A method for adjusting the display content of a liquid crystal screen according to an observation point

Abstract

The present invention relates to a method for adjusting the display content of a liquid crystal screen according to an observation point, including two parts: image angle correction and brightness correction. The image angle correction is to adjust the display angle of the image according to the obtained pose so that it can present an effect where both eyes are on a straight line perpendicular to the center point of the display content. The brightness correction calculates the proportional relationship with the human eye based on the relationship between the actual size of the screen and the number of pixels, and performs correction according to the correction coefficient. The present invention can enable the observer to be free from the influence of distortion and observe a normal effect. At the same time, it corrects the problem of uneven brightness felt due to different observation distances of different liquid crystal points from the human eye, so that it is not easy to have a sense of dizziness even during long-term observation.

Description

Technical Field

[0001] The present invention relates to the field of liquid crystal display screens, and more specifically, to a method and a liquid crystal display screen for adjusting the display content of the liquid crystal display screen according to the position of the long-term observation points of the human body, so as to obtain a planar effect and balanced brightness at the actual observation points thereof. Background Art

[0002] The liquid crystal display screen is a very important human-computer interaction device, which is almost ubiquitous in existing electronic products and is an indispensable item in modern society.

[0003] When observing a liquid crystal display screen, the ideal observation position is that both eyes are on the straight line perpendicular to the center point of the liquid crystal display screen. However, in some specific environments, the liquid crystal display screen is in a fixed position, and there is often only one user, and the observation angle of this user is always biased at a certain fixed angle and position, rather than the normal optimal observation position and distance at the center point. In this case, the observer always observes a distorted image, which affects the observation effect, and dizziness is likely to occur during long-term observation. In addition, due to the different distances between the positions of different liquid crystals of the liquid crystal display screen and the observer's eyes, the observed brightness will also change from bright to dark, resulting in imbalance.

[0004] If there is a method and a liquid crystal display screen that can adjust the original display of the liquid crystal display screen on the premise of inputting the attitude (position, angle) of the observation value relative to the liquid crystal display screen, so that it can present an optimal effect for the observer with both eyes on the straight line perpendicular to the center point of the liquid crystal display screen. Then it can enable the observer to be unaffected by distortion and observe a normal effect, and dizziness is not likely to occur during long-term observation. In addition, if the problem of unbalanced brightness caused by different observation distances of different liquid crystal points from the human eye can be corrected, the human eye's perception effect will also be improved.

[0005] The prior art cannot meet the above requirements. Summary of the Invention

[0006] The object of the present invention is to propose a set of methods and liquid crystal display screens for adjusting the display content of the liquid crystal display screen according to the pose of the long-term observation points of the human body on the basis of existing electronic technology and machine vision technology, so that it can present an optimal effect for the observer with both eyes on the straight line perpendicular to the center point of the liquid crystal display screen, that is, the observer can obtain a planar effect and balanced brightness at the actual observation points.

[0007] The method for adjusting the display content of the liquid crystal screen according to the observation point according to the present invention includes two parts: image angle correction and brightness correction. Among them, the image angle correction is to adjust the display angle of the image according to the obtained pose so that it can present an effect in which both eyes are on a straight line perpendicular to the center point of the display content. The brightness correction is that although the function of the image angle correction can correct the angle and other contents of the image, since the distances of different liquid crystals on the liquid crystal screen from the observer's eyes are from near to far, the observed brightness will also change from bright to dark, resulting in imbalance. Therefore, it is necessary to correct its brightness. The modification method is to calculate the proportional relationship with the human eye based on the relationship between the actual size of the screen and the number of pixels, and correct it according to the correction coefficient.

[0008] The specific steps of the method according to the present invention are as follows:

[0009] 1. Image angle correction

[0010] Step 1.1: Transform the angle of the user relative to the liquid crystal screen obtained from the pose perception device. Taking the center point of the liquid crystal screen as the origin, and taking the X-Y-Z coordinates of the liquid crystal screen as the original coordinate system 1, the horizontal direction of the liquid crystal screen coordinate system is the X-axis, and the rightward direction is the positive direction; the vertical direction of the liquid crystal screen coordinate system is the Y-axis, and the downward direction is the positive direction; the vertical direction of the liquid crystal screen coordinate system is the Z-axis, and the direction to the far away is the positive direction. The two eyes of the user are the offset coordinate system 2. The horizontal direction of the user coordinate system is the X-axis, and the rightward direction is the positive direction; the vertical direction of the user coordinate system is the Y-axis, and the downward direction is the positive direction; the vertical direction of the user coordinate system perpendicular to the film is the Z-axis, and the direction to the far away is the positive direction.

[0011] Let the deflection angles of the offset coordinate system 2 relative to the original coordinate system 1 expressed by the X-Y-Z fixed angle coordinate system (common knowledge in the field of robotics) be α, β, and γ, and the coordinates of the spatial positions of the user's two eyes relative to the original coordinate system 1 be (lx, ly, lz). Calculate the respective flipping equations of the three fixed angles as Rz(α), Ry(β), and Rx(γ):

[0012]

[0013]

[0014]

[0015] Calculate the combined flipping equation of the three fixed angles as R:

[0016]

[0017] The expression method of the X-Y-Z fixed angle coordinate system involved in this step is common expression content in machine vision, and the applicant will not elaborate here.

[0018] Step 1.2: Calculate the transformation matrix of the spatial distance as H:

[0019]

[0020] The transformation matrix for calculating the spatial distance is the inverse Hv of H. Matrix inversion is a common linear algebra problem and will not be elaborated here. The inv symbol represents inversion.

[0021] Hv = inv(H)

[0022] Step 1.3: Set the original image as P1. Then the preliminarily optimized image P2 is:

[0023] P2 = Hv · P1

[0024] 2. Brightness correction

[0025] 2.1. Assume that there are Mx liquid crystals on the x-axis and My liquid crystals on the y-axis of the liquid crystal screen. Consistent with Step 1.1, the spatial positions of the user's two eyes relative to the original coordinate system 1 are set as (lx, ly, lz).

[0026] Calculate the linear spatial distance between the human eye and the center point of the liquid crystal screen:

[0027]

[0028] Step 2.2: The correction formula for each liquid crystal point is:

[0029]

[0030] Where P2(i, j) is the result of Step 1-3. Here, i represents the i-th liquid crystal point on the x-axis, ranging from 1 to Mx, and j represents the j-th liquid crystal point on the y-axis, ranging from 1 to My.

[0031] The meaning of the sgn() symbol is to take the positive or negative sign of its parameter. For example, sgn(7) = 1, sgn(-0.1) = -1, sgn(0) = 0; pa is the correction coefficient.

[0032] Step 3.3: Take the P3(i, j) obtained in Step 2.2 as the output and display it on the liquid crystal screen.

[0033] The advantages of the present invention are as follows: First, it can enable the observer to be free from the influence of distortion and observe normal effects. Second, it can correct the problem of uneven brightness felt due to different observation distances of different liquid crystal points from the human eye. Third, it is not easy to cause dizziness even during long-term observation.

[0034] During the use of the present invention, two devices, namely a liquid crystal display screen and a pose perception device, are used in combination. Among them, the function of the liquid crystal display screen is to display information and achieve human-computer interaction. Its function also lies in that after obtaining the pose information of the pose perception device, the display information is corrected and displayed according to the method described in the present invention. The function of pose perception is to obtain the pose of the long-term observation points of the human body and transmit it to the CPU built in the liquid crystal display screen for correcting the display information. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 Schematic diagram of the structural relationship of the embodiment of the present invention;

[0036] Figure 2 Schematic diagram of the relationship of the three rotation angles of the embodiment of the present invention;

[0037] Figure 3 Schematic diagram of a relationship coordinate of the embodiment of the present invention;

[0038] Figure 4 Schematic diagram of the pose perception input device adopted in the embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0039] The following will further explain the present invention in conjunction with Figure 1 Figure 4 ...

[0040] As Figure 1 shown, the function of the liquid crystal display screen in the present invention is to display information and achieve human-computer interaction. Its function also lies in that after obtaining the pose information of the pose perception device, a correction algorithm is run to realize the correction of the display information and achieve the main advantages proposed by the present invention. In this embodiment, the liquid crystal display screen adopted is a 32-inch LCD liquid crystal display screen of Jiangsu Austin Optoelectronic Technology Co., Ltd., and the CPU is open, and there is still a certain amount of computing resources remaining.

[0041] Figure 1 , 1 represents the liquid crystal display screen, 2 represents the pose perception device, 3 and 5 represent the offset observer angles, and 4 represents the best position when the relatively reasonable eyes are on the straight line perpendicular to the center point of the liquid crystal display screen.

[0042] The function of the pose perception device involved in the present invention is to obtain the pose of the long-term observation points of the human body and transmit it to the CPU built in the liquid crystal display screen for further correction algorithms. It can either be a common human body perception device such as Microsoft's Kinect, with Kinect providing data; or it can be based on a rotary resistor, and the observer adjusts the input data by himself, such as Figure 4As shown in the figure, this is the simplest manual input version of the pose perception device adopted in this embodiment, that is, it is adjusted by personnel using a knob switch. It has 1 group of switches and 6 groups of EC11 type 20K rotary resistors. The STM32F401 single-chip microcomputer is used to read the resistance values of the 6 groups of rotary resistors as the rotation angle γ and offset lx in the X direction, rotation angle β and offset ly in the Y direction, rotation angle α and offset lx in the Z direction, and output them to the CPU of the liquid crystal display screen. The function of the 1 group of switches is to turn on and off the function of input parameters, that is, when adjustment is required, data is output to the liquid crystal display screen, and this function is turned off usually.

[0043] As Figure 2 , Figure 3 shown, the method for adjusting the display content of the liquid crystal display screen according to the observation point described in the present invention includes two major parts: image angle correction and brightness correction, which are described separately as follows:

[0044] The content of image angle correction is to adjust the display angle of the image according to the obtained pose so that it can present an effect where the two eyes are on a straight line perpendicular to the center point of the display content. The specific steps are as follows:

[0045] Step 1-1: Take the angle transformation of the user relative to the liquid crystal display screen obtained from the pose perception device. Take the center point of the liquid crystal display screen as the origin, and take the X-Y-Z coordinates of the liquid crystal display screen as the original coordinate system 1. The horizontal direction of the liquid crystal display screen coordinate system is the X axis, and the right direction is the positive direction; the vertical direction of the liquid crystal display screen coordinate system is the Y axis, and the downward direction is the positive direction; the vertical direction of the liquid crystal display screen coordinate system is the Z axis, and the direction to the distance is the positive direction. The two eyes of the user are the offset coordinate system 2. The horizontal direction of the user coordinate system is the X axis, and the right direction is the positive direction; the vertical direction of the user coordinate system is the Y axis, and the downward direction is the positive direction; the vertical direction of the user coordinate system perpendicular to the film is the Z axis, and the direction to the distance is the positive direction.

[0046] Let the deflection angles of the offset coordinate system 2 relative to the original coordinate system 1 expressed by the X-Y-Z fixed angle coordinate system (common knowledge in the field of robotics) be set as α, β, and γ, and the coordinates of the spatial positions of the two eyes of the user relative to the original coordinate system 1 be set as (lx, ly, lz). Calculate the respective flipping equations of the three fixed angles as Rz(α), Ry(β), and Rx(γ):

[0047]

[0048]

[0049]

[0050] Calculate the combined flipping equation of the three fixed angles as R:

[0051]

[0052] Step 1-2, calculate the transformation matrix for spatial distance as H:

[0053]

[0054] Calculate the inverse Hv of the transformation matrix H for spatial distance. Matrix inversion is a common linear algebra problem and will not be elaborated here. The inv symbol represents inversion.

[0055] Hv = inv(H)

[0056] For example: Assume that the observer's eyes are parallel at the left boundary of the center point of the liquid crystal screen. The X-axis of the liquid crystal screen is 1 meter and the Y-axis is 0.8 meter, and the distance from the human eyes to the liquid crystal screen is 0.5 meter. Then it can be known that at this time, when the human eyes observe the center point of the liquid crystal screen, it rotates 45 degrees around the Y-axis. That is, at this moment, the synthesized flipping equation R only relates to Y because the other XZ axes do not move:

[0057]

[0058] At this moment, since the human eyes are parallel at the left boundary of the liquid crystal screen and in millimeters, so lx = -500. Because they are parallel, so ly = 0. Because the human eyes are 0.5 meter away from the liquid crystal screen, so lz = 500;

[0059] Therefore

[0060]

[0061] Then find the inverse of H:

[0062]

[0063] Then the corrected image can be calculated according to P2 = Hv * P1, where P1 is the original digital image to be displayed.

[0064] Step 1-3, assume the original image is P1, then the initially optimized image P2 is:

[0065] P2 = Hv · P1

[0066] The content of brightness correction is that although the function of image angle correction can correct the angle and other contents of the image, due to the different distances from the positions of different liquid crystals on the liquid crystal screen to the observer's human eyes, which vary from near to far, the observed brightness will also change from bright to dark, resulting in imbalance. Therefore, it is necessary to correct its brightness.

[0067] The steps are as follows: Calculate the proportional relationship with the human eyes using the relationship between the actual size of the screen and the number of pixels, and perform correction according to the correction coefficient, specifically as follows:

[0068] Step 2-1: Assume that there are Mx liquid crystals on the x-axis and My liquid crystals on the y-axis of the liquid crystal screen. Consistent with Step 1.1, at this moment, the spatial positions of the user's two eyes relative to the original coordinate system 1 are set as (lx, ly, lz).

[0069] Calculate the linear spatial distance between the human eye and the center point of the liquid crystal screen:

[0070]

[0071] Step 2-2: The correction formula for each liquid crystal point is:

[0072]

[0073] Where P2(i,j) is the result of Step 1-3, where i represents the i-th liquid crystal point on the x-axis, ranging from 1 to Mx, and j represents the j-th liquid crystal point on the y-axis, ranging from 1 to My.

[0074] Among them, the meaning of the sgn() symbol is to take the positive or negative sign of the parameter therein. For example, sgn(7)=1, sgn(-0.1)=-1, sgn(0)=0; pa is the correction coefficient.

[0075] In the embodiment of the present invention, the pixel value of 1000*800 is adopted, so Mx = 1000 and My = 800. Both parameters pa and pb are set to 10. The meaning of this is that the pixel value closest to the human eye has a maximum brightness of 255 - 10 = 245, while the farthest pixel value retains the original maximum brightness value of 255.

[0076] Step 2-3: Take P3(i,j) obtained in Step 2-2 as the output and display it on the liquid crystal screen.

[0077] For example: Continuing with the above, at this moment lx = -500, ly = 0, lz = 500, and the liquid crystal screen has Mx = 1000, My = 800; at this moment

[0078]

[0079]

[0080] By implementing the present invention, on the premise of inputting the attitude (position, angle) of the observed value relative to the liquid crystal screen, the original display of the liquid crystal screen can be adjusted so that it can present an optimal effect for the observer with both eyes on the straight line perpendicular to the center point of the liquid crystal screen. It can enable the observer to be unaffected by distortion and observe normal effects, and it is not easy to experience dizziness after long-term observation. In addition, it can correct the problem of uneven brightness felt due to different observation distances of different liquid crystal points from the human eye, and also improve the perception effect of the human eye.

Claims

1. A method for adjusting the display content of a liquid crystal screen according to an observation point, characterized in that It includes the following steps: 1) Image angle correction Step 1.1: Transform the angle of the user relative to the liquid crystal screen obtained from the pose perception device. Taking the center point of the liquid crystal screen as the origin, and taking the X - Y - Z coordinates of the liquid crystal screen as the original coordinate system 1. The horizontal direction of the liquid crystal screen coordinate system is the X - axis, with the right direction as the positive direction; the vertical direction of the liquid crystal screen coordinate system is the Y - axis, with the downward direction as the positive direction; the vertical direction perpendicular to the liquid crystal screen coordinate system is the Z - axis, with the direction towards the distance as the positive direction. The user's two eyes form the offset coordinate system 2. The horizontal direction of the user coordinate system is the X - axis, with the right direction as the positive direction; the vertical direction of the user coordinate system is the Y - axis, with the downward direction as the positive direction; the vertical direction perpendicular to the user coordinate system is the Z - axis, with the direction towards the distance as the positive direction. Let the deflection angles of the offset coordinate system 2 expressed in the X - Y - Z fixed - angle coordinate system relative to the original coordinate system 1 be α, β, γ, and the coordinates of the spatial positions of the user's two eyes relative to the original coordinate system 1 be (lx, ly, lz). Calculate the respective rotation equations for the three fixed angles as Rz(α), Ry(β), Rx(γ): Calculate the combined rotation equation for the three fixed angles as R: Step 1.2: Calculate the transformation matrix for the spatial distance as H: Calculate the inverse Hv of the transformation matrix H for the spatial distance. The inv symbol represents taking the inverse: Hv = inv(H) Step 1.3: Let the original image be P1, then the preliminarily optimized image P2 is: P2 = Hv·P1 2) Brightness correction 2.1: Assume that there are Mx liquid crystals on the x - axis of the liquid crystal screen and My liquid crystals on the y - axis. Consistent with Step 1.1, at this time, the coordinates of the spatial positions of the user's two eyes relative to the original coordinate system 1 are set as (lx, ly, lz); Calculate the linear spatial distance between the human eye and the center point of the liquid crystal screen: Step 2.2: The correction formula for each liquid crystal point is: Where P2(i,j) is the result of Step 1 - 3, where i represents the i - th liquid crystal point on the x - axis, ranging from 1 to Mx, and j represents the j - th liquid crystal point on the y - axis, ranging from 1 to My; The meaning of the sgn() symbol is to take the positive or negative sign of its parameter. sgn(7)=1, sgn(-0.1)= - 1, sgn(0)=0; pa and pb are correction coefficients; Step 3.3: Take P3(i,j) obtained in Step 2.2 as the output and display it on the liquid crystal screen.

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