KR100977228B1 - Liquid Crystal Display Device - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device having an optical touch sensor function used in a car navigation system and the like, and more particularly, to a liquid crystal display device capable of inputting a touch position with high accuracy.

A liquid crystal display device according to the present invention is a liquid crystal display device having an optical touch sensor function.

A transparent substrate having a plurality of dot electrodes corresponding to the display screen, a plurality of photosensors provided on the transparent substrate so as to be adjacent to at least one of the plurality of dot electrodes, and a gate for individually driving the plurality of dot electrodes Display driving control means for driving a plurality of dot electrodes by controlling a line and a source line, a sensor output line for outputting a sensor output signal from the plurality of photosensors, an applied voltage applied to the gate line and the source line; And a touch position recognition means for recognizing a touch position on the transparent substrate based on the sensor output signals output from the plurality of photosensors, wherein the display drive control means includes a recognition position recognized by the touch position recognition means. It characterized in that it comprises a cursor display control means for displaying a cursor on.

Touch, cursor, sensor

Description

Liquid crystal display device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device having an optical touch sensor function used in a car navigation system and the like, and more particularly, to a liquid crystal display device capable of inputting a touch position with high accuracy.

A liquid crystal display device having an optical touch sensor function has a plurality of photo sensors provided to correspond to each pixel on a transparent substrate, and attention is applied to a car navigation system or the like. (For example, Japanese Patent Laid-Open No. 2000-172444). Reference)

FIG. 5 is an external view showing a liquid crystal display device 10A having a general optical touch sensor function applied to a car navigation system.

Although not shown, the liquid crystal display device 10A includes a display driving controller, a sensor output signal processor, and the like.

As shown in Fig. 5, when a user's finger is placed on the screen of the liquid crystal display device 10A, the sensor output signal outputted from the touch position photosensor (not shown) is blocked due to the blocking of ambient light or reflection of the display light. The output level is changed, and the touch position can be recognized based on the region in which the sensor output signal is changed.

However, as is well known, since the recognition performance as the optical touch sensor is not so high in the liquid crystal display device 10A, there is a problem that an error tends to occur when recognizing the contact or the position coordinate.

That is, because a subtle difference occurs between the touch position intended by the operator and the recognition position of the actual finger, there is a possibility that a selection item on the menu screen intended by the operator is incorrectly input, for example.

In the conventional liquid crystal display device, since a subtle difference occurs between the touch position intended by the operator and the detected position of the actual finger, the touch position intended by the operator is different from the recognized detection position, and is input as a touch sensor. There was a problem that the precision was lowered.

SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid crystal display device which improves the input accuracy of a touch position by displaying a cursor at a recognition position with a touch position including a position close to an operator's finger to solve the above problems. It is done.

In order to achieve the above object, the liquid crystal display device according to the present invention, in the liquid crystal display device having an optical touch sensor function,

A transparent substrate having a plurality of dot electrodes corresponding to the display screen, a plurality of photosensors provided on the transparent substrate so as to be adjacent to at least one of the plurality of dot electrodes, and a gate for individually driving the plurality of dot electrodes Display driving control means for driving a plurality of dot electrodes by controlling a line and a source line, a sensor output line for outputting a sensor output signal from the plurality of photosensors, an applied voltage applied to the gate line and the source line; And a touch position recognition means for recognizing the touch position on the transparent substrate based on the sensor output signals output from the plurality of photosensors.

The display drive control means is characterized in that it comprises a cursor display control means for displaying the cursor at the recognition position recognized by the touch position recognition means.

According to the present invention, since the operator can perform the input operation while checking the actual recognition position of the finger with the cursor, it is possible for the operator to easily supplement the input operation in real time. It is possible to improve the input precision of the touch position to avoid the input.

Hereinafter, specific embodiments will be described in more detail for the practice of the present invention.

[First Embodiment]

Hereinafter, a first embodiment of the present invention will be described with reference to the accompanying drawings.

1 is a side sectional view showing a liquid crystal display device having an optical touch sensor function with a control device according to a first embodiment of the present invention.

FIG. 2 is a plan view showing the configuration of the transparent substrate portion (glass substrate portion) in FIG. 1, and schematically shows an enlarged signal line and related specific electrode configurations.

As shown in Fig. 1, the liquid crystal display device 10A having an optical touch sensor function is provided with two transparent substrates 11 constituting a display panel interposed with liquid crystal and light (dashed arrows) from the back side of the transparent substrate 11. A plurality of photosensors (hereinafter simply referred to as 'sensors') 13 interposed between the backlight 12 for irradiating the light and the two transparent substrates 11, the display driving control unit 21 and the touch. The control apparatus 20 which has the position recognition part 22 is provided.

The display drive control unit 21 includes a cursor display control unit 23 in which a cursor to be described later is displayed at a recognition position according to the touch position recognition 22.

In addition, the touch position recognition unit 22 has a function of recognizing the touch position or the touch proximity position of the finger 30 based on the sensor output signal, and includes the distance discrimination unit 24. The distance discrimination unit 24 determines the distance between the transparent substrate 11 and the operator's finger 30 based on the sensor output signal.

As shown, when the operator places the finger 30 on the display panel of the liquid crystal display device 10 having the optical touch sensor function, the surroundings incident on the sensor 13 in the area corresponding to the touch position. Light, that is, light incident to the photosensor from the surroundings (see dashed-dotted arrow) is blocked, or light from the backlight 12 (see dashed line arrow) is reflected and incident on the sensor 13.

In this way, the level of the sensor output signal in the area corresponding to the touch position is significantly changed compared with the level of other sensor output signals, and the change of the sensor output signal level is caused by the touch position recognition unit ( 22).

As shown in Fig. 2, the transparent substrate 11 has a plurality of gate electrodes 14 (14b, 14r, 14g) corresponding to each of the display pixels of B (blue), R (red), and G (green). Each gate electrode 14 is sequentially arranged in the line (middle-right side) direction of a display screen.

In addition, the plurality of sensors 13 are individually provided in the transparent substrate 11 so as to be adjacent to at least one of the plurality of gate electrodes 14.

The gate lines Gn + 1, Gn + 2,... Are signal lines for driving each gate electrode individually to the plurality of gate electrodes 14. And B source lines Sb, R source lines Sr, and G source lines Sg orthogonally arranged to each gate line Gn + 1, Gn + 2, ..., and the like.

Each sensor 13 is connected with a sensor output line RO for reading and outputting a sensor output signal from each sensor 13.

The gate lines Gn + 1, Gn + 2, ..., and the source lines Sb, Sr, Sg are drive controlled by the display drive controller 21 in the control device 20 in response to the display data.

The display drive control unit 21 controls the applied voltages to the gate lines Gn + 1, Gn + 2, ..., and the source lines Sb, Sr, Sg to drive the plurality of gate electrodes 14.

The sensor output line RO is input to the touch position recognition unit 22 in the control device 20.

The touch position recognition part 22 draws the area | region which shows the variation amount of a sensor output signal more than a threshold, for example based on the sensor output signal from the some sensor 13, The transparent substrate 11 Recognize the touch position on the image.

The cursor display control unit 23 in the display drive control unit 21 is configured to display the cursor 31 (see FIGS. 3A and 3B) at the recognition position by the touch position recognition unit 22, and the operator's finger ( Accompanied by the movement of 30, the cursor 31 is moved.

3A and 3B show a state in which the cursor 31 is displayed according to the distance between the finger 30 and the screen in the liquid crystal display according to the first embodiment of the present invention.

3A and 3B, the liquid crystal display device 10 having the glass substrate 40 includes the display drive controller 21 (see FIG. 1), the source IC 41 and the gate IC 42, and the touch position recognition. The part 22, the output IC 43, and the flexible printed circuit board 44 with the wiring connected to each IC 41-43 etc. are included.

The source IC 41 includes a B source line Sb, an R source line Sr, and a G source line Sg (see Fig. 2). The gate IC 42 includes a gate line Gn + 1. , Gn + 2, ...).

The output IC 43 also includes a sensor output line RO.

The touch position recognition unit 22 includes a distance discrimination unit 24 for determining a distance between the transparent substrate 11 and the operator's finger 30 based on the sensor output signal, and the display driving control unit 21 The display size of the cursor 31 is changed in response to the determination result of the distance discriminating unit 24.

Specifically, the closer the finger 30 of the operator to the transparent substrate 11, i.e., the closer the distance determined by the distance discriminating part 24 is, the larger the cursor 31 is. Make it easy for the operator to confirm the decision position.

In addition, the touch position recognizing unit 22 is present in a predetermined area when the cursor display has a predetermined size or more, ie, when the finger 30 contacts the transparent substrate 11 based on the sensor output signal. When is continued for a predetermined time or longer, i.e., when the time for stopping to the operator's intended selection position continues for a predetermined time or longer, the cursor 31 is recognized as the operation determination position.

Next, referring to the flow chart of FIG. 4, the processing operation of the touch position recognition unit 22 according to the first embodiment of the present invention will be described.

As shown in Fig. 4, the touch position recognizing unit 22 performs image correction processing (steps 10 and S10) on the input image based on the sensor output signal, and then steps 21 to 23 (S21 to S23). An image analysis process (steps 20 and 20) is executed.

More specifically, in the image correction processing (steps 10 and 10), the normalization operation and the noise removing operation for the input image are performed.

Through luminance normalization, since the average luminance of one screen is, for example, 512 levels, subsequent image processing is stabilized. In addition, analysis accuracy may be improved by removing noise.

In this manner, after the image correction process is performed, the image analysis process (steps 20 and S20) is performed.

In more detail, the image analysis processing (steps 20 and S20) operation obtains a threshold value from the histogram of the image (steps 21 and S21), performs image rendering (steps 22 and S22) according to the threshold value, and then Find the center (Step 23, S23)

The threshold means a luminance that can divide a shadow of a finger and a background, that is, a minimum physical quantity causing an electrical reaction.

For example, it may be obtained from the upper and lower ends of the luminance average of all pixels and the histogram of the histogram of the image. That is, after setting the parameters col and cod for the top and bottom, excluding the (total number of pixels) / col number of pixels from the brightest pixels, set the brightest luminance to the top, and from the darkest pixels (total number of pixels). After excluding the number of) / cod pixels, the darkest luminance may be set to the bottom, and then the threshold may be obtained according to the following equation.

(Threshold) = [bottom + {average-(top-average)}] / 2 = mean-(top-bottom) / 2

Alternatively, the threshold may be obtained by using the kittler method. In this case, it can be an effective method when the area ratio of the part (the shadow of the finger) to be separated from the background is large.

In this way, after the threshold is obtained, an image regarded as a shadow is drawn according to the threshold, and then the center of the image regarded as the shadow is obtained.

The process of finding the center may be obtained by, for example, assigning a weight value to each pixel according to the luminance of each pixel in a pixel regarded as a shadow, and then using a weighted average of all pixels.

That is, the x coordinate cx of the center and the y coordinate cy of the center may be obtained through the following equations, respectively.

(∑ is the total of all pixels, x [p] and y [p] are the x and y coordinates of each pixel, w [p] is the weight of each pixel, and wsum is the sum of the weights of all pixels. do.)

Further, the distance discrimination unit 24 in the touch position recognition unit 22 is transparent to the finger 30 at the touch position (including the proximity position) from the size of the rendered image with respect to the step 22 (S22). The distance between the substrates 11 is determined.

In this way, the cursor display control unit 23 in the display drive control unit 21 causes the cursor 31 to be enlarged and displayed as long as the distance from the finger 30 is close in response to the determination result by the distance discriminating unit 24. It is possible.

In addition, the touch position recognizing unit 22 has the cursor display having a predetermined size or more based on the sensor output signal, and the position of the cursor 31 when the state existing within the predetermined range is maintained for a predetermined time or longer. Is recognized as the operation determination position, that is, the touch position.

As described above, the liquid crystal display device 10 having the optical touch sensor function according to the first embodiment of the present invention includes a transparent substrate 11 having a plurality of dot electrodes 14 corresponding to a display screen, A plurality of sensors 13 disposed on the transparent substrate 11 adjacent to at least one of the dot electrodes 14 and gate lines Gn + 1 and Gn + 2 for individually driving the plurality of dot electrodes 14. , ...) and source lines (Sb, Sr, Sg), sensor output lines (RO) for reading and outputting sensor output signals from the plurality of sensors (13), and applied voltages of the gate lines and source lines to control the plurality of The display driving control unit 21 for driving the gate electrode 14 of the sensor and the touch position recognition unit 22 for recognizing the touch position on the transparent substrate 11 based on the sensor output signals from the plurality of sensors 13. Equipped,

The display drive control unit 21 includes a cursor display control unit 23 for displaying the cursor 31 at a position recognized by the touch position recognition unit 22.

Thus, with respect to the liquid crystal display device 10 incorporating an optical touch sensor, the operator can instruct the selection position while visually looking at the cursor 31 following the movement of the finger 30, thus recognizing performance. In addition, it is possible to avoid mis-input and improve the input accuracy.

Further, since the cursor 31 is enlarged and displayed as the finger 30 approaches the panel of the liquid crystal display device 10, the operator can easily and surely confirm the final operation position (selection position). .

That is, the cursor 31 is driven by the movement of the finger 30, and moves along with the finger 30 to the panel so that the cursor 31 follows the enlarged display so that the operator can correct the coordinates of the touch sensor and recognize the touch (click). It is possible to easily carry out.

In addition, the touch position recognition unit 22, when the cursor 31 reaches a predetermined size or more, and exists over a predetermined time or more within a predetermined range (constant coordinate area), the touch position (operation) of the operator Position).

The present invention described above is not limited to the above-described embodiments and the accompanying drawings, and it is common in the art that various substitutions, modifications, and changes can be made without departing from the technical spirit of the present invention. It will be evident to those who have knowledge of.

1 is a side sectional view showing a liquid crystal display and a control device together according to a first embodiment of the present invention;

FIG. 2 is a plan view schematically showing a specific configuration of the transparent substrate in FIG.

3A and 3B are explanatory diagrams showing size manipulation states of and cursors according to touch positions in the liquid crystal display according to the first embodiment of the present invention;

4 is a flowchart showing the operation of the touch position recognition unit according to the first embodiment of the present invention.

5 is an external view showing a liquid crystal display having a general optical touch sensor function.

<Brief description of reference numerals>

10 liquid crystal display device 11 transparent substrate

12 Backlight 13 Sensor (Photo sensor)

14, 14b, 14r, 14g: gate electrode 20: control device

21: display drive control unit 22: touch position recognition unit

23: cursor display control unit 24: distance discrimination unit

30: operator's finger 31: cursor

Gn + 1, Gn + 2, ...: gate lines Sb, Sr, Sg: source lines

RO: Sensor output line

Claims (3)

In the liquid crystal display device having an optical touch sensor function, A transparent substrate having a plurality of dot electrodes corresponding to the display screen; A plurality of photosensors provided on the transparent substrate to be adjacent to at least one of the plurality of dot electrodes; A gate line and a source line for individually driving the plurality of dot electrodes; A sensor output line for outputting sensor output signals from the photosensors; Display driving control means for controlling the voltage applied to the gate line and the source line to drive the plurality of dot electrodes; And A touch position recognizing means comprising a distance discrimination means for recognizing a touch position on the transparent substrate based on sensor output signals output from the plurality of photosensors and for determining a distance between the transparent substrate and a finger of an operator; In the liquid crystal display device having an optical touch sensor function, The display drive control means includes cursor display control means for displaying a cursor at a recognition position recognized by the touch position recognition means, And the cursor display control means enlarges the cursor display size as the distance determined by the distance discriminating means approaches in response to the determination result by the touch position recognizing means. delete The method of claim 1, And the touch position recognizing means recognizes the position of the cursor as an operation determination position when the cursor position continues for a predetermined time or more within the touch area.

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