TWI762035B - Display device - Google Patents

Abstract

A display device including a backlight source, an optical path adjusting layer, a diffuser, and a light modulation panel is provided. The light modulation panel and the backlight source are disposed on opposing sides of the optical path adjusting layer and the diffuser. The optical path adjusting layer provides a variable transmittance to a backlight produced by the backlight source. The backlight diffuses along a first direction and collimates along a second direction after transmitting through the diffuser. The first direction and the second direction are perpendicular to a normal vector of a display plane defined by the display device, and the first direction and the second direction are perpendicular to each other. The backlight forms a display light after transmitting through the optical path adjusting layer, the diffuser, and the light modulation layer. The display device adjusts the intensity of the backlight based on a grayscale value.

Description

display device

The present invention relates to a display device, in particular, to a liquid crystal display with high uniform gamma value at different viewing angles.

In a highly information-based modern age, as a window for human beings to watch the digital world, display devices have extensive, direct and profound impact on people's quality of life. Liquid crystal displays are one of the main types of conventional display devices. Compared with conventional cathode ray tube displays, liquid crystal displays have the advantages of being lighter, thinner, lower power consumption, and clearer.

However, the liquid crystal itself does not emit light, but relies on the illumination of the backlight to generate images, which leads to many problems. For example, the dark state pixels displayed by the liquid crystal panel are generated by the liquid crystal molecules blocking the backlight, but the asymmetrical arrangement of the liquid crystal molecules makes the liquid crystal light blocking direction limited. In other viewing angles, light leakage will be seen, but the dark state that the LCD panel is intended to present will not be seen. This light leakage phenomenon further causes a halo effect, so that the viewer can not see the object displayed in the image. Normal halo.

In addition to the aforementioned problem of light leakage in the dark state, there is also a problem due to the asymmetry when the liquid crystal displays the bright state at the frontal viewing angle. For example, when the liquid crystal molecules are arranged in a bright state for the front viewing angle, they show a light-shielding arrangement for some viewing angles. Therefore, if the viewer moves from the front viewing angle to a large viewing angle, the brightness of the image seen may decrease. The trend of color shift, such as color washout, which adversely affects the development quality, is seen.

In order to improve the dark-state light leakage and color dilution of the liquid crystal display, a conventional method is to collimate the backlight of the liquid crystal display, and use a lens film to diffuse the display light emitted from the liquid crystal panel. After the backlight is collimated, light leakage at large viewing angles is reduced; and the diffusion of display light can improve the phenomenon of color washout.

However, the aforesaid conventional technology improves the color dilution, but also causes the gamma value of the large viewing angle to be very different from the gamma value of the positive viewing angle, which leads to a sharp drop in contrast and makes the image seen at a large viewing angle unclear. . FIG. 2A shows the luminance distribution (horizontal angle luminance distribution) of the display light in the conventional technology at different horizontal viewing angles. As shown in FIG. 2A , the angular brightness distribution of the display light with different gray-level brightness in this conventional technique lacks uniformity. For example, the full width at half maximum of the display light with lower gray-level brightness is half the half-width of the display light with the highest gray-level brightness (255). The height and width are much larger. Therefore, the gamma value of the large viewing angle will be far from the gamma value of the positive viewing angle. In addition, there is still much room for improvement in the improvement of the halo effect in the conventional technology.

One of the main objectives of the present invention is to provide a display device that can have a gamma value similar to that of the frontal viewing angle at a large viewing angle.

In order to achieve the aforementioned purpose, in an embodiment of the present invention, a display device may include a backlight source, an optical path adjustment layer, a light diffusing film, and a light modulation panel. The light modulating panel can be arranged on the side of the light path adjusting layer and the light diffusing film opposite to the backlight source. The light path adjustment layer can provide variable transmittance to the backlight generated by the backlight source. The backlight can be diffused along the first direction and collimated along the second direction after passing through the light diffusing film. The first direction and the second direction are orthogonal to the plane normal vector of the display plane defined by the display device and the first direction and the second direction are orthogonal to each other. The backlight forms the display light after passing through the light path adjustment layer, the light diffusing film and the light modulation panel. The display device can adjust the brightness of the display light according to the gray scale value.

Under the action of the optical path adjustment layer, the angular luminance distributions along the first direction of the highest gray-scale luminance and the lower gray-scale luminance displayed by the display device tend to be consistent. Therefore, the front viewing angle of the display device of this embodiment and the larger viewing angle in the first direction have similar gamma values, so that the images viewed at the larger viewing angle can also show good contrast. In addition, the diffuser film diffuses the backlight along the first direction and aligns it along the second direction orthogonal to the first direction. Compared with the two-dimensional diffuser film, the contrast of the image can be improved. while still remaining bright.

1000: Display device

1010: Backlight

1020: Optical Path Adjustment Layer

1030: Diffuser film

1040: LCD panel

D1: first direction

D2: Second direction

L1: Backlight

L2: Display light

L_LC, L_255, L_P255, L_P64: Curve

θm: intersection angle

D3: Boundary direction

N: Display plane normal vector

A-A', B-B': hatching

C: Curve

θPeff: Equivalent edge angle

p1, p2: width

h1, h2: height

1050: The first celestial slice

1060: The second film

Φ0, Φ45: Axial

1070: Reflective polarizing film

θ1: first fillet

θ2: Second fillet

H1: first haze coating

H2: Second haze coating

P21: The Second Pillar

P22: The First Pillar

1080: The first bonding layer

1090: Second bonding layer

P11: Fourth Pillar

P12: The Third Pillar

FIG. 1A is a schematic diagram of a display device according to some embodiments of the present invention; FIG. 1B is a schematic diagram of a usage scenario of the display device according to some embodiments of the present invention; Schematic diagram; FIG. 2B is a diagram showing the angular brightness distribution of the present invention under different grayscale values; FIG. 3A is a diagram showing the angle of display light when the optical path adjustment layer provides the transmittance of the widest angular distribution in some embodiments of the present invention Schematic diagram of luminance distribution; FIG. 3B shows a schematic diagram of angular luminance distribution after the backlight passes through the optical path adjustment layer when the optical path adjustment layer provides a narrower angular distribution of transmittance in some embodiments of the present invention; FIG. 4 illustrates some embodiments of the present invention Figure 5A shows a schematic diagram of a light-diffusing film according to some embodiments of the present invention; Figure 5B shows a schematic cross-sectional view along the section line AA' of Figure 5A according to some embodiments of the present invention; 5C shows a schematic cross-sectional view along the section line BB' of FIG. 5A according to an embodiment of the present invention; FIG. 5D shows a schematic cross-sectional view along the section line BB' of FIG. 5A according to other embodiments of the present invention; FIG. 6 is a schematic diagram of a light-diffusing film, a crystal film and a backlight source according to some embodiments of the present invention; FIG. 7A is a schematic diagram of a backlight light field passing through the crystal film in some embodiments of the present invention; FIG. 7B shows an exemplary diagram of the axial direction of the present invention; FIG. 8A shows a schematic diagram of a light-diffusing film, a diaphanous film and a reflective polarizing film according to some embodiments of the present invention; FIG. 8B shows some other embodiments of the present invention. Schematic diagrams of a light-diffusing film, a polarizing film, and a reflective polarizing film; FIG. 9A shows a schematic diagram of a polarizing column according to some embodiments of the present invention; FIG. 9B shows a schematic diagram of a polarizing column according to some embodiments of the present invention; FIG. 10A depicts Figure 10B shows a schematic diagram of a silicon wafer and a light-diffusing film according to some embodiments of the present invention.

In this document, elements prefixed with ordinal numbers (eg, "first," "second," "third," etc.) do not necessarily imply that the elements have a particular order. Rather, these ordinal numbers are only used to refer to different elements of the same or similar type.

It should be noted that the content of the drawings in this document is only illustrative, so the dimensions, proportions and numbers shown in the drawings do not necessarily match the dimensions, proportions and numbers of actual implementations.

Referring to FIG. 1A , in some embodiments of the present invention, a display device 1000 includes a backlight source 1010 , an optical path adjustment layer 1020 , a light diffusing film 1030 and a liquid crystal panel 1040 . However, the present invention is not limited to this. For example, in other embodiments, the liquid crystal panel 1040 can be replaced by other types of light modulation panels. As shown in FIG. 1A , in some embodiments, the light diffusing film 1030 may be disposed between the liquid crystal panel 1040 and the optical path adjustment layer 1020 , but the present invention is not limited to this. In different embodiments, the optical path adjustment layer 1020 and The light diffusing film 1030 can be disposed between the backlight source 1010 and the liquid crystal panel 1040 in different arrangements. For example, in other embodiments, the light diffusing film 1030 may also be disposed between the backlight source 1010 and the light path adjustment layer 1020 . With the diffuser film 1030 provided in the optical path adjustment Compared with the embodiment of the layer 1020 and the backlight source 1010, the embodiment in which the light diffusing film 1030 is disposed between the liquid crystal panel 1040 and the optical path adjustment layer 1020 can make the gamma value more ideal (for example, the average value of the gamma value of each viewing angle is higher. close to 2.2). Furthermore, it should be noted that, herein, the statement "the first element is provided between the second element and the third element" does not exclude that there is a provision between the first element and the second element or between the first element and the third element Possibility of other components. In some embodiments, the optical path adjustment layer 1020 may not include a polarizer, but the invention is not limited thereto. Compared with the embodiment in which the optical path adjustment layer 1020 includes the polarizer, the embodiment in which the optical path adjustment layer 1020 does not include the polarizer can have higher light transmittance, thereby enhancing the display brightness of the display device.

As shown in FIG. 1A , in this embodiment, the backlight source 1010 generates a backlight L1 , and the backlight L1 propagates from the backlight source 1010 to the liquid crystal panel 1040 , and the normal vector N of the display surface is substantially related to the backlight source 1010 , the optical path adjustment layer 1020 , the light diffusing The alignment directions of the film 1030 and the liquid crystal panel 1040 are parallel. Specifically, the display surface normal vector N is the normal vector of the display surface defined by the display device 1000 . For example, when the display device 1000 is a flat display, the display plane can be defined as a plane that is substantially the same as the surface on which the display device 1000 displays images; when the display device 1000 is a curved display, the display plane can be defined as the surface on which the display device 1000 displays images The surface is a plane formed by projecting the backlight source 1010 , the optical path adjustment layer 1020 , the light diffusing film 1030 and the liquid crystal panel 1040 along the arrangement direction.

In this embodiment, preferably, as shown in FIG. 1B , the first direction D1 may be the horizontal direction in which the viewer looks at the display device 1000 , and the second direction D2 may be the direction in which the viewer looks at the display device 1000 . The vertical direction, and the normal vector N of the display surface can be the depth direction of the viewer looking at the display device 1000, but the present invention is not limited to this.

In this embodiment, the display device 1000 causes the backlight L1 passing through the light path adjustment layer 1020 and the light diffusing film 1030 to form the display light L2 according to the gray scale value. For example, the display device 1000 can adjust the grayscale brightness of the display light L2 through a voltage modulation method or a spatial modulation method. For example, the grayscale value of The highest value and the lowest value can be 255 and 0, respectively, and the display device 1000 can make the display light L2 have the highest brightness and the lowest brightness respectively when the gray scale value is the highest value and the lowest value.

In this embodiment, on the plane determined by the first direction D1 and the normal vector N of the display surface, the light path adjustment layer 1020 can make the display light L2 with the highest gray level value and the lower gray level value along the first direction D1 The angular luminance distributions are similar to each other. In this document, the term "light field" and the term "angular luminance distribution" are used interchangeably. Since the display light L2 emitted by the display device 1000 of the present invention has a similar angular luminance distribution along the first direction D1 at the highest grayscale value and the lower grayscale value, the display light L2 can also exhibit a large viewing angle in the first direction A comparison similar to the frontal viewing angle is detailed below.

Referring to FIG. 1 and FIG. 2B together, FIG. 2B shows the display light L2 formed by the optical path adjustment layer 1020 of the present invention at different grayscale values along the plane determined by the first direction D1 and the normal vector N of the display surface. A graph of the angular luminance distribution along the first direction D1. In the present invention, the light field distribution of the display light L2 with the highest grayscale value and the lower grayscale value along the first direction D1 has a higher similarity through the light path adjustment layer 1020 . In detail, FIG. 2B shows the display light L2 of the highest gray level and the display light L2 of the highest gray level (eg, 96) of 34% to 38%. The difference between the full width at half maximum and the full width along the first direction D1 is less than 30 degrees; FIG. 2B also shows The difference between the full width at half maximum of the display light L2 showing the highest gray level value and the display light L2 of 23% to 27% of the highest gray level value (eg, 64) along the first direction D1 is also less than 30 degrees. In comparison, as shown in FIG. 2A , the angular luminance distribution of the display light emitted by the conventional liquid crystal display as the control group is relatively inconsistent along the first direction D1 under different grayscale values.

Specifically, the gamma value is a power-law relationship between the brightness of the display light L2 and the grayscale value. Under the same grayscale value, the brightness of the display light L2 will increase according to the power law as the gamma value increases. . The present invention uses the optical path adjustment layer 1020 to make the display light L2 of the lower gray level and the display light L2 of the highest gray level exhibit similar angular brightness distribution, so the present invention can provide a larger viewing angle and a front viewing angle similar to that of the prior art. gamma value. Therefore, it is conceivable that the display device of the present invention displays The contrast of the images in the larger viewing angle is also similar to the contrast of the front viewing angle, so when the viewer moves from the front viewing angle to the larger viewing angle, the images they see will maintain a similar contrast to achieve a better viewing experience.

Referring to FIG. 1 again, the light path adjustment layer 1020 can provide variable transmittance to the backlight L1 according to the gray scale value. Herein, the transmittance provided by the light path adjustment layer 1020 to the backlight L1 refers to the effective transmittance of the backlight L1 passing through the light path adjustment layer in different viewing angles. Specifically, the transmittance provided by the light path adjustment layer 1020 varies with Depending on the viewing angle, that is, the transmittance provided by the optical path adjustment layer may have a non-uniform angular distribution. For example, the curve L_P64 shown in FIG. 3B can represent the transmittance of the light path adjustment layer 1020 providing the narrowest angular distribution in some embodiments, the backlight L1 passes through the light path adjustment layer 1020 along the first direction and the normal vector of the display surface The luminance distribution on the plane determined by N; the curve L_P255 shown in FIG. 3B can represent that when the light path adjustment layer 1020 provides the transmittance of the widest angle distribution in some embodiments, the backlight L1 passes through the light path adjustment layer 1020 along the The luminance distribution on the plane determined by the first direction and the normal vector N of the display surface. In some embodiments, the optical path adjustment layer 1020 can be implemented by, for example, a liquid crystal panel; in a preferred embodiment, the optical path adjustment layer 1020 can be a liquid crystal panel with a privacy protection function. Penetration rates for different angular distributions. The variable transmittance provided by the optical path adjustment layer 1020 will be described in detail below with reference to FIG. 1 , FIG. 3A and FIG. 3B .

In some embodiments, when the gray scale value is the highest value, the light path adjustment layer 1020 can provide the backlight L1 with the widest angular distribution of transmittance. In FIG. 3A , the curve L_LC represents that when the gray scale value is the highest value, the display light L2 formed by the backlight L1 only passing through the liquid crystal panel 1040 is along the first direction D1 and the plane determined by the normal vector N of the display surface along the first The angular brightness distribution in the direction D1; the curve L_255 represents the display light L2 in the first direction D1 and the display surface normal vector formed by the backlight L1 only passing through the optical path adjustment layer 1020 and the liquid crystal panel 1040 when the gray scale value is the highest value (eg 255). The angular luminance distribution along the first direction on the plane determined by N. As shown in FIG. 3A, 45 degrees in the first direction D1 In the viewing angle range to 55 degrees, the luminance of the curve L_255 is substantially about 80% to 100% of the luminance of the curve L_LC. In other words, in the viewing angle range of 45 degrees to 55 degrees between the first direction D1 and the display surface normal vector N on the plane determined by the first direction D1 and the display surface normal vector N, the light path adjustment layer 1020 provides the backlight L1 with The penetration rate of the widest angular distribution is roughly between 80% and 100%. Therefore, when the optical path adjustment layer of the present invention provides the transmittance with the widest angle distribution, it hardly blocks the backlight of the display device, and keeps the full width at half maximum of the backlight source.

In FIG. 3B , the curve L_P255 represents that when the grayscale value is the highest value (for example, 255), the backlight L1 only passes through the optical path adjustment layer 1020 along the first direction D1 and the normal vector N of the display surface along the plane determined by the first direction D1. The angular brightness distribution of the direction; the curve L_P64 represents that when the gray scale value is 25% of the highest value (for example, 64), the backlight L1 only passes through the optical path adjustment layer 1020 on the plane determined by the first direction D1 and the normal vector N of the display surface Angular luminance distribution along the first direction. As shown in FIG. 3B , in the viewing angle range of 45 degrees to 55 degrees in the first direction D1 , the luminance of the curve L_P64 is substantially less than 50% of the luminance of the L_P255 . In other words, in this embodiment, when the gray scale value is 25% of the highest value, in the viewing angle range of 45 degrees to 55 degrees in the first direction D1, the transmittance value provided by the light path adjustment layer 1020 to the backlight L1 is lower than 50% of the penetration value of the widest angular distribution. Thereby, the light path adjustment layer 1020 can shape the light field of the display light L2 of the lower gray level to be similar to the light field of the display light L2 of the highest gray level as described above.

Referring to FIG. 4 , the optical path adjustment layer 1020 has a boundary direction D3 that is orthogonal to the normal vector N of the display plane. As shown in FIG. 4 , in some embodiments, the optical path adjustment layer 1020 is arranged such that the boundary direction D3 and the first direction D1 is placed at an angle θm to avoid Moiré pattern. Preferably, the angle θm may be less than or equal to 20 degrees.

In some preferred embodiments, the light diffusing film 1030 diffuses the backlight L1 along the first direction D1 and aligns it along the second direction D2. For example, the light diffusing film 1030 can make the backlight L1 along the The full width at half maximum (FWHM) of the angular luminance distribution in the first direction D1 increases, and the full width at half maximum (FWHM) of the angular luminance distribution along the second direction D2 decreases.

In some embodiments, the backlight L1 is diffused along the first direction D1 and collimated along the second direction D2, so that the display light L2 emitted by the display device provided with the optical path adjustment layer 1020 of the present invention remains high For brightness, the light diffusing film 1030 preferably has the microstructure shown in FIG. 5A to FIG. 5D .

Referring to FIG. 5A , in some embodiments, the light diffusing film 1030 can be arranged along the first direction D1 and the second direction D2, the section line AA' is the section line parallel to the first direction D1, and the section line BB' is a section line parallel to the second direction D2.

5B shows a cross-section of the light diffusing film 1030 along the section line AA' of FIG. 5A. As shown in FIG. 5B , in some embodiments, the light diffusing film 1030 has a plurality of lens columns extending along the second direction D2 , and the cross section of the light diffusing film 1030 along the section line AA′ of FIG. 5A ( That is, on the cross section perpendicular to the second direction D2), the surface of the lens column of the light diffusing film 1030 presents a plurality of arcs with width p1 and height h1 side by side, preferably, the height h1 and width p1 The ratio is between 4% and 30%. It should be noted that the illustration in FIG. 5B does not limit the light-diffusing film 1030 of the present invention. In detail, in different embodiments, the cross-sections of the lens columns of the light-diffusing film 1030 along the first direction D1 may present different numbers and different Arc with a width and/or height and an aspect ratio between 4% and 30%. Preferably, on a cross-section perpendicular to the second direction D2, the equivalent angle θ Peff of the arc of the lens column of the light diffusing film 1030 along the first direction D1 is between 114 degrees and 158 degrees. , but the present invention is not limited to this.

Figures 5C and 5D show cross-sections of the light diffusing film 1030 along the section line BB' of Figure 5A (i.e., the cross-sections orthogonal to the first direction) in different embodiments. As shown in FIG. 5C , in some embodiments, the surface of the light diffusing film 1030 presents a straight line on a cross section perpendicular to the first direction. In other embodiments, as shown in FIG. 5D , the surface of the light diffusing film 1030 is perpendicular to the first direction. A curve C with a width p2 and a height h2 is presented on the cross section, and the height h2 corresponds to the length of the projection of the curve C on the normal vector N of the display surface. In these embodiments, the ratio of the height h2 to the width p2 is lower than 0.1%. It should be noted that the illustration in FIG. 5D does not limit the present invention, and in other embodiments, the light diffusing film 1030 may exhibit curves of different shapes on a cross section orthogonal to the first direction.

In some embodiments, the light field of the backlight of the display device can be further adjusted to make the light field of the display light more uniform, thereby further improving the problems of light leakage and color dilution. Referring to FIG. 6 and FIG. 7A together, in some embodiments, The first iris sheet 1050 and the second iris sheet 1060 can be disposed on the backlight source, so that the backlight L1 presents a light field that is wider along the first direction D1 and narrower along the second direction D2 as shown in FIG. 7A . In more detail, referring to FIG. 7A and FIG. 7B together, as shown in FIG. 7B , in this paper, the axial direction Φ0 is parallel to the normal vector N of the display surface, and the axial direction Φ45 and the axial direction Φ0 are sandwiched along the second direction D2 The included angle of 45 degrees; the light field shown in FIG. 7A is wider along the first direction (for example, has a larger full width at half maximum) on the plane determined by the axial direction Φ0 and the first direction D1, and the optical field in the axial direction Φ45 and the first direction D1 are wider along the first direction. The plane determined by the first direction D1 is narrower along the first direction (eg, has a narrower full width at half maximum).

In order to obtain the aforementioned backlight light field that is wider along the first direction in the axial direction Φ0 and narrower along the first direction on the plane determined by the axial direction Φ45 and the first direction D1, see FIG. 6 , in some embodiments , the arrangement direction of the first wafer 1050 is parallel to the first direction D1 to diffuse the backlight L1 along the first direction D1, and the arrangement direction of the second wafer 1060 is parallel to the second direction D2 to spread the backlight L1 along the first direction D1 Diffusion in the second direction D2. Preferably, the first lens 1050 can be disposed between the light diffusing film 1030 and the second lens 1060 , and the second lens 1060 can be placed between the first lens 1050 and the backlight 1010 .

Referring to FIGS. 8A and 8B together, in some embodiments, the display device 1000 may further include a reflective polarizing film 1070 . As shown in FIG. 8A , in some embodiments, the reflective polarizing film 1070 may be disposed between the light diffusing film 1030 and the first iris sheet 1050 . As shown in Figure 8B, in other In an embodiment, the reflective polarizing film 1070 may be disposed between the first iris sheet 1050 and the second iris sheet 1060 . In comparison, disposing the reflective polarizing film 1070 between the light diffusing film 1030 and the first polarizer 1050 can further increase the full width at half maximum of the display light L2 along the first direction, so that the display device 1000 can provide a wider The viewing angle of the reflective polarizing film 1070 is arranged between the first iris sheet 1050 and the second iris sheet 1060 to make the backlight L1 more collimated, thereby better improving the halo effect.

Referring to FIGS. 9A and 9B together, FIGS. 9A and 9B respectively show the cross-sectional structure of the pillars of the first wafer 1050 and the cross-sectional structure of the pillars of the second wafer 1060 in some embodiments. The top end of the prism of the first prism sheet 1050 has a first rounded angle θ1, and a surface opposite to the prism has a first haze coating H1. The top of the prism of the second prism sheet 1060 has a second rounded angle θ2, and a surface opposite to the prism has a second haze coating H2.

In some embodiments, the haze of the first haze coating H1 and the second haze coating H2 is less than 20%. Specifically, compared with the examples with haze higher than 20%, the examples with haze lower than 20% have higher front viewing angle brightness and front viewing angle contrast, and are determined in the axial direction Φ45 and the first direction D1 The highest brightness in all viewing angles along the first direction D1 on the plane is lower, and the halo effect can be improved remarkably.

In some embodiments, the equivalent radius r1 of the first rounded corner θ1 is greater than or equal to the equivalent radius r2 of the second rounded corner θ2. Specifically, compared with the embodiment in which the equivalent radius r1 is smaller than the equivalent radius r2, the embodiment in which the equivalent radius r1 is greater than or equal to the equivalent radius r2 can enable the backlight to pass through the second iris 1060 and the first iris. After 1050, it has a larger full width at half maximum along the first direction D1 within a range of about 0 degrees between the second direction D2 and the normal vector N of the display surface, and has a larger full width at half maximum along the second direction D2 and the display surface along the second direction D2. A viewing angle of 60 degrees along the first direction D1 within a range of about 0 degrees between the normal vector N and the phase of the normal vector N has higher brightness, which can make the display light field of the display device more uniform.

In some embodiments, the refractive index of the material of the first iris sheet 1050 (hereinafter referred to as the first refractive index) is less than or equal to the refractive index of the material of the second iris sheet 1060 (hereinafter referred to as the second refractive index). specific For example, compared with the embodiment with the first index of refraction greater than the second index of refraction, the embodiment with the first index of refraction less than or equal to the second index of refraction has a larger front viewing angle brightness and a greater contrast improvement; and the axial direction Φ45 and The highest brightness in all viewing angles along the first direction D1 on the plane determined by the first direction D1 is lower, and the halo effect can be significantly improved; and on the plane determined by the axial direction Φ0 and the first direction D1 It has a larger full width at half maximum in the first direction D1, and has a higher brightness along the 60-degree viewing angle of the first direction D1 on the plane determined by the axial direction Φ0 and the first direction D1, which can make the display light field more visible. evenly.

In some embodiments, the first fillet θ1 is greater than or equal to the second fillet θ2. Specifically, compared with the embodiment in which the first rounded corner θ1 is smaller than the second rounded corner θ2, the embodiment in which the first rounded corner θ1 is greater than or equal to the second rounded corner θ2 is located between the first direction D1 and the normal vector N of the display surface. The large viewing angle along the first direction D1 on the determined plane is less likely to leak light, and the halo effect can be significantly improved.

Referring to FIG. 10A , in some embodiments, a first bonding layer 1080 is disposed between the first iris sheet 1050 and the second iris sheet 1060 . In these embodiments, the second prism sheet 1060 includes a plurality of first prism posts P22 and a plurality of second prism columns P21. As shown in FIG. 10A , the height of the first pole P22 is greater than the height of the second pole P21, and the first pole piece 1050 and the second pole piece 1060 are connected to the first bonding layer through the first pole pole P22 1080 touch and fit. More preferably, in these embodiments, the total width of the first pillar P22 (that is, the sum of the lengths of the projections in the first direction D1 ) accounts for the first pillar P22 and the second edge. The total width of the mirror column P21 is 25% to 60%, so as to reduce the large viewing angle light leakage of the display light of the lowest luminance level along the first direction D1 on the axial direction Φ45 while achieving the required bonding strength.

Referring to FIG. 10B , in some embodiments, a second bonding layer 1090 is disposed between the first wafer 1050 and the light diffusing film 1030 . In these embodiments, the first panel 1050 includes a plurality of third pillars P12 and a plurality of fourth pillars P11. As shown in FIG. 10B , the height of the third pillar P12 is greater than the height of the fourth pillar P11 , and the first pillar 1050 and the light diffusing film 1030 pass through the third edge The mirror column P12 is in contact with the second bonding layer 1090 and is bonded. More preferably, in these embodiments, the total width of the third pillar P12 (that is, the sum of the lengths of the projections in the second direction D2) accounts for the third pillar P12 and the fourth pillar P12. The total width of the pillar P11 is 25% to 60%, so as to achieve the required bonding strength while reducing the lowest brightness level display light along the first direction D1 on the plane determined by the axial direction Φ45 and the first direction D1 of light leakage.

Although the present invention has been disclosed above through the embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection of the present invention The scope shall be determined by the scope of the appended patent application.

1000: Display device

1010: Backlight

1020: Optical Path Adjustment Layer

1030: Diffuser film

1040: LCD panel

D1: first direction

D2: Second direction

L1: Backlight

L2: Display light

N: Display surface normal vector

Claims (20)

A display device for generating a display light according to a grayscale value, the display device comprising: a backlight source, which generates a backlight; an optical path adjustment layer, which is used for providing a variable transmittance of the backlight, wherein the grayscale When the value is a maximum value, the variable transmittance of the backlight provided by the light path adjustment layer has a first angular transmittance distribution; when the grayscale value is a lower value than the maximum value, the light path adjustment The layer provides the variable transmittance of the backlight with a second angular transmittance distribution; a plane determined by a first direction and a plane normal vector along the first direction and the plane normal vector are sandwiched a first viewing angle range from 45 degrees to 55 degrees, within the first viewing angle range, the average value of the second angle transmittance distribution is lower than the average value of the first angle transmittance distribution; a light-diffusing film, After passing through the light diffusing film, the backlight diffuses along the first direction and is aligned along a second direction, the first direction is orthogonal to the second direction, wherein the display device defines a display plane, and the first direction is perpendicular to the second direction. One direction and the second direction are orthogonal to the plane normal vector of the display plane; and a light modulation panel is disposed on a side of the light path adjustment layer and the light diffusing film opposite to the backlight, wherein the The backlight forms the display light after passing through the light path adjustment layer, the light diffusing film and the light modulation panel. The display device of claim 1, wherein: in the first viewing angle range, the average value of the first angle transmittance distribution is between 80% and 100%. The display device according to claim 2, wherein: when the gray scale value is 23% to 25% of the highest value, the variable transmittance provided by the light path adjustment layer to the backlight has a second angle transmittance distributed; In the first viewing angle range, the average value of the second angle transmittance distribution is lower than 50% of the average value of the first angle transmittance distribution. A display device for generating a display light according to a gray scale value, the display device comprising: a backlight source for generating a backlight; an optical path adjustment layer for providing a variable transmittance of the backlight; wherein, the gray When the level value is a highest value, on a plane determined by a first direction and a plane normal vector, the angular luminance distribution of the display light has a first full width at half maximum along the first direction; the gray level value is At 34% to 38% of the highest value, on the plane determined by the first direction and the plane normal vector, the angular luminance distribution of the display light has a second full width at half maximum along the first direction; and the The light path adjustment layer makes the difference between the first full width at half maximum and the second full width at half maximum less than 30 degrees; and a light diffusing film, the backlight diffuses along the first direction and along a second direction after passing through the light diffusing film collimation, the first direction is orthogonal to the second direction, wherein the display device defines a display plane, the first direction and the second direction are orthogonal to a plane normal vector of the display plane; and a light adjustment The variable panel is disposed on a side of the optical path adjustment layer and the light-diffusing film opposite to the backlight source, wherein the backlight passes through the optical path adjustment layer, the light-diffusing film and the light-modulating panel to form the display light. The display device of claim 4, wherein: when the grayscale value is 23% to 27% of the highest value, on the plane determined by the first direction and the plane normal vector, the display light has a direction along the A third full width at half maximum in the first direction; and the optical path adjustment layer makes the difference between the first full width at half height and the third full width at half height less than 30 degrees. The display device according to claim 1 or 4, wherein a substantial symmetry axis of the optical path adjustment layer is orthogonal to the plane normal vector and is less than or equal to 20 degrees between the first direction. The display device according to claim 1 or 4, wherein the light-diffusing film has a plurality of lens columns extending along the second direction, and on a cross-section of the light-diffusing film perpendicular to the second direction, each of the The surface of the lens column exhibits an arc shape with an aspect ratio between 4% and 30%. The display device according to claim 7, wherein on a cross section of the light-diffusing film perpendicular to the first direction, a surface of the light-diffusing film presents a straight line. The display device according to claim 7, wherein, on a cross section of the light-diffusing film orthogonal to the first direction, a surface of the light-diffusing film presents a curve, and the projection of the curve on the plane normal vector The ratio of the length of the curve to the width of the curve is less than 0.1%. The display device as claimed in claim 1 or 4, further comprising a first film, the first film is disposed between the backlight and the light-diffusing film, and the pillars of the first film are along the The second direction extends. The display device of claim 10, further comprising a second panel, the second panel is disposed between the first panel and the backlight, and the pillars of the second panel are along the first panel. Extend in one direction. The display device as claimed in claim 11, further comprising a reflective polarized brightness enhancement film, the reflective polarized brightness enhancement film is disposed between the liquid crystal panel and the second wafer. The display device as claimed in claim 11, wherein: a first haze coating is provided on a side of the first wafer facing away from the pillar; the second wafer facing away from one of the pillars A second haze coating is arranged on the side; and the haze of the first haze coating and the second haze coating is lower than 20%. The display device of claim 11, wherein the refractive index of the prism material of the first prism sheet is less than or equal to the refractive index of the prism material of the second prism. The display device as claimed in claim 11, wherein the top of each pillar of the first iris sheet has a first rounded corner, and the top of each pillar of the second iris sheet has a second rounded corner, The equivalent radius of the first fillet is greater than or equal to the equivalent radius of the second fillet. The display device as claimed in claim 11, wherein the top of each pillar of the first iris sheet has a first rounded corner, and the top of each pillar of the second iris sheet has a second rounded corner, The first rounded corner is greater than or equal to the second rounded corner. The display device as claimed in claim 11, further comprising: a first bonding layer disposed between the first chrome sheet and the second rim sheet, wherein: the second rim sheet comprises a plurality of first rims pillars and a plurality of second pillars; the height of the first pillars is greater than the height of the second pillars; and the tips of the first pillars are in conflict with the first adhering layer. The display device of claim 17, wherein the sum of the lengths of the projections of the first pillars in the first direction accounts for the first pillars and the second pillars in the first direction. The sum of the lengths of the projections in the first direction is 25% to 60%. The display device according to claim 11, further comprising: a second bonding layer disposed between the light-diffusing film and the first wafer, wherein: the wafer structure of the first wafer comprises a plurality of Three pillars and a plurality of fourth pillars; the height of the third pillars is greater than the height of the fourth pillars; and the tips of the third pillars and the second bonding layer conflict. The display device according to claim 19, wherein the sum of the lengths of the projections of the third pillars in the second direction accounts for the total length of the third pillars and the fourth pillars in the second direction. The sum of the lengths of the projections in the second direction is 25% to 60%.

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