KR20070001414A - Method and display device for controlling viewing angle by recognizing location of user - Google Patents

Abstract

A method for controlling a viewing angle by recognizing a user's position and a display apparatus are provided to prevent the opening of a screen. A viewing angle control menu is selected through the manipulation of a key input member(S210). A camera is driven(S220) and an object is outputted on the liquid crystal display member. A user confirms the message outputted on the LCD(Liquid Crystal Display) screen display member and the photographing is performed at the photographing position and angle thorough the manipulation of the key input member(S230). A specific portion of a user face from the photographed image is recognized(S240). A microprocessor calculates a photographed angle by calculating an angle between eyes and the camera and also calculates a correction viewing angle by means of the photographed angle(S250).

Description

Method and display device for controlling viewing angle by recognizing location of user}

1 is a block diagram schematically illustrating a mobile communication terminal having a display device for controlling a viewing angle by recognizing a location of a user according to an exemplary embodiment of the present invention;

2 is a flowchart illustrating a method of controlling a viewing angle by recognizing a location of a user according to an exemplary embodiment of the present invention;

3 is an exemplary diagram for explaining a method of calculating a photographing angle and a corrected viewing angle according to a preferred embodiment of the present invention.

<Description of Symbols for Main Parts of Drawings>

110: microprocessor 120: memory

130: key input unit 140: liquid crystal screen display unit

150: camera unit 310, 320: eye coordinate value

330: average coordinate value

The present invention relates to a display device for controlling a viewing angle by recognizing a location of a user. In more detail, after photographing the user using the provided camera, the user recognizes a specific part of the user's face from the photographed image, checks the degree of deviation between the camera and the specific part, and controls the viewing angle of the display device according to the degree. A display device for controlling a viewing angle by recognizing a location of a user.

Recently used mobile communication terminals such as CDMA (Code Division Multiple Access) 2000 phones, IMT-2000 phones, etc. are attached to the camera as an additional device for implementing image capture and transmission, real-time video communication. Such cameras have been developed in a variety of ways, such as detachable using a jack, a type embedded in a terminal body.

In addition, the recent mobile communication terminal may output in the form of black and white or color to the liquid crystal display device provided with a variety of information, such as image, multimedia video, background content in addition to the camera function described above.

On the other hand, a liquid crystal display (LCD) is mainly used as a display device provided in the mobile communication terminal. Such liquid crystal display devices are not only mobile communication terminals, but also display devices that are recently used in various fields such as digital cameras, notebook computers, and TVs. The liquid crystal display device has a low operating voltage, low power consumption, small size, and light weight, and thus is a convenient device that is frequently used in portable devices.

However, the liquid crystal display device has a structure in which the light of the back light passes through the liquid crystal layer and the color filter to show color to our eyes, and thus the viewing angle is limited compared to a self-luminous display device such as a CRT monitor.

Here, the viewing angle is a numerical value indicating whether the monitor is different from the normal view when the monitor is viewed obliquely at the positions of up, down, left and right. For example, a horizontal viewing angle of 170 degrees means that viewing at a position of 85 degrees to the left and 85 degrees to the right is acceptable. However, since the display standard of the viewing angle is the angle at which the contrast ratio is 10: 1, the decrease in luminance and discoloration occurs in the eyes, and thus, the viewing angle in manufacturing and the viewing angle in manufacturing are different.

Therefore, the mobile communication terminal equipped with the liquid crystal display device should be able to adjust the viewing angle so that the viewing angle is limited than the conventional monitor so that the user can see and recognize the output of the liquid crystal display device. In addition, by using the viewing angle characteristic of the liquid crystal display device, it is possible to increase the security by preventing others from viewing the contents output to the liquid crystal display device from side or top and bottom.

On the other hand, in order to overcome the narrow viewing angle of the liquid crystal display device has recently been developed a technology for making the viewing angle of the liquid crystal display device by adding a second panel for changing the viewing angle on the panel of the liquid crystal display device.

This technology adjusts the viewing angle by turning on / off the viewing angle changing panel.When the viewing angle changing panel is off, the viewing angle of the lower panel is used as it is.When turning on the viewing angle changing panel, the viewing angle of the lower panel is restricted and overall. It is a technique to have two viewing angles.

However, this technology can only adjust the viewing angle to only two viewing angles, the left and right and the viewing angles are equally adjustable. In other words, when the viewing angle changing panel is off, the left and right viewing angles are 80 °, respectively, when the viewing angle changing panel is turned on, the left and right viewing angles are reduced to 40 °, so that the fluctuations of the left and right and the upper and lower viewing angles are the same. As a result, when the user views the LCD screen at an angle and does not look at the front side, a difference occurs in the screen seen by the left eye and the right eye, causing eye fatigue.

In addition, this technique does not completely solve the inconvenience that the user experiences due to the viewing angle because the user does not consider the exact angle at which the actual user views the liquid crystal display as the user arbitrarily adjusts the viewing angle.

In order to solve this problem, the present invention, after photographing the user using the provided camera, recognizes a specific portion of the user's face from the photographed image to determine the degree of deviation between the camera and the specific region, Accordingly, an object of the present invention is to provide a method and a display device for controlling a viewing angle by recognizing a location of a user who controls a viewing angle of a display device.

In order to achieve the above object, the present invention provides a memory unit for storing data, a camera unit for photographing a subject to generate an image, a key input unit for receiving keys, a liquid crystal screen display unit for outputting a screen, and a memory unit, a camera unit, and an input unit. A method of controlling a viewing angle of a screen by recognizing a user's position in a display device including a microprocessor for controlling a liquid crystal display, the method comprising: (a) driving a camera unit to photograph a subject and generate a photographed image; ; (b) comparing the image with a stored image previously stored in the memory unit to recognize a specific portion of the image; (c) calculating a corrected viewing angle by calculating a photographing angle with a specific portion; And (d) transferring the corrected viewing angle to the liquid crystal display, thereby controlling the liquid crystal display to output the screen at the corrected viewing angle.

In addition, according to another object of the present invention, a display device for outputting a screen by controlling the viewing angle, comprising: a key input unit for receiving a key from a user; A camera unit for photographing a user and generating a photographed image; A memory unit configured to drive a display device and to store a plurality of software for performing additional functions, a viewing angle adjustment software for adjusting a viewing angle, and a storage image which is a user image photographed by a camera unit and an image of a shape of a specific portion; A liquid crystal display including a liquid crystal panel and a driving power supply and outputting a screen by adjusting a viewing angle according to an input control signal; And analyzing the kit value input from the user and executing the viewing angle adjusting software to control the camera unit according to a predetermined algorithm of the viewing angle adjusting software to photograph the user, compare the photographed image with the stored image, and recognize a specific portion, After calculating the corrected viewing angle by calculating the photographing angle, the display device for controlling the viewing angle by recognizing the user's position including a microprocessor for controlling the liquid crystal display to output the screen to the corrected viewing angle.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are designated as much as possible even if displayed on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted.

1 is a block diagram schematically illustrating a mobile communication terminal having a display device for controlling a viewing angle by recognizing a location of a user according to an exemplary embodiment of the present invention.

A mobile communication terminal having a display device for controlling a viewing angle by recognizing a user's position according to an exemplary embodiment of the present invention includes a microprocessor 110, a memory unit 120, a key input unit 130, and a liquid crystal display unit 140. ) And a camera unit 150.

The microprocessor 110 controls the overall operation of the mobile communication terminal. In addition, the microprocessor 110 executes various applications stored in the memory unit 120 according to a signal input from the key input unit 130. In addition, the microprocessor 208 controls to transmit and store the data to the memory unit 120 when data that is not immediately executed is input.

The microprocessor 110 according to an exemplary embodiment of the present invention analyzes a signal received from the key input unit 130 when the user manipulates the key input unit 130 to adjust the viewing angle of the liquid crystal display 140. After executing the viewing angle adjustment software stored in the unit 120, and controlling the camera unit 150 according to a predetermined algorithm of the viewing angle adjustment software to capture the user, the shape of the specific region previously stored in the memory unit 120 Recognizes a specific part of the user by comparing with a stored image, which is an image of a, and calculates a photographing angle, which is an angle between the camera and the specific part, calculates a corrected viewing angle, which is to be corrected, and then supplies it to the liquid crystal display 140. The voltage is set and supplied according to the corrected viewing angle to control the liquid crystal display to output at the corrected viewing angle.

The memory unit 120 stores a plurality of applications for driving the mobile communication terminal and performing various additional functions. To this end, the memory unit 120 may electrically modify the contents in units of EEPROM (Block) or blocks in which the contents may be modified in units of bytes, which are nonvolatile memories. ) And SDRAM (Synchronous Dynamic Random Access Memory).

In addition, the memory unit 120 according to a preferred embodiment of the present invention stores the viewing angle adjustment software executed by the microprocessor 110, and stores a stored image to be compared with the image of the photographed user.

The key input unit 130 includes a number button for inputting a number such as a phone number, a letter button for inputting a character, a menu selection button, and the like. The key input unit 204 receives a menu key for adjusting the viewing angle and a selection key for adjusting the viewing angle according to a user's selection.

The liquid crystal display 140 displays an operation state of the terminal, including a power supply state, a reception intensity of radio waves, a date and time, and when the information is transmitted in the form of text, the user displays the information on the liquid crystal display. Make sure you have the information you need.

In addition, the LCD screen 140 according to the preferred embodiment of the present invention adjusts the viewing angle of the screen output under the control of the microprocessor 110. That is, the liquid crystal display 140 may increase the transmission intensity at the oblique viewing angle to enhance the white phenomenon or the gray scale inversion phenomenon, thereby achieving narrow viewing angle characterization, and reduce the transmission intensity at the oblique viewing angle to weaken the white phenomenon and gray scale inversion phenomenon. To achieve wide viewing angle characterization.

To this end, the liquid crystal display 140 according to the preferred embodiment of the present invention has a display characteristic in which the transmittance of the tilted viewing angle is greater than the transmittance of the front when the front transmittance of the liquid crystal display and the transmittance of the tilted viewing angle are set to 1, respectively. A liquid crystal panel and a drive voltage setting part which sets the drive voltage which drives a liquid crystal panel, and supplies the drive voltage set with respect to the said liquid crystal panel are provided. Here, the driving voltage setting unit sets the driving voltage according to the corrected viewing angle received from the microprocessor 110 to control the viewing angle characteristic.

According to the configuration of the liquid crystal screen display unit 140, since the driving voltage according to the corrected viewing angle characteristic is supplied to the liquid crystal panel, the transmission intensity determined by the driving voltage is also based on the corrected viewing angle characteristic, whereby the liquid crystal By simply setting the drive voltage supplied to a panel according to viewing angle characteristic, it becomes possible to switch to the viewing angle in which the viewing angle in a liquid crystal panel was corrected.

The camera unit 150 generates an optical signal corresponding to the captured image by photographing a subject under the control of the microprocessor 110, converts the optical signal into image data that is an image signal, and transmits the optical signal to the microprocessor 110. Create a captured image.

2 is a flowchart illustrating a method of controlling a viewing angle by recognizing a location of a user according to an exemplary embodiment of the present invention.

A user needs to photograph a camera created in a mobile communication terminal at an oblique angle, not in front of himself or herself, in order to photograph a person or object around him or herself with a specific object. At this time, the user needs to adjust the camera angle while taking a picture while viewing the screen output on the LCD screen 140 while taking a picture.

However, the liquid crystal display 140 mounted on the mobile communication terminal has a limited viewing angle, and when viewed at an oblique angle from the side, a white phenomenon or a gray scale deformation (inversion) phenomenon occurs, and it is difficult for a user to check a proper image. In this case, the user may see a clear screen from the top, bottom, left, and right sides by adjusting the viewing angle of the LCD screen 140.

In order to adjust the viewing angle of the liquid crystal display 140, the user operates the key input unit 130 of the mobile communication terminal to select a viewing angle adjusting menu (S210).

When the microprocessor 110 of the mobile communication terminal receives a key input signal according to the viewing angle adjustment menu selection from the key input unit 130, the microprocessor 110 reads and executes the viewing angle adjustment software stored in the memory unit 120. The executed viewing angle adjusting software switches the mobile communication terminal to a shooting mode according to a predetermined algorithm, drives the camera unit 150 (S220), and outputs the subject to the liquid crystal display 140. In this case, the mobile communication terminal may output a message "Please take a picture for viewing angle adjustment" on the liquid crystal display (140), and allow the user to photograph the user at an angle to be photographed.

That is, the present invention allows the user to photograph the user at a photographing angle (without adjusting the viewing angle of the liquid crystal display 140), and recognizes a specific part of the user's face to calculate the photographing angle, and calculates the corrected viewing angle with the calculated photographing angle. Since the viewing angle of the liquid crystal screen display unit 140 is adjusted after the calculation, the user is first photographed before adjusting the viewing angle of the liquid crystal display unit 140.

The user checks the message output to the liquid crystal display 140, and photographs at the position and angle to be photographed by operating the key input unit 130 (S230). When shooting is selected by the user and a shooting signal is input from the key input unit 130, the microprocessor 110 controls the camera unit 150 to convert an image input from the mounted small lens into an optical signal and an image signal in order. To generate a captured image as image data.

When the image of the user is generated, a specific portion of the face of the user is recognized from the captured image (S240). That is, the microprocessor 110 compares the captured image according to the algorithm of the viewing angle adjusting software being executed with the stored image stored in the memory unit 120. The stored image is an image containing the shape of a specific part of the user's face. Therefore, the microprocessor 110 searches whether there is a part in the captured image that matches the stored image in units of blocks, and recognizes the block as a specific part when there is a matching block.

Here, the specific area may be specified variously, such as eyes, nose, mouth, ears, and eyebrows of the user's face. In order to recognize a specific area, it is preferable to select the eyebrow that is the most easily compared as a specific area, but in the present invention, since the viewing angle is adjusted so that a user can see the screen output on the liquid crystal display 140 without distortion, It is desirable to select eyes. Hereinafter, a preferred embodiment of the present invention will be described assuming that a specific part is selected by the eye.

The microprocessor 110 that recognizes the eye as a specific part calculates a photographing angle by calculating a distance between the eye and the camera, and calculates a corrected viewing angle using the photographing angle (S250).

That is, the microprocessor 110 calculates the average coordinate value as the average value of the coordinate values of the two eyes of the user by converting the position on the screen on which the captured image is output to the liquid crystal screen display unit 140 into coordinates, and at the center of the coordinates. The photographing angle and the corrected viewing angle are calculated as the difference value from to. A method of calculating the photographing angle and the corrected viewing angle will be described in detail with reference to FIG. 3.

The microprocessor 110 that calculates the corrected viewing angle adjusts the viewing angle of the liquid crystal display 140 to the corrected viewing angle (S260). That is, the microprocessor 110 transmits information on the corrected viewing angle to the liquid crystal display 140 and supplies the liquid crystal panel according to the information on the corrected viewing angle received by the liquid crystal display 140 using the supply power supply. By controlling the power supply, the LCD panel outputs the screen at the corrected viewing angle.

As a result, the liquid crystal display 140 of the mobile communication terminal outputs a screen at the corrected viewing angle until a request is made to switch to the original viewing angle through a separate key input unit 130 from the user. Therefore, the user can take a picture at a desired angle while viewing the screen output at the corrected viewing angle and the screen which is not distorted from the side.

3 is an exemplary view for explaining a method of calculating a photographing angle and a correction angle according to a preferred embodiment of the present invention.

As described with reference to FIG. 2, the microprocessor 110 recognizes the user's eyes in the captured image and obtains coordinate values for the positions of the eyes.

In 3A, an image of the user is output to the LCD screen 140 of the mobile communication terminal. In the captured image, the user's eyes are located in the upper right corner.

3B converts the liquid crystal display into coordinates and displays the position of the eye on the coordinates.

When the screen output from the LCD screen display unit 140 is converted into coordinates, it may be expressed as 3B. The screen output by the liquid crystal display 140 may be screen of various sizes according to the manufacturing technique.

In other words, assuming that the horizontal axis is the x-axis and the vertical axis is the y-axis, assuming that the uppermost coordinate value is the start value (0.0) and the lower right coordinate value is the end value (200, 200) (the unit of the coordinate is Pixels), and the screen output to the liquid crystal display 140 is 200 pixels × 200 pixels in size. Here, the coordinate value of the center is (100, 100).

The microprocessor 110 that recognizes eyes from the image captured on the screen output as shown in 3A converts the two eyes of the user into coordinate values on the coordinates, and averages the coordinate values of the two eyes on the x-axis and the y-axis. The median values of the two eyes are set as the coordinate values of the eyes by calculating the value. Here, it is assumed that the user's eye shown in 3A is located at the top right of the center of the screen, so the coordinates of the eye are (150, 50).

Once the coordinate values of the eye are determined, the coordinate value difference from the center of the eye to the coordinate values of the eye can be calculated. As described above, since the coordinate value of the eye is (150, 50)) and the coordinate value of the right center is (100, 100), the eye coordinate value is 50 pixels in the x-axis direction and 50 in the y-axis direction from the center. Are pixels apart.

On the other hand, the camera converts the image input to the small lens into an electrical signal to image the whole range of objects in the vertical, vertical, left and right directions, and the subject only at a certain angle vertically, vertically, or vertically from the small lens of the camera. You can shoot. Since the camera may also have a different shooting angle according to the manufacturing technique, it is assumed here that the camera unit 150 may shoot up to 45 ° in the vertical direction of the small lens.

3C shows the photographing angle on the LCD screen converted into coordinates.

According to the above assumptions about the photographing angle, if the photographing angle is displayed on the coordinate shown as 3B, the photographing angle according to the coordinate as shown in 3C can be obtained.

Since the camera can shoot up to 45 ° in up, down, left, and right, the tip of the top, bottom, left and right has a 45 ° shooting angle. Therefore, if the center of the coordinate value (100, 100) is set to 0 °, the image is taken up to 45 ° in the x-axis direction, up to 45 ° in the y-axis direction, and captured up to 90 ° in each of the up, down, left, and right directions. . Thus, the x-axis is taken from -45 ° to + 45 ° and the y-axis is taken from -45 ° to + 45 °.

That is, the shooting angle at the point with coordinate values (200, 100) becomes + 45 ° on the x axis and 0 ° on the y axis, and the shooting angle on the point with coordinate values (100, 0) is 0 ° on the x axis. , y-axis becomes + 45 °.

On the other hand, since the coordinate value of the eye is (150, 50), it is separated by 50 in the x-axis and 50 in the y-axis from the central coordinate value (100, 100). + 22.5 ° and + 22.5 ° on the y-axis. That is, the photographing angle can be calculated by proportionally converting the difference between the coordinate value of the specific region and the coordinate value of the center of the maximum photographing angle of each of the x-axis and the y-axis.

Through this, the photographing angle may be calculated using the image photographing the user, and the corrected viewing angle may be calculated using the calculated photographing angle.

The corrected viewing angle can be calculated from the photographing angle. Since the user's eyes are separated from the center by the photographing angle, the LCD screen can be corrected by the photographing angle and outputted. In other words, the corrected viewing angle is + 22.5 ° on the x axis and + 22.5 ° on the y axis.

In the above description, the correction viewing angle is calculated after photographing a user using a camera mounted in the mobile communication terminal, and the LCD screen is corrected to the corrected viewing angle, and the output is described. However, the technical matters of the present invention are not limited thereto. A computer device having a camera and a display device, such as a digital camera, a digital camcorder, a computer with an image camera, which can photograph a subject using a camera and directly output the same, may be applied.

The above description is merely illustrative of the technical idea of the present invention, and those skilled in the art to which the present invention pertains may make various modifications and changes without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

As described above, according to the present invention, it is possible to accurately calculate the viewing angle by using the camera to accurately determine the position of the user, and to adjust the viewing angle according to the user's gaze as well as to adjust the viewing angle according to the situation up, down, left, and right. It is possible to reduce the eye fatigue that can occur because the display device must be viewed from the top, bottom, left and right sides, and there is an effect of not revealing the screen output on the display field of the electronic device used by the surrounding people. .

Claims (11)

A memory unit for storing data, a camera unit for photographing a subject to generate an image, a key input unit for receiving keys, a liquid crystal screen display unit for outputting a screen, and the memory unit, the camera unit, the key input unit, and the liquid crystal screen display unit A method of controlling a viewing angle of a screen by recognizing a location of a user in a display device including a controlling microprocessor, (a) driving the camera unit to photograph the subject and generate a photographed image; (b) recognizing a specific part of the image by comparing the image with a stored image previously stored in the memory unit; (c) calculating a corrected viewing angle by calculating a photographing angle with the specific part; And (d) transferring the corrected viewing angle to the liquid crystal display to control the liquid crystal display to output the screen at the corrected viewing angle. Recognizing the location of the user characterized in that it comprises a method of controlling the viewing angle. The method of claim 1, And the corrected viewing angle is a predetermined angle of up, down, left, and right from a right angle direction of the center. The method of claim 1, wherein step (c) comprises: (c1) converting the screen into coordinates and generating a specific part coordinate value by converting a position of the specific part into a coordinate value on the coordinate; (c2) calculating a difference value by calculating a difference between a coordinate value at the center of the coordinate and the specific portion coordinate value in the x-axis and the y-axis, respectively; (c3) calculating a maximum recordable angle of the camera with respect to the right angle of the center; (c4) calculating the photographing angle by calculating an angle of the difference value with respect to the right center of the center as a ratio of the maximum photographable angle; And (c5) setting the corrected viewing angle to the photographing angle Recognizing the location of the user characterized in that it comprises a method of controlling the viewing angle. The method of claim 1, wherein step (d) By adjusting the driving voltage supplied to the liquid crystal panel (Panel) of the liquid crystal display according to the corrected viewing angle to adjust the transmission intensity of the liquid crystal panel to set the corrected viewing angle, the viewing angle by recognizing the user's position How to control. The method of claim 4, wherein step (d) A method of controlling a viewing angle by recognizing a user's position, wherein the liquid crystal panel is narrowed by the driving voltage by adjusting the driving voltage to narrow the viewing angle, and the liquid crystal panel is made wide viewing angle by decreasing the transmission intensity. . A display device for outputting a screen by controlling a viewing angle, A key input unit which receives a key from a user; A camera unit for photographing a user and generating a photographed image; A memory unit for storing a plurality of software for driving the display device and performing additional functions, a viewing angle adjusting software for adjusting the viewing angle, and a stored image which is an image of a user image photographed by the camera unit and a shape of a specific part; ; A liquid crystal display including a liquid crystal panel and a driving power supply, and outputting the screen by adjusting a viewing angle according to an input control signal; And By analyzing the key value input from the user and executing the viewing angle adjusting software, the camera unit is controlled by the camera according to a predetermined algorithm of the viewing angle adjusting software to photograph the user, and the photographed image and the stored image are compared to the specific portion. A microprocessor for calculating a photographing angle for the specific portion, calculating a corrected viewing angle, and then controlling the liquid crystal display to output the screen at the corrected viewing angle. A display device for controlling a viewing angle by recognizing a location of a user including a. The method of claim 6, And the corrected viewing angle is a predetermined angle of up, down, left, and right from a right angle direction of the center. The method of claim 6, wherein the microprocessor, Converts the screen into coordinates, generates a specific part coordinate value by converting the position of the specific part into a coordinate value on the coordinate, and calculates the difference between the coordinate value of the center of the coordinate and the specific part coordinate value in left and right directions After calculating the difference value by calculating each in the y-axis direction, which is the x-axis and the up-and-down direction, the maximum possible angle of shooting of the camera with respect to the right angle of the center is calculated, and the angle of the difference value with respect to the right angle of the center. Calculating the photographing angle by calculating a ratio as the ratio of the maximum photographable angle to controlling the viewing angle. The method of claim 6, wherein the microprocessor, And setting the corrected viewing angle as the photographing angle and transferring the corrected viewing angle to the liquid crystal display, thereby controlling the viewing angle. The liquid crystal display of claim 6, wherein Adjusting the driving voltage supplied to the liquid crystal panel according to the corrected viewing angle to adjust the transmission intensity of the liquid crystal panel to output the screen at the corrected viewing angle to recognize the position of the user to control the viewing angle Display device. The liquid crystal display of claim 6, wherein Display of controlling the viewing angle by recognizing the user's position, characterized in that the liquid crystal panel is narrower viewing angle by adjusting the driving voltage to strengthen the transmission intensity, and the liquid crystal panel is wider viewing angle by weakening the transmission intensity. Device.

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