation of the columns of the CGROM 3 and the display RAM 4 is initialized.

<When Displaying an Image Across the Seam 1a between the Liquid Crystal Panel 6 and the Liquid Crystal Panel 7> In this case, the image display area is a seam 1a between the liquid crystal panel 6 and the liquid crystal panel 7 (shown in FIG. 1). ) Is a region including signal electrodes S ₁₉ and S ₂₀ adjacent to each other. Therefore, the data write destination in the display RAM 4 in this case is an area including the columns M ₁₉ , M ₂₀ corresponding to the signal electrodes S ₁₉ , S ₂₀ of the liquid crystal panels 6, 7. Its In no event to display the image "B" as shown in FIG. 1 in this in the area of the signal electrodes S ₁₈ to S _21, the image data "B" stored in the column D ₇ to D ₁₁ of CGROM3 The operation of writing in the columns M _{18 to} M ₂₁ of the display RAM 4 will be described as an example.

The case of writing the data of D ₇ and D ₈ into M ₁₈ and M ₁₉ is the same as the case of writing into the above M _{8 to} M ₁₂ . However, after writing the data of D ₈ to M ₁₉ , in step 4, when the address designation of the columns of the CGROM 3 and the display RAM 4 is incremented by 1 address respectively, and D ₉ and M ₂₀ are obtained, n = 20. The determination in step 5 is YES. Therefore, M ₈ ~ M
Unlike the case of storing in step ₁₂ , step 6 is skipped and step 6 is performed. Then, in step 6, the address D ₉ of the column of the CGROM 3 is further incremented by 1 address to become D ₁₀ . After that, the process proceeds to step 7. However, at this point, the writing of the image data “B” has not been completed, so the determination in step 7 is NO. Then, the process proceeds to step 3, and the data of D ₁₀ is written in M ₂₀ . Then, in step 4, the address of the column and column is incremented by one address to become D ₁₁ and M ₂₁ , respectively. Then, the determination in step 5 becomes NO again, step 6 is skipped, and the process proceeds to step 7. Then, when step 3 is reached again, the column data of D ₁₁ is written in M _21, and the writing of the image data “B” is completed. Then, the process proceeds to steps 4 and 5 again, and when the process reaches step 7, the determination in step 7 becomes YES, the process proceeds to step 1 and the address designation of each column is initialized.

As a result, among the data stored in D _{7 to} D ₁₁ (FIG. 6), the data stored in D ₉ is not written in M _{18 to} M ₂₁ as shown in FIG. The image data for the image is written in a state of being compressed by one column.

<When Displaying Image on Display Panel 7> In this case, the data write destination in the display RAM 4 is the columns M _{20 to} M ₃₈ corresponding to the signal electrodes S _{20 to} S ₃₈ of the liquid crystal panel 7. Therefore, as shown in FIG. 1, the image data “B” stored in the columns D _{7 to} D ₁₁ of the CGRO M3 is taken as an example of displaying the image “B” in the regions of the signal electrodes S _{27 to} S _31. describing the operation that will be written ₃ to the co-ram M ₂₇ ~M ₃₁ of display RAM4.

In this case, M _{27 to} M ₃₁ all have address values larger than M ₂₀ . Therefore when and writes the sequential M ₂₇ ~M ₃₁ the data stored in the D ₇ to D _11, the determination in Step 5 in each of the write operation are all NO. Therefore, the writing operation is performed in the same manner as in the case where the column addresses of the CGROM 3 and the display RAM 4 are designated in D ₇ and M ₂₇ in step 2, and then the writing is performed in M _{8 to} M ₁₂ described above. , 7 is performed by a routine. Then, after the writing of the data of D ₁₁ to M ₃₁ is completed and the writing of the image data “B” is completed, the process proceeds from step 7 to step 1 and the address designation of each column is initialized. It Note that the M ₂₇ ~M _31, written remains complete form of image data stored in the D ₇ to D ₁₁ as if writing to M ₈ ~M ₁₂ the aforementioned prototype.

As described above, in the display panel 1, <when displaying an image on the liquid crystal panel 6>, <when displaying across the joint 1a between the liquid crystal panel 6 and the liquid crystal panel 7>, <when the image is displayed on the display panel 7 In the case of displaying>, it is the operation of writing the CGROM3 image data “B” in the display RAM 4.

Then, as shown in FIG. 7, in <displaying an image on the liquid crystal panel 6> and <displaying an image on the display panel 7>, a storage area in the display RAM 4 corresponding to the display area is displayed. The image data for one image (“B” in this example) stored in the CGROM 3 is written in its original form in perfect form, and <the image is displayed across the joint 1a between the liquid crystal panel 6 and the liquid crystal panel 7. If yes>, one column of data is written in a compressed state in the corresponding storage area.

Thereafter, the driver 5 dynamically drives the scan electrodes C ₁ , C ₂ ... To apply a predetermined voltage to the scan electrodes, and scan the columns M _{8 to} M ₁₂ , M _{18 to} M ₂₁ , and M _{27 to} M _31. each image data "B" stored, the signal electrodes S ₈ to S ₁₂ corresponding respectively Display panel 1 for each _{data, S 18 ~S 21, S 27} ~S 31 parallel outputs to the. By the above operation, the display image “B B B” can be displayed on the display panel 1, and at this time, the display image (“B” in this example) is displayed on the liquid crystal through the joint 1a as shown in FIG. Even when it is displayed across the pixels 8a in the last column of the panel 6 and the pixels 8b in the first column of the liquid crystal panel 7, the display width of the display image is the same as that in the other area. Can be displayed with.

[0027]

[Effect of device]

 As described in detail above, according to the liquid crystal display device of the present invention, when a plurality of liquid crystal panels are arranged side by side to form a display panel, the display image is displayed across the joints of the respective liquid crystal panels. Even when it is displayed, the display image can be displayed with the same display width as when it is displayed in another area, so that it is possible to maintain the desired display quality and hinder the legibility of characters. Never.

[Brief description of drawings]

FIG. 1 is a front view of a display panel of a liquid crystal display device to which the present invention is applied.

FIG. 2 is a block diagram of a drive circuit of a display panel.

FIG. 3 is a front view showing the internal structure of the display panel with a part thereof cut away.

FIG. 4 is an enlarged cross-sectional view of a display panel.

FIG. 5 is a flowchart showing a write operation to display data storage means.

FIG. 6 is an explanatory diagram of a configuration of image data generating means.

FIG. 7 is an explanatory diagram of a configuration of display data storage means.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 display panel 1a joint 2 central processing unit (control circuit) 3 CGROM (image data generator) 4 display RAM (display data storage means) 5 driver 6,7 liquid crystal panel 8 pixels 8a last row pixel 8b first row pixel

Claims (1)

[Scope of utility model registration request] 1. A display panel configured by juxtaposing a plurality of liquid crystal panels in which a plurality of pixels are arranged in a matrix, and a plurality of image data are stored. Image data generating means divided into columns and stored, a control circuit for reading out the image data to be displayed from the image data generating means, and a storage capacity larger than the display capacity of the display panel, The image data read from the image data generating means to the control circuit is written via the control circuit, and is also written to the display data storage means for dividing and storing the image data in columns. And a driver for driving the display panel based on the image data, wherein the display panel includes a pixel in the last column of one liquid crystal panel and The pitch between the adjacent pixels of the first column of the liquid crystal panel is set to be twice the arrangement pitch of the pixels, and the control circuit controls the image data read from the image data generating means. When the display area does not include the pixels in the final column and the pixels in the first column, the image data is written in the display data storage means as it is in the prototype stored in the image data generation means, and the image data generation is performed. When the display area of the image data read from the means includes the pixels in the last column and the pixels in the first column, the image data is compressed by one column data from the prototype stored in the image data generating means. A liquid crystal display device, characterized in that the liquid crystal display device is written in the display data storage means in the above state.