Optical film, display module and electronic equipment

Abstract

The invention provides an optical film, a display module and electronic equipment. The optical film comprises a peep-proof functional layer. The peep-proof functional layer comprises a plurality of shading parts which are arranged at intervals; the light shielding parts have a light shielding state, the light shielding parts are used for blocking light rays from penetrating in the light shielding state, and the light rays within the preset emitting angle can be emitted out through an interval between every two adjacent light shielding parts; parameters of one part of at least one shading part are different from parameters of other parts, and the parameters are parameters related to the grating diffraction effect and comprise at least one of the shape parameter of the single shading part, the size parameter of the single shading part and the distance parameter between every two adjacent shading parts. The grating diffraction effect correlation means that the change of the parameters can cause the change of the grating diffraction effect. The parameters are different and can be realized by changing the setting mode of the shading part, so that the grating diffraction effect of at least one area of the optical film can be weakened, and the pattern ghosting phenomenon of the optical film is further weakened.

Description

Technical Field

[0001] The present application relates to the display field, and in particular to an optical film, a display module and an electronic device. Background Art

[0002] With the development of society, people pay more and more attention to the privacy and security of electronic devices. This has also prompted the continuous development and improvement of Louver Array Film (LAF) technology. At present, most of the privacy films use ultra-fine louver structures. However, this kind of privacy film is prone to display ghosting problems. Summary of the invention

[0003] The present application provides an optical film, a display module and an electronic device, which improve the problem that the existing anti-peep film easily causes display ghosting.

[0004] In order to achieve the above purpose, this application adopts the following technical solutions:

[0005] In the first aspect, an optical film is provided. The optical film includes an anti-peeping functional layer. The anti-peeping functional layer includes a plurality of shading parts arranged at intervals. The shading part has at least a shading state, in which the shading part is used to block the passage of light, and the light within the preset emission angle can be emitted through the interval between two adjacent shading parts. Among them, the preset emission angle can be designed according to the needs of use, such as 0 to 50°, or 0 to 40°, etc. The parameters of a part of at least one shading part are different from the corresponding parameters of other shading parts, and the parameters are parameters related to the grating diffraction effect, including the shape parameters of a single shading part, the size parameters of a single shading part, and at least one of the spacing parameters between two adjacent shading parts. The above-mentioned correlation with the grating diffraction effect means that the change of the parameter can cause the change of the grating diffraction effect. Because the display ghosting is related to the grating diffraction effect generated when the light passes through the optical film.

[0006] The above-mentioned shading portion can form a grating structure, wherein two adjacent shading portions and the interval therebetween can form a grating unit in the grating structure. The optical film provided by the embodiment of the present application can break the periodicity of the grating units in the grating structure, so that the parameters of at least one grating unit in the grating structure are different from the parameters of other grating units, which can destroy the uniformity of the grating structure, and this non-uniform structure will change the scattering and interference pattern of the light wave when passing through the grating structure, so that when the light wave passes through the grating structure, the changes in its phase and amplitude will also become complicated, resulting in the light wave being unable to form a stable interference and diffraction pattern when passing through the grating structure. This non-uniform structure makes the propagation direction, amplitude and phase of the light wave after passing through the grating structure more dispersed and chaotic, thereby weakening the grating diffraction effect when the light passes through at least one grating unit of the optical film, thereby weakening the graphic ghosting phenomenon of the optical film, optimizing the display effect, and also alleviating the visual fatigue problem caused by long-term use of the optical film to a certain extent.

[0007] In some embodiments, the parameters include the spacing parameters between two adjacent shading parts. The spacing parameters between at least two adjacent shading parts are different from the spacing parameters between two other adjacent shading parts. In this way, the grating constant corresponding to at least one single slit in the grating structure-like structure formed by the shading part can be greater than the grating constants corresponding to other single slits, which can weaken the single slit diffraction effect when the light passes through the single slit with a larger grating constant to a certain extent, thereby weakening the grating diffraction effect of the light passing through the anti-peep film. And compared with the grating constant corresponding to only one grating unit being greater than the grating constant corresponding to other grating units, the solution provided by this embodiment can make the range of the grating diffraction effect weakened larger, and the ghosting phenomenon can be further weakened.

[0008] In some embodiments, the spacing parameter between at least two adjacent light shielding portions differs from the spacing parameter between two other adjacent light shielding portions by more than 2 micrometers. This facilitates the preparation and testing of the optical film.

[0009] In some embodiments, a plurality of groups of shading parts are provided, and the plurality of groups of shading parts are arranged at intervals. The structure of each group of shading parts is the same, and each group of shading parts includes a plurality of shading parts arranged at intervals. The spacing parameter between at least two adjacent shading parts in the same group is different from the spacing parameter between other two adjacent shading parts. In this solution, the width of the light channel varies periodically, and the spacing parameter between the shading parts also varies periodically. Compared with the irregular variation of the spacing parameter of the shading parts, the optical film can be easier to design and prepare.

[0010] In some embodiments, in the same group of light channels, the number of light channels is greater than or equal to three. This can provide more design options for the optical film, and through reasonable design, the grating diffraction effect of the optical film produced by this option can be weaker than that of the optical film corresponding to the option with only two different grating constants.

[0011] In some embodiments, in the same group of light channels, the spacing parameters between any two adjacent shading portions are different to weaken the grating diffraction effect.

[0012] In some embodiments, the parameters include the size parameters of a single shading portion, and the size parameters of a single shading portion include the height of the shading portion. In this way, the amount of light emitted from both sides of the light channel after the light passes through the same light channel can be different, and the emission angles are also different, so that the areas of the two overlapping regions of the light passing through the three light channels arranged in sequence can be different, which will affect the propagation mode and scattering characteristics of the light wave when passing through the grating, making the propagation direction, amplitude and phase of the light wave after passing through the grating more complex and dispersed. In addition, shading portions of different heights may cause multiple scattering and interference of the light wave when passing through the grating structure. The effect of multiple scattering and interference can further disperse the energy of the light wave and reduce the diffraction intensity in a specific direction. When the height difference of different shading portions is large enough, the complexity of this scattering and interference increases, which can weaken the grating diffraction effect of the light passing through the optical film to a certain extent, so that the display ghosting phenomenon is weakened.

[0013] In some embodiments, there are multiple groups of shading parts, each group of shading parts includes multiple shading parts arranged in sequence, and the height of at least one shading part in the same group of shading parts is different from the height of other shading parts. In this way, the light propagation conditions on both sides of the same light channel can be different, and the areas of the two overlapping areas of the light passing through the three light channels arranged in sequence can be different, which can reduce the grating diffraction effect of the light passing through the optical film to a certain extent, so that the display ghosting phenomenon is reduced. At the same time, the structure of each group of shading parts is the same, and the periodic arrangement of the shading parts can be realized, which is convenient for the design and preparation of the optical film.

[0014] In some embodiments, any two shading portions in the same group of shading portions have different heights, which can further reduce the grating diffraction effect of light passing through the optical film, thereby reducing the ghosting phenomenon of the display.

[0015] In some embodiments, in the same group of shading portions, the number of shading portions is greater than or equal to three, and the height difference between two shading portions with different heights is greater than 2 micrometers, so as to facilitate the preparation and inspection of the optical film.

[0016] In some embodiments, the parameters include shape parameters of a single shading portion, and the shape parameters of at least one shading portion are different from the shape parameters of other shading portions. By using the optical film provided in this embodiment, compared with the shape parameters of all shading portions being the same, the surface structure of the grating structure can be changed, so that the scattering and interference pattern of the light wave when passing through the grating structure is different from that of the traditional uniform grating structure, so that the energy of the light wave can be dispersed when passing through the grating structure, so that the distribution of the diffracted light in space is more uniform, and the diffraction intensity in a specific direction is reduced, so that the grating diffraction effect can be weakened to a certain extent, so that the display ghosting phenomenon is weakened.

[0017] In some embodiments, the extension trajectory of the light shielding portion in the length direction includes a curve and / or a broken line.

[0018] The optical film provided by this embodiment is changed in its surface structure compared to the shading portion extending in a straight line in the length direction, so that the scattering and interference pattern of the light wave when passing through is different from the traditional uniform grating structure, so that the light wave can disperse the energy of the light wave when passing through the grating structure, so that the distribution of the diffracted light in space is more uniform, and the diffraction intensity in a specific direction is reduced; secondly, the extension trajectory of the shading portion in the length direction is a curve or a broken line, so that the width of the grating unit of the grating structure in the length direction is no longer uniformly changed, but changes according to the shape of the curve or the broken line. This non-periodic structure destroys the periodicity of the grating structure, thereby weakening the diffraction effect to a certain extent. In addition, the extension trajectory of the shading portion in the length direction is a curve or a broken line, which may also introduce more scattering and interference effects. This complex interaction will further disperse the energy of the light wave and reduce the diffraction intensity in a specific direction, thereby weakening the grating diffraction effect to a certain extent, so that the display ghosting phenomenon is weakened.

[0019] In some embodiments, the light shielding portion includes straight line portions and folded line portions that are alternately arranged and connected. Compared with the light shielding portion extending in a straight line in the length direction, the light can be staggered after passing through different areas of the light channel, thereby weakening the grating extension effect to a certain extent and reducing the display ghosting phenomenon.

[0020] In some embodiments, the light shielding portion includes straight portions and curved portions that are alternately arranged and connected. Compared with the light shielding portion extending in a straight line in the length direction, the light can be staggered after passing through different areas of the light channel, thereby weakening the grating extension effect to a certain extent, and reducing the display ghosting phenomenon.

[0021] In some embodiments, the extension trajectory of the light shielding portion in the length direction satisfies a periodic function, which facilitates the design and preparation of the light shielding portion.

[0022] In some embodiments, the period of the extended track is 20 micrometers to 200 micrometers, and the amplitude is 2 micrometers to 20 micrometers. The above range is used to facilitate the design and preparation of the light shielding part, and can make the ghosting phenomenon of the optical film weaker.

[0023] In some embodiments, at least two shading portions are staggered in the periodic direction of the shading portions, so that the widths of different positions of the same light channel can be different, that is, the grating constants corresponding to different positions of the same light channel are different, thereby further weakening the grating diffraction effect and reducing the display ghosting phenomenon.

[0024] In some embodiments, the offset distance of at least two shading portions is less than or equal to half of the period, so that the grating constants corresponding to different regions of the light channel can be within a reasonable range and will not be too large or too small to affect normal display.

[0025] In some embodiments, the offset distance is 2 micrometers to 10 micrometers, so that the grating constants corresponding to different areas of the light channel can be within a reasonable range and will not be too large or too small to affect normal display.

[0026] In some embodiments, the cross-sectional shape of the light shielding portion is a trapezoid, a rectangle or a triangle, which can be prepared according to the use requirements. Among them, when the light shielding portion is a trapezoid, the light shielding effect is better and it is easy to prepare.

[0027] In some embodiments, the width of the middle position of the light shielding portion is 3 micrometers to 20 micrometers, so that the thickness of the light shielding portion is small, which does not affect the display effect, or has a small adverse effect on the display effect.

[0028] In some embodiments, the shading portion is made of at least one of black ink, electrochromic, electronic ink, and polymer dispersed liquid crystal. It is understandable that when the optical film is attached to the light-emitting surface of the display panel, the optical film is generally made of black ink. This can make the cost of the optical film lower, and there is no need to consider how to energize the optical film. When the optical film is integrated into the display panel, the optical film is generally made of electrochromic materials, electronic ink, polymer dispersed liquid crystal and other materials. This can make the optical film have at least two states, so that the optical film has more functions and helps to improve the user experience.

[0029] In some embodiments, the optical film further includes a protective layer attached to the light-emitting surface of the anti-peeping functional layer. In this way, the protective layer can protect the anti-peeping functional layer, reduce the risk of wear of the anti-peeping functional layer, and can increase the service life of the optical film to a certain extent, ensuring the stability of its performance.

[0030] In some embodiments, the protective layer includes a substrate and a protective functional layer sequentially arranged along the light emitting direction, and the protective functional layer includes a work hardening layer and / or an anti-fingerprint layer. The provision of the work hardening layer helps to improve the scratch resistance of the optical film. The provision of the anti-fingerprint layer helps to reduce the risk of fingerprints left on the surface of the optical film, which can improve the user experience to a certain extent.

[0031] In some embodiments, the refractive index of the substrate is 1.45-1.65, so that the light emission angle can meet the viewing requirements of users.

[0032] In a second aspect, a display module is provided. The display module includes a display panel and an optical film provided by any of the above schemes. The optical film can be attached to the light-emitting side of the display panel or integrated into the display panel, depending on the use requirements. The display module provided in the embodiment of the present application adopts the optical film provided by any of the above schemes, which can reduce the ghosting problem to a certain extent, optimize the display effect, and alleviate the visual fatigue problem caused by long-term use of the optical film.

[0033] In a third aspect, an electronic device is provided. The electronic device comprises a support device and a display module provided by any of the above solutions, wherein the display module is arranged on at least one side of the support device. The electronic device provided by this solution can reduce the ghosting problem to a certain extent, optimize the display effect, and alleviate the visual fatigue problem caused by long-term use of the optical film. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 The display effect of the optical film used in the relevant technology;

[0035] Figure 2 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application;

[0036] Figure 3 A schematic diagram of the structure of the electronic device provided in an embodiment of the present application after the display module is removed;

[0037] Figure 4 A schematic cross-sectional structure diagram of a display module provided in one embodiment of the present application;

[0038] Figure 5 A schematic diagram of the cross-sectional structure of the optical film provided in Example 1 of the present application;

[0039] Figure 6 A schematic diagram of the cross-sectional structure of an optical film provided in Example 2 of the present application;

[0040] Figure 7 This is a schematic diagram of the cross-sectional structure of the optical film provided in Example 3 of the present application;

[0041] Figure 8 A schematic diagram of the cross-sectional structure of an optical film provided in Example 4 of the present application;

[0042] Fig. 9 A schematic diagram of the cross-sectional structure of an optical film provided in Example 5 of the present application;

[0043] Fig.10 This is a schematic diagram of the cross-sectional structure of the optical film provided in Example 6 of the present application;

[0044] Fig.11 A schematic diagram of the cross-sectional structure of an optical film provided in one embodiment of the present application;

[0045] Fig.12 This is a schematic diagram of the cross-sectional structure of the optical film provided in Example 7 of the present application;

[0046] Fig.13 A schematic structural diagram of an extension track of a light shielding portion in a length direction of an optical film provided in an embodiment of the present application;

[0047] Fig.14 This is a schematic diagram of the cross-sectional structure of the optical film provided in Example 8 of the present application;

[0048] Fig.15 A partial cross-sectional schematic diagram of a possible implementation of the optical film provided in Example 9 of the present application;

[0049] Fig.16 A schematic diagram of a partial side view structure of a light shielding portion in another possible implementation of the optical film provided in Example 9 of the present application;

[0050] Fig.17 A schematic diagram of a partial cross-sectional structure of another possible implementation of the optical film provided in Example 9 of the present application;

[0051] Fig.18 A schematic diagram of the cross-sectional shape of the light-shielding portion of the optical film provided in an embodiment of the present application;

[0052] Fig.19 A schematic diagram of the width of the middle position of the light shielding portion of the optical film provided in an embodiment of the present application;

[0053] Fig. 20 A schematic diagram of the cross-sectional structure of a protective layer in an optical film provided in one embodiment of the present application;

[0054] Fig.21 A schematic diagram of the cross-sectional structure of a protective layer in an optical film provided in another embodiment of the present application;

[0055] Fig. 22 Schematic diagram comparing the diffraction efficiency (ghosting degree) of a conventional optical film and the optical film provided in Example 2 of the present application.

[0056] Description of reference numerals:

[0057] 10. Support device; 20. Battery; 30. Circuit board; 40. Display module; 41. Display panel; 42. Optical film; 42a. Anti-peeping functional layer; 42b. Protective layer; 43. Peelable adhesive;

[0058] 411, back plate; 412, shielding layer; 413, back film; 414, OLED panel; 415, polarizer; 416, optical adhesive; 417, protective glass; 418, avoidance structure; 421, light-transmitting layer; 422, light-shielding part; 423, light channel; 424, substrate; 425, protective functional layer;

[0059] 422a, first light shielding portion; 422b, second light shielding portion; 422c, third light shielding portion; 4221, straight line portion; 4222, broken line portion; 4223, curved line portion; 4251, work hardening layer; 4252, anti-fingerprint layer;

[0060] X, first direction; Y, second direction;

[0061] a, period of the curve; b, amplitude; c, offset distance; e, thickness of the light-transmitting layer; h, height of the shading part; f, width of the middle position of the shading part. DETAILED DESCRIPTION

[0062] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0063] In the description of the present application, it should be understood that the terms "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0064] In order to facilitate the clear description of the technical solutions of the embodiments of the present application, in the embodiments of the present application, the words "first", "second" and the like are used to distinguish the same items or similar items with substantially the same functions and effects. For example, the first limiting portion and the second limiting portion are only used to distinguish different limiting portions, and do not limit their order. Those skilled in the art can understand that the words "first", "second" and the like do not limit the quantity and execution order, and the words "first", "second" and the like do not necessarily limit them to be different.

[0065] It should be noted that, in this application, the words "in one embodiment" or "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described in this application as "in one embodiment" or "for example" should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of the words "in one embodiment" or "for example" is intended to present the relevant concepts in a specific way.

[0066] In this application, unless otherwise clearly specified and limited, the terms "connected", "connection" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0067] In order to make the objectives, technical solutions and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0068] With the development of society, electronic devices such as smart watches, mobile phones, and laptops are increasingly used in modern life, work, and communication. The privacy and security issues of electronic devices are also receiving more and more attention. This has also prompted the continuous development and improvement of optical film (Louver Array Film, LAF) technology. At present, most optical films use ultra-fine louver structures. When preparing this optical film, the grating structure of the transmission layer is generally formed on the base groove first, and then the absorption layer is filled in the gap of the grating structure, and finally UV (ultraviolet) is used for curing. The transmission unit (such as the above-mentioned grating structure) and the light absorption unit (such as the above-mentioned absorption layer) of the traditional optical film structure are arranged alternately in a periodic manner. The basic structure of the light absorption unit is a trapezoidal structure, and the ratio of the structure depth H to the width W of the transmission unit H / W is at least 1 or 1.75, or greater. Among them, the transmission unit and the light absorption unit are generally made of resin, and the resin refractive index N1 of the transmission unit and the resin refractive index N2 of the light absorption unit meet the following conditions: N2-N1=±0.005. In addition, the periodically alternating grating structure of the optical film may cause the light emitted by the sub-pixels of the display screen in the electronic device to have a grating diffraction effect, thereby causing a ghosting problem, such as Figure 1 As shown. It is understandable that Figure 1 (a) and (b) in the figure show two kinds of ghosting phenomena respectively. In addition, in other cases, the ghosting problem can also have other manifestations. Generally, the ghosting problem is more obvious when watching at an oblique angle.

[0069] In order to improve or at least partially improve the above problems, an embodiment of the present application provides an optical film, which includes an anti-peeping functional layer. The anti-peeping functional layer includes a plurality of shading portions arranged at intervals. The shading portion has a shading state, in which the shading portion is used to block the passage of light, and the light within the preset emission angle can be emitted through the interval between two adjacent shading portions. The parameters of a part of at least one shading portion are different from the corresponding parameters of other shading portions, and the parameters are parameters related to the grating diffraction effect, including at least one of the shape parameters of a single shading portion, the size parameters of a single shading portion, and the spacing parameters between two adjacent shading portions. Related to the grating diffraction effect means that the change of the parameters can cause the change of the grating diffraction effect. The display ghosting is related to the grating diffraction effect generated when the light passes through the optical film. By using the optical film provided by the embodiment of the present application, the grating diffraction effect when the light passes through at least one area of ​​the optical film can be weakened by the reasonable setting of the above parameters, thereby weakening the graphic ghosting phenomenon of the optical film and optimizing the display effect, which can alleviate the visual fatigue problem caused by long-term use of the optical film to a certain extent.

[0070] The optical film provided in the embodiment of the present application can be applied to a display module using the optical film and an electronic device having the display module. The electronic device can be a smart watch, a mobile phone, a tablet computer, a notebook computer, a PC (personal computer), a display, a monitor, a television, etc.

[0071] For ease of explanation and understanding, the following description takes a mobile phone as an example of an electronic device.

[0072] like Figure 2 As shown, Figure 2 The structure diagram of the electronic device provided in the embodiment of the present application is shown in FIG. The mobile phone generally includes a support device 10 and a display module 40. Figure 3 As shown, Figure 3 A schematic diagram of the structure of the electronic device provided in an embodiment of the present application after the display module is removed. In addition to the above-mentioned support device 10 and display module 40, the mobile phone may also include a battery 20 and a circuit board 30, a display module 40, etc., all of which are arranged on the support device 10. Among them, the support device 10 may include one or more frames. When the support device 10 includes multiple frames, two adjacent frames can be rotatably connected to the same shaft cover through a shaft structure. The ends of the two adjacent frames close to the shaft structure can be rotated around the shaft structure, so that the ends of the two frames away from the shaft structure can be relatively close to or relatively away from each other, so that the mobile phone can present different states such as folding or unfolding accordingly.

[0073] The number of batteries 20 can be determined according to the use requirements, such as setting one or more batteries 20 on each frame. The battery 20 and the display module 40 are generally electrically connected to the circuit board 30 to ensure the normal operation of the electronic device.

[0074] There are generally a plurality of circuit boards 30. Generally, each circuit board 30 is provided with electronic components, and the type and quantity of the electronic components can be determined according to the use requirements of the electronic device.

[0075] The display module 40 generally covers one side of the support device 10, and can be a flexible screen or a rigid screen, which can be determined according to the use requirements. For example, when the support device 10 includes multiple frames that can be folded or unfolded, the display module 40 can be a flexible screen, so that when the state of the support device 10 changes, the shape of the display module 40 can also be folded or unfolded accordingly as the position between adjacent frames changes; when the support device 10 includes only one frame, the display module 40 can be a rigid screen.

[0076] The display module 40 can be divided into many types, such as LED (Light Emitting Diode) / LCD (Liquid Crystal Display), OLED (Organic Light Emitting Diode; or, Organic Electrol inescence Display, organic light-emitting semiconductor), TN (Twisted Nematic, twisted nematic panel), VA (Vertical Alignment, multi-quadrant vertical alignment type), IPS (In-Plane-Switching, plane switching type), etc.

[0077] Regardless of the type, the display module 40 generally includes a display panel. Figure 4 As shown, Figure 4 Schematic diagram of the cross-sectional structure of a display module provided in an embodiment of the present application. In some embodiments, the display module 40 includes an optical film 42 in addition to the display panel 41. The optical film 42 can be attached to the light emitting surface of the display panel 41 and is also the display panel 41 away from the light emitting surface. Figure 3 The optical film 42 is a side of the support device 10 shown in the figure; it can also be integrated into the display panel 41. When the optical film 42 is attached to the light-emitting surface of the display panel 41, it can be bonded to the display panel 41 through the removable adhesive 43. This facilitates the replacement or removal of the optical film 42. The optical film 42 can be an anti-peep film, a film that can prevent side light leakage, or a film that can achieve other functions, depending on the specific needs.

[0078] For ease of understanding, the structure of the display module 40 and the attachment position of the optical film 42 are described by taking an example in which the backlight module of a display panel is an OLED module and the optical film 42 is attached to the light emitting surface of the display panel 41 .

[0079] like Figure 4 As shown, Figure 4 A schematic diagram of the cross-sectional structure of a display module provided in an embodiment of the present application. The display module 40 includes a back plate 411, a shielding layer 412 (Shielding Layer), a back film 413 (Back Film), an OLED panel 414, a polarizer 415 (Polarizer, POL), an optical adhesive 416 (Optically Clear Adhesive, OCA), a protective glass 417 and an optical film 42, which are stacked in sequence. Among them, the back plate 411, the shielding layer 412, the back film 413, the OLED panel 414, the polarizer 415, the optical adhesive 416, and the protective glass 417 constitute the display panel 41. The back plate 411 can be made of stainless steel or plastic, etc., which can be determined according to the specific needs of use. Among them, a avoidance structure 418 (such as a through hole, a notch, etc.) can be set on the back plate 411 and the shielding layer 412 to provide space for the installation of other structures (such as electronic components, mounting structures on the frame, etc.), which can be determined according to the specific needs of installation.

[0080] It is understandable that the display module whose backlight module is an OLED module may also adopt different Figure 4 When the display module 40 is of other types, the optical film 42 is attached at a similar position.

[0081] like Figure 5 As shown, Figure 5 Schematic diagram of the cross-sectional structure of the optical film provided in Example 1 of the present application. The present application provides an optical film 42. The optical film 42 includes an anti-peeping functional layer 42a. The anti-peeping functional layer 42a includes a plurality of light shielding portions 422 arranged at intervals. A light channel 423 for light to pass through is formed between two adjacent light shielding portions 422.

[0082] The light shielding portion 422 may be made of black ink, or may be made of at least one of electrochromic materials, electronic ink, polymer dispersed liquid crystal (PDLC), etc. When the light shielding portion 422 is made of black ink, the light shielding portion 422 has only one state, namely, the light shielding state. When the light shielding portion 422 is made of electrochromic materials, electronic ink, polymer dispersed liquid crystal, etc., the light shielding portion 422 generally has at least two states, one state is the light shielding state, which may also be called the anti-peeping state, and the other state is the light-transmitting state, which may also be called the shared state, and the above two states can be switched by turning the power on and off. In the light shielding state, the light shielding portion 422 is used to block the light from passing through; in the light-transmitting state, the light shielding portion 422 allows the light to pass through, and at this time, the light shielding portion 422 cooperates with the light-transmitting layer 421 for display.

[0083] It is understandable that when the optical film 42 is attached to the light-emitting surface of the display panel 41, the shading portion 422 is generally made of black ink. This can make the cost of the optical film 42 lower, and there is no need to consider how to energize the optical film 42. When the optical film 42 is integrated into the display panel 41, the shading portion 422 is generally made of materials such as electrochromic materials, electronic ink, polymer dispersed liquid crystal, etc. This can make the optical film 42 have at least two states, so that the optical film 42 has more functions, which helps to improve the user experience. Among them, the parameters of a part of at least one shading portion 422 are different from the corresponding parameters of other shading portions 422. The above parameters are parameters related to the grating diffraction effect, including the shape parameters of a single shading portion 422, the size parameters of a single shading portion 422, and at least one of the spacing parameters between two adjacent shading portions 422. The above-mentioned correlation with the grating diffraction effect means that the change of the parameters can cause the change of the grating diffraction effect.

[0084] The above-mentioned shape parameters refer to parameters that can be used to represent the shape of the shading portion 422, as well as parameters related to the grating diffraction effect, and can be specifically determined according to the shape of the shading portion 422. For example, when the cross section of the shading portion 422 is a rectangle, the above-mentioned shape parameters can be the aspect ratio of the cross section of the shading portion 422; when one side of the shading portion 422 is a curved surface, the above-mentioned shape parameters can be the radius of curvature of the curved surface, and so on. The above-mentioned size parameters refer to parameters that can be used to represent the size of the shading portion 422 in at least one direction, as well as parameters related to the grating diffraction effect, such as height, width, length, and so on. The above-mentioned spacing parameter between two adjacent shading portions 422 refers to a parameter that can be used to represent the spacing between two adjacent shading portions 422. Since the shading portion 422 is a three-dimensional structure, the widths of different regions of the shading portion 422 in the height direction may be different, which may cause the spacing between two adjacent shading portions 422 to have different values ​​in different regions. For example Figure 5As shown, the cross-section of the shading portion 422 is a trapezoid, and the interval space between two adjacent shading portions 422 is a three-dimensional space, and the spacing of the three-dimensional space gradually increases from bottom to top along the height direction of the shading portion 422. At this time, the above-mentioned spacing parameter can be the spacing at any position, such as the length of the bottom surface of the above-mentioned three-dimensional space, that is, the spacing between the bottom surfaces of two adjacent shading portions 422, or the length between the top surfaces of the above-mentioned three-dimensional space, that is, the spacing between the top surfaces of two adjacent shading portions 422, and so on. The specific details can be determined according to actual conditions.

[0085] In this embodiment, the multiple shading portions 422 can form a structure similar to a grating structure. For ease of description, the above structure is referred to as a grating structure. The above grating diffraction effect refers to the diffraction phenomenon that occurs when light passes through the grating structure formed by the above multiple shading portions 422. Its principle is based on Fresnel diffraction and Fraunhofer diffraction. Grating diffraction will disperse the incident light beam into several beams of light in multiple directions. The angles and intensities of these light beams are determined by the diffraction angle and the parameters of the grating structure. The parameters of the grating structure include grating constant, grating width, grating thickness, etc. The position and shape of the above diffraction fringes depend on the parameters of the grating structure and the wavelength, direction and other parameters of the incident light. In the present application, the change of the parameters of the shading portion 422 can cause the change of the corresponding parameters of the above-mentioned grating structure, such as the spacing parameter between two adjacent shading portions 422 is consistent with the change of the above-mentioned grating constant, that is, the grating constant becomes larger when the above-mentioned spacing parameter becomes larger, and the grating constant becomes smaller when the above-mentioned spacing parameter becomes smaller; the length of the shading portion 422 corresponds to the grating width, that is, the longer the shading portion 422 is, the larger the grating width is, and the shorter the shading portion 422 is, the smaller the grating width is; the height of the shading portion 422 corresponds to the grating thickness, that is, the larger the height of the shading portion 422 is, the larger the grating thickness is, and the smaller the height of the shading portion 422 is, the smaller the grating thickness is, and so on.

[0086] The light emitting principle of the mobile phone using the optical film 42 provided in the embodiment of the present application is as follows: Figure 5 As shown, the arrow in the optical film 42 in the figure indicates the propagation direction of the light:

[0087] The light emitted from the display panel 41 enters the optical film 42 , the light irradiating the light shielding portion 422 is blocked by the light shielding portion 422 (may be reflected or absorbed), and the light irradiating the light channel 423 is transmitted through the light-transmitting layer 421 and emitted.

[0088] In the above process, multiple shading parts 422 form a structure similar to a grating structure, that is, a grating diffraction effect generally occurs after the light passes through the light channel 423. Specifically, when the light passes through the light channel 423, a single-slit diffraction will be formed, and the light passing through multiple light channels 423 will form a multi-slit interference phenomenon. In the related art, the structure, size, and spacing of different shading parts are the same, so that the structural parameters of each grating unit in the grating structure formed by the shading part are consistent. When the light wave passes through a grating with equally spaced parallel lines, due to the periodicity of the grating structure, the light wave is scattered and interfered, forming a series of specific diffraction patterns, so that the grating diffraction effect is significant after the light passes through the light channel 423, and then the ghosting phenomenon of the pattern passing through the optical film 42 is obvious. The above-mentioned grating unit is composed of two adjacent shading parts 422 and the interval between them.

[0089] To this end, the optical film 42 provided in the embodiment of the present application changes the setting mode of the shading portion 422 so that the parameters of a part of at least one shading portion 422 are different from the parameters of other shading portions, which can break the periodicity of the grating unit in the grating structure, so that the parameters of at least one grating unit in the grating structure are different from the parameters of other grating units, which can destroy the uniformity of the grating structure, and this non-uniform structure will change the scattering and interference mode of the light wave when passing through the grating structure, so that when the light wave passes through the grating structure, the changes in its phase and amplitude will also become complicated, resulting in the light wave being unable to form a stable interference and diffraction pattern when passing through the grating structure. This non-uniform structure makes the propagation direction, amplitude and phase of the light wave after passing through the grating structure more dispersed and chaotic, thereby weakening the grating diffraction effect of the light when passing through at least one grating unit of the optical film 42, thereby weakening the graphic ghosting phenomenon of the optical film 42, optimizing the display effect, and also alleviating the visual fatigue problem caused by long-term use of the optical film 42 to a certain extent.

[0090] In addition, it should be noted that the optical film 42 provided in the present application can be used not only as an anti-peep film, but also as a film to prevent side light leakage. In addition, other functions can be achieved by setting other structures on the optical film 42, depending on the specific needs.

[0091] To achieve the above effects, the light shielding portion 422 may be arranged in a variety of ways. For ease of understanding, an example is given below:

[0092] Embodiment 1

[0093] like Figure 5As shown, in this embodiment, the structures and sizes of the shading parts 422 are the same, and the spacing parameters between at least two adjacent shading parts 422 are different from the spacing parameters between other adjacent shading parts 422. This will make the widths of at least two light channels 423 different. It can be understood that since the light channel 423 is formed between two oppositely arranged shading parts 422, the shading part 422 is a three-dimensional structure with a certain length, width, and height, and the light channel 423 is also a three-dimensional space with a certain length, width, and height, and since the shapes and sizes of different areas of the shading part 422 may be different, the width of the above-mentioned light channel 423 may be different in different areas. It should be noted that the different widths of the above-mentioned at least two light channels 423 refer to that the widths of the corresponding areas of the at least two light channels 423 are different, such as the widths of the same end of the at least two light channels 423 are different; or, the top surface widths of the at least two light channels 423 are different; or, the bottom surface widths of the at least two light channels 423 are different.

[0094] As mentioned above, the light shielding portion 422 can form a structure similar to a grating structure. Then, the different widths of the at least two light channels 423 will result in different grating constants corresponding to at least two grating units in the grating structure. For ease of description, the grating constant corresponding to the grating unit is referred to as the grating constant corresponding to the light channel 423. Figure 5 In the figure, the grating constant d1 corresponding to the light channel 423 between the two leftmost shading parts 422 is smaller than the grating constant d2 corresponding to the light channel 423 on the right. The above grating constant refers to the distance between reference lines at the same horizontal height in two adjacent light channels 423, wherein the reference line can be selected according to actual conditions, such as the center line in the extension direction of the light channel 423 can be selected as the reference line; or the connection line between the right side wall and the top surface of the left shading part 422 of the light channel 423 can be selected as the reference line, such as Figure 5 As shown; the connecting line between the left side wall and the top surface of the right side light shielding portion 422 of the light channel 423 can also be selected as the reference line, and of course other positions can also be selected as the reference line.

[0095] It can be understood that, in the present embodiment, among all the shading portions 422, only one of the shading portions 422 may have a spacing parameter different from the spacing parameter between an adjacent shading portion 422 and the other two adjacent shading portions 422, that is, the grating constant corresponding to only one light channel 423 is different from the grating constants corresponding to the other light channels 423; the spacing parameters between any two adjacent shading portions 422 may also be different, that is, the grating constants corresponding to any two light channels 423 are different; the spacing parameters between any two adjacent shading portions 422 in a part of the shading portions 422 may also be different, and the spacing parameters between any two adjacent shading portions 422 in other shading portions 422 may be the same; that is, the grating constants corresponding to a part of the light channels 423 are different, and the grating constants corresponding to another part of the light channels 423 are the same.

[0096] Regardless of which of the above settings is adopted, since the grating constant is an important parameter of the grating structure, a change in the grating constant will change the grating diffraction effect.

[0097] When preparing the optical film provided in this embodiment, the spacing parameters between at least one shading portion and the adjacent shading portions can be set differently, such as being increased. In this way, when the light passes through the light channel 423 with a larger width, the single-slit diffraction effect will be weakened, thereby weakening the grating diffraction effect of the light passing through the above-mentioned optical film 42, thereby weakening the display ghosting phenomenon, or even eliminating it.

[0098] Embodiment 2

[0099] On the basis of the first embodiment, in order to facilitate preparation, in this embodiment, multiple groups of light shielding parts 422 are provided. The structure of each group of light shielding parts 422 is the same. Figure 6 As shown, Figure 6 This is a schematic diagram of the cross-sectional structure of the optical film provided in Example 2 of the present application. In the figure, the two shading portions 422 in the area surrounded by the dotted frame A are a group. A light channel 423 is formed between the two shading portions 422 in the same group. The grating constant corresponding to the light channel 423 is recorded as d1. Multiple groups of shading portions 422 are arranged at intervals along the first direction X. A light channel 423 is formed between two adjacent groups of shading portions 422. The grating constant corresponding to the light channel 423 is recorded as d2. d2 is different from d1. It can be understood that the above-mentioned dotted frame is only an auxiliary line for easy understanding, not a structural line.

[0100] Understandably, Figure 6The dotted frame in the figure is an auxiliary line for facilitating understanding that several shading portions 422 are provided in a single group of shading portions 422, and is not a structural line. In this embodiment, the spacing parameters between the shading portions 422 change alternately. This non-uniform structure will change the scattering and interference pattern of the light wave when passing through the grating, destroy the periodic structure in the original uniform spacing grating structure, and cause the light wave to be unable to form a stable interference and diffraction pattern when passing through. This non-periodic structure makes the propagation direction, amplitude and phase of the light wave after passing through the grating structure more dispersed and chaotic, thereby weakening the diffraction effect. In addition, the grating structure with alternating spacing may also cause multiple scattering and interference of the light wave when passing through, further dispersing the energy of the light wave and reducing the diffraction intensity in a specific direction. This multiple scattering and interference effect will also weaken the grating diffraction effect. In addition, the preparation of the shading portion 422 requires the use of a mold that is adapted to the arrangement rule of the shading portion 422. The spacing parameters between the shading portions 422 change alternately. Compared with the irregular change of the spacing of the shading portions 422, the relevant mold can be convenient for design and production, thereby making the optical film 42 easier to design and prepare.

[0101] Embodiment 3

[0102] On the basis of the first embodiment, in order to facilitate preparation, in this embodiment, multiple groups of light shielding parts 422 are provided. The structure of each group of light shielding parts 422 is the same. Figure 7 As shown, Figure 7 This is a schematic diagram of the cross-sectional structure of the optical film provided in Example 3 of the present application, in which the three shading portions 422 in the area enclosed by the dotted frame B in the figure form a group. Two light channels 423 are formed between the three shading portions 422 in the same group, and the grating constants corresponding to the two light channels 423 are respectively recorded as d1 and d2. Multiple groups of shading portions 422 are arranged at intervals along the first direction X, and a light channel 423 is formed between two adjacent groups of shading portions 422. The grating constant corresponding to the light channel 423 is recorded as d3. At least two of d1, d2, and d3 are different. That is, d1 may be equal to d2 and different from d3; or d1 may be equal to d3 and different from d2; or d2 may be equal to d3 and different from d1; or d1, d2, and d3 may be different from each other, and the specific value may be determined according to the needs of use. When d1, d2, and d3 are different, through reasonable design, the grating diffraction effect of the optical film produced by this scheme can be made weaker than that of the optical film corresponding to the scheme with only two different grating constants.

[0103] In this embodiment, the spacing parameters between two adjacent shading portions 422 in the same group of shading portions vary periodically, and the width of the light channel 423 also varies periodically, which can destroy the uniformity of the grating structure to weaken the grating diffraction effect. Compared with the irregular variation of the spacing of the shading portions 422, the optical film can be easier to design and prepare.

[0104] It can be seen from the enlightenment of the second and third embodiments that, based on the first embodiment, for the convenience of preparation, each group of light shielding parts 422 can also be provided with four or more (including four) light shielding parts 422. The structure of each group of light shielding parts 422 is the same. As long as the widths of at least two light channels 423 are different, the above effect can also be achieved. The above schemes should also be within the protection scope of this application.

[0105] On the basis of the first to third embodiments, in order to facilitate preparation and detection, the spacing parameter between at least two adjacent shading portions 422 can differ from the spacing parameter between the other two adjacent shading portions 422 by more than or equal to 2 microns, that is, the grating constants corresponding to the two different light channels 423 can be greater than or equal to 2 microns, such as 2 microns, 3 microns, 4 microns, etc. In this way, light channels 423 of different widths can be prepared by existing preparation processes and equipment, without the need to use processes or equipment with higher preparation accuracy, which can make the preparation and detection of optical films easy to complete. It can be understood that if the difference is 1 micron, preparation and detection can be performed, and the spacing parameter between at least two adjacent shading portions 422 can also be selected to differ by 1 micron, which can be determined according to the light output effect and the preparation process.

[0106] Embodiment 4

[0107] like Figure 8 As shown, Figure 8 This is a schematic diagram of the cross-sectional structure of the optical film provided in the fourth embodiment of the present application. In this embodiment, the height of at least one shading portion 422 is different from the height of the other shading portions 422. In this way, the heights of the side walls on both sides of at least one light channel 423 are different. With the optical film provided in this embodiment, among the two shading portions 422 corresponding to the same light channel 423, the maximum light emission angle corresponding to the shading portion 422 with a lower height is generally greater than the maximum light emission angle corresponding to the shading portion 422 with a higher height. Figure 8 As shown, the height of one shading portion 422 is h1, and the height of the other shading portion 422 is h2, h1 is less than h2, the maximum light emission angle corresponding to the shading portion 422 with the height h1 is a, and the maximum light emission angle corresponding to the shading portion 422 with the height h2 is b, where a is greater than b. For example, a can be 20°, b can be 15°, a can be 9°, b can be 8°, etc.

[0108] In this way, the amount of light emitted from both sides of the light channel 423 after the light passes through the same light channel 423 can be different, and the angle of emission is also different, so that the areas of the two overlapping regions of the light passing through the three light channels 423 arranged in sequence can be different, which will affect the propagation mode and scattering characteristics of the light wave when passing through the grating, making the propagation direction, amplitude and phase of the light wave after passing through the grating more complex and dispersed. In addition, the shading parts 422 of different heights may cause multiple scattering and interference of the light wave when passing through the grating structure. The effect of this multiple scattering and interference can further disperse the energy of the light wave and reduce the diffraction intensity in a specific direction. When the height difference of different shading parts 422 is large enough, the complexity of this scattering and interference increases, which can weaken the grating diffraction effect of the light passing through the optical film 42 to a certain extent, so that the display ghosting phenomenon is weakened.

[0109] Embodiment 5

[0110] On the basis of the fourth embodiment, in this embodiment, a plurality of light shielding portions 422 are provided. Each group of light shielding portions 422 has the same structure. Fig. 9 As shown, Fig. 9 Schematic diagram of the cross-sectional structure of the optical film provided in Example 5 of the present application. Each group of light shielding portions 422 includes two light shielding portions 422 arranged in sequence. For ease of understanding, Fig. 9 A dotted frame C is added to indicate that the two light shielding parts 422 are a group. For ease of description, the two light shielding parts 422 in the same group are referred to as the first light shielding part 422a and the second light shielding part 422b. The height h2 of the first light shielding part 422a is different from the height h1 of the second light shielding part 422b. For example, the height of the first light shielding part 422a and the height of the second light shielding part 422b can differ by 2 microns, 3 microns, 4 microns, etc. In general, the height h2 of the first light shielding part 422a and the height h1 of the second light shielding part 422b differ by more than 2 microns, that is, |h1-h2|≥2 microns, so that light shielding parts of different heights can be prepared by existing preparation processes and equipment, without the need to use processes or equipment with higher preparation accuracy, which can make the preparation and detection of optical films easy to complete. If the difference between the two is 1 micron, they can be prepared and tested, and the height of the first light shielding part 422a and the height of the second light shielding part 422b can also be selected to differ by 1 micron, which can be determined according to the light output effect, preparation process, detection conditions, etc.

[0111] With the optical film 42 provided in this embodiment, since the height of the first light shielding portion 422a and the height of the second light shielding portion 422b in the same group are different, the light propagation conditions on both sides after the light passes through the light channel 423 between the first light shielding portion 422a and the second light shielding portion 422b can be different, and the areas of the two overlapping regions of the light passing through the three light channels 423 arranged in sequence can be different, which can reduce the grating diffraction effect of the light passing through the optical film 42 to a certain extent, so that the display ghosting phenomenon is reduced. At the same time, the structure of each group of light shielding portions is the same, that is, the first light shielding portion 422a and the second light shielding portion 422b are alternately arranged and arranged in a periodic manner, which is convenient for the design and preparation of the optical film.

[0112] Embodiment 6

[0113] On the basis of the fourth embodiment, in this embodiment, a plurality of light shielding portions 422 are provided. Each group of light shielding portions 422 has the same structure. Fig.10 As shown, Fig.10 Schematic diagram of the cross-sectional structure of the optical film provided in Example 6 of the present application. Each group of light shielding portions 422 includes three light shielding portions 422 arranged in sequence. For ease of understanding, Fig.10 A dotted frame D is added to indicate that the three light shielding portions 422 form a group. For ease of description, the three light shielding portions 422 that are in the same group are referred to below as the first light shielding portion 422a, the second light shielding portion 422b, and the third light shielding portion 422c. The heights of at least two of the first light shielding portion 422a, the second light shielding portion 422b, and the third light shielding portion 422c are different. For example, the heights of the first light shielding portion 422a and the third light shielding portion 422c are different; the heights of the second light shielding portion 422b and the third light shielding portion 422c are different; the heights of the first light shielding portion 422a, the second light shielding portion 422b, and the third light shielding portion 422c are different. The heights of two different light shielding portions 422 may differ by 2 microns, 3 microns, 4 microns, etc. In general, the heights of two different light shielding portions 422 differ by more than 2 microns, that is, Fig.10 In the embodiment, |h1-h2|≥2 microns, or |h2-h3|≥2 microns, or |h1-h3|≥2 microns. This facilitates preparation and testing. If the difference is 1 micron, preparation and testing can be performed. The heights of the two different light shielding parts 422 can also be selected to differ by 1 micron, which can be determined according to the light output effect, preparation process, testing conditions, etc.

[0114] By using the optical film 42 provided in this embodiment, the heights of at least two of the first light shielding portion 422a, the second light shielding portion 422b and the third light shielding portion 422c are different, so that the light propagation conditions on both sides after the light passes through the light channel 423 between the first light shielding portion 422a and the second light shielding portion 422b are different, and the areas of the three overlapping regions of the light passing through the three light channels 423 arranged in sequence are different, which can reduce the grating diffraction effect of the light passing through the optical film 42 to a certain extent, so that the display ghosting phenomenon is reduced. At the same time, the structure of each group of light shielding portions is the same, that is, the first light shielding portion 422a, the second light shielding portion 422b and the third light shielding portion 422c are arranged periodically, which is convenient for the design and preparation of the optical film.

[0115] According to the fifth and sixth embodiments, each group of light shielding parts 422 includes more than four light shielding parts 422, and at least two light shielding parts 422 in the same light shielding part 422 group have different heights, which can also achieve the above effect. The above scheme is also within the protection scope of this application.

[0116] In the above-mentioned embodiments 1 to 6, the extension track of the length direction of the light shielding portion 422 can be a straight line, such as the length direction of the light shielding portion 422 is parallel to the length direction of the optical film 42 (such as Fig.11 In addition, the extension track of the light shielding portion 422 in the length direction may also adopt other shapes, such as curves, broken lines, irregular lines, etc. For ease of understanding, examples are given below.

[0117] Embodiment 7

[0118] like Fig.12 As shown, Fig.12 This is a schematic diagram of the cross-sectional structure of the optical film provided in Example 7 of this application. The extension trajectory of the length direction of the light shielding portion 422 is a curve. In this embodiment, the curve may satisfy a periodic function or may not satisfy a periodic function, which may be determined according to the preparation process, light output requirements, etc.

[0119] The optical film 42 provided in this embodiment is used, compared with the shading portion 422 extending in a straight line in the length direction, which changes the surface structure of the grating structure, so that the scattering and interference mode of the light wave when passing through the grating structure is different from that of the traditional uniform grating structure, so that the light wave can disperse the energy of the light wave when passing through the grating structure, so that the distribution of the diffracted light in space is more uniform, and the diffraction intensity in a specific direction is reduced; secondly, the extension trajectory of the shading portion 422 in the length direction is a curve or a broken line, so that the width of the single slit of the grating structure in the length direction is no longer uniformly changed, but changes according to the shape of the curve or the broken line. This non-periodic structure destroys the periodicity of the grating structure, thereby weakening the diffraction effect to a certain extent. In addition, the extension trajectory of the shading portion 422 in the length direction is a curve or a broken line, which may also introduce more scattering and interference effects. This complex interaction will further disperse the energy of the light wave and reduce the diffraction intensity in a specific direction, thereby weakening the grating diffraction effect to a certain extent, so that the display ghosting phenomenon is weakened.

[0120] In some embodiments, the above curve satisfies a periodic function, such as a curve similar to a sine curve or a cosine curve, which facilitates the design and preparation of the light shielding portion.

[0121] The above curve is a periodic curve, the period a of the curve can be 20 microns to 200 microns, and the amplitude b can be 2 microns to 20 microns. The above range is convenient for designing and preparing the light shielding part, and can make the ghosting phenomenon of the optical film weaker.

[0122] In other embodiments, the period a and amplitude b of the curve may also adopt other values, which may be determined according to the light emitting effect and the processing technology. In addition, in other embodiments, the extension track of the length square of the light shielding portion 422 may also be set in other ways, such as Fig.13 As shown, Fig.13 Schematic diagram of the structure of the extension track of the length direction of the light shielding portion in the optical film provided in the embodiment of the present application. The extension track of the length direction of the light shielding portion 422 can be a broken line, such as Fig.13 Alternatively, the extension trajectory of the length of the shading portion 422 may be a path where straight lines and broken lines are alternately arranged, such as Fig.13 Alternatively, the extension track of the length of the shading portion 422 may be a path where straight lines and curves are alternately arranged, such as Fig.13As shown in (c); or, the extension track of the length direction of the light shielding portion 422 may have a straight line portion, a broken line portion, and a curved line portion. It can be understood that in the above embodiments, the extension track of the length direction of the light shielding portion 422 may also satisfy the periodic function, or may not satisfy the periodic function, which may be determined according to the preparation process, light output requirements, etc. When the extension track of the length direction of the light shielding portion 422 satisfies the periodic function, the light shielding portion 422 is easier to design and prepare.

[0123] Embodiment 8

[0124] like Fig.14 As shown, Fig.14 This is a schematic diagram of the cross-sectional structure of the optical film provided in Example 8 of the present application. Based on Example 7, the above curve in this embodiment satisfies a periodic function, and two adjacent light shielding portions 422 are staggered in the periodic direction of the curve. In this way, the widths of different positions of the same light channel 423 can be different, that is, the grating constants corresponding to different positions of the same light channel 423 are different, thereby further weakening the grating diffraction effect and reducing the display ghosting phenomenon.

[0125] The above-mentioned offset distance c can be less than half of the period a of the curve. For example, when the period a of the curve is 20 microns to 200 microns, the offset distance c can be 2 microns to 10 microns. In this way, the grating constants corresponding to different areas of the light channel can be within a reasonable range and will not be too large or too small to affect normal display.

[0126] It can be known from the seventh and eighth embodiments that a scheme of periodic grating arrangement with alternating amplitude similar to the above scheme should also be within the protection scope of the present application.

[0127] Embodiment 9

[0128] In this embodiment, the shape of at least one shading portion 422 may be different from the shapes of other shading portions 422. In this embodiment, the shading portions 422 with different shapes may have only local spacing parameters with adjacent shading portions 422 that are different from the spacing parameters with other regions with adjacent shading portions 422. Fig.15 As shown, Fig.15 This is a partial cross-sectional schematic diagram of a possible implementation of the optical film provided in Example 9 of the present application, in which the spacing parameter between the two light shielding portions 422 in the dotted frame E is smaller than the spacing parameter between the two light shielding portions 422 in the dotted frame F. In this way, the grating constant corresponding to a certain area of ​​at least one light channel 423 can be different from the grating constant corresponding to other areas, thereby achieving an effect similar to that of Example 1.

[0129] In this embodiment, the light shielding portion 422 with different shapes may have a height that is different from that of other regions in only a part of the portion. Fig.16 As shown, Fig.16 This is a partial side view of the structure of the light shielding portion in another possible implementation of the optical film provided in Example 9 of the present application, in which the height of the light shielding portion 422 is low in the middle and high on both sides. In this way, the height of a certain area of ​​at least one light shielding portion 422 can be different from the height of other areas, thereby achieving an effect similar to that of Example 4.

[0130] The light shielding parts 422 in this embodiment may also be arranged periodically using at least two light shielding parts 422 with different shapes. Fig.17 As shown, Fig.17 This is a partial cross-sectional structural diagram of another possible implementation of the optical film provided in Example 9 of the present application, in which two light shielding portions 422 of different shapes are alternately arranged, one of which is bent along a fold line, and the other is bent along a curve. In this way, the grating constants corresponding to at least two regions in the same light channel 423 can be different, thereby achieving an effect similar to that of Example 8.

[0131] It is understandable that any multiple non-conflicting solutions in the above-mentioned embodiments 1 to 9 can be combined with each other to form a new solution, such as combining embodiment 1 with embodiment 4, combining embodiment 3 with embodiment 8, combining embodiment 2, embodiment 5 and embodiment 7, etc., and the above solutions should all be within the protection scope of this application.

[0132] In the above embodiments, Fig.18 As shown, Fig.18 Schematic diagram of the cross-sectional shape of the light shielding portion in the optical film provided in the embodiment of the present application. The cross-sectional shape of the light shielding portion 422 may be a rectangle, a trapezoid, a triangle, an inverted triangle, etc. Among them, the trapezoid may be a regular trapezoid, such as a right-angled trapezoid, an isosceles trapezoid, etc., or an inverted trapezoid, such as an inverted right-angled trapezoid, an inverted isosceles trapezoid, etc. Among them, when the cross-sectional shape of the light shielding portion 422 adopts a trapezoid, the anti-peeping effect is better and it is easy to process. In some embodiments, the width f of the middle position of the light shielding portion 422 is 3 microns to 20 microns. Fig.19 As shown, Fig.19 Schematic diagram of the width of the middle position of the light shielding portion in the optical film provided in the embodiment of the present application. The width of the middle position refers to the width of the light shielding portion 422 on the center line perpendicular to the height direction, and is also the spacing parameter between the centers of the two waist surfaces when the cross-sectional shape of the light shielding portion 422 is an isosceles trapezoid, an isosceles triangle, etc. In this way, the thickness of the light shielding portion 422 can be relatively small, which does not affect the display effect, or has a relatively small adverse effect on the display effect.

[0133] Based on the above embodiments, Fig.17As shown, in order to make the surface of the optical film smooth, the optical film generally further includes a light-transmitting layer 421. The light-transmitting layer 421 is a layer for light to pass through, and can be a single-layer structure or a multi-layer structure, depending on the use requirements. The light-transmitting layer 421 can be made of the material used to prepare the above-mentioned transmission unit, such as resin, plastic, etc. The above-mentioned light-shielding portion 422 is arranged on the light-transmitting layer 421.

[0134] The thickness e of the light-transmitting layer is generally greater than the height of the light-shielding portion 422, which facilitates the preparation of the light-shielding portion 422 and can make the outer surface of the optical film 42 flat. For example, in some embodiments, the height of the light-shielding portion 422 is 40 microns to 150 microns, and the thickness e of the light-transmitting layer is 40 to 200 microns. In this way, not only can the above-mentioned effects be achieved, but also the thickness of the optical film 42 can be made smaller. Of course, in other embodiments, the height of the light-shielding portion 422 and the thickness e of the light-transmitting layer can also adopt other ranges, which can be determined according to the light-emitting effect, usage needs, etc.

[0135] In the above embodiments, the anti-peeping functional layer 42a can first prepare a light-transmitting layer 421, then grooves are made on the light-transmitting layer 421, and then black ink or the like is filled in the grooves to prepare the light-shielding portion 422. As in the second embodiment, a periodic pattern can be transferred onto the light-transmitting layer 421 to obtain a periodically arranged groove body.

[0136] In some embodiments, the refractive index of the light-transmitting layer is 1.4-1.7, so that the light emission angle can meet the viewing requirements of users.

[0137] In order to prolong the service life of the optical film 42, in some embodiments, as Figure 8 As shown, the optical film 42 further includes a protective layer 42b attached to the light-emitting surface of the anti-peeping functional layer 42a. In this way, the protective layer 42b can protect the anti-peeping functional layer 42a, reduce the risk of wear of the anti-peeping functional layer 42a, and can improve the service life of the optical film 42 to a certain extent, ensuring the stability of its performance.

[0138] The protective layer 42b may be a single-layer structure, and the material may be PET (Polyethyleneterephthalate), TPU (Thermoplastic polyurethanes), EPU (epoxy polyurethane), or other materials, which may be determined according to the use requirements. Fig. 20 As shown, Fig. 20A schematic diagram of the cross-sectional structure of a protective layer in an optical film provided in an embodiment of the present application. In some embodiments, the protective layer 42b includes a substrate 424 and a protective functional layer 425 arranged in sequence along the light emitting direction. The protective functional layer 425 can be arranged in a variety of ways, such as an anti-slip layer or a super-hydrophobic layer. The structure of the protective functional layer 425 can be selected according to the needs of use. The provision of the protective functional layer 425 can make the protective layer 42b more functional and can improve the user experience to a certain extent.

[0139] In some embodiments, the protective functional layer 425 includes a hardening layer 4251 and / or an anti-fingerprint layer 4252. It is understandable that the solution provided by this embodiment includes at least the following situations: first, the protective layer 42b includes a substrate 424 and a hardening layer 4251 arranged in sequence along the light emitting direction; second, the protective layer 42b includes a substrate 424 and an anti-fingerprint layer 4252 arranged in sequence along the light emitting direction; third, the protective layer 42b includes a substrate 424, a hardening layer 4251 and an anti-fingerprint layer 4252 arranged in sequence along the light emitting direction. Fig.21 shown.

[0140] The above-mentioned substrate can be made of PET, TPU, EPU and the like.

[0141] The provision of the work hardening layer 4251 helps to improve the scratch resistance of the optical film 42. The provision of the anti-fingerprint layer 4252 helps to reduce the risk of fingerprints remaining on the surface of the optical film 42, and can improve the user experience to a certain extent.

[0142] In some embodiments, the refractive index of the substrate 424 is 1.45-1.65, so that the light emission angle can meet the viewing requirements of users.

[0143] In order to achieve a better display effect, the removable adhesive 43 may be optical adhesive, the thickness of which may be between 15 micrometers and 75 micrometers, and the refractive index of which may be between 1.4 and 1.6.

[0144] In the above embodiments, through reasonable design, the shading portion can block the wide-angle light emitted by the display panel and only allow light within a certain angle range, such as 0 to 50°, to be emitted, thereby achieving a left-right or multi-directional anti-peeping effect.

[0145] In order to verify the above effect, the inventor simulated the diffraction efficiency (also known as the degree of ghosting) corresponding to the conventional optical film and the optical film 42 provided in the second embodiment. The results are as follows: Fig. 22 As shown. The conventional optical film adopts an ultra-fine louver structure, and the shading parts are arranged periodically with equal spacing. The spacing of the shading parts in the second embodiment changes alternately, and the other structures are the same.

[0146] The results show that the design of the alternating shading parts increases the grating constant (periodic spacing) of the grating structure formed by the shading parts to a certain extent. In this way, the optical film can significantly reduce the ratio of the 1st order diffraction efficiency to the 0th order diffraction efficiency when the viewing angle is tilted (0th order is the intrinsic image, and 1st order is the ghost image). Among them, the ghosting degree at 6 degrees and 26 degrees is reduced from 0.27 and 0.97 of the traditional design to 0.22 and 0.79, respectively, making the ghosting phenomenon milder.

[0147] Another embodiment of the present application provides a display module, which includes the optical film provided by any of the above embodiments.

[0148] As mentioned above, the display module provided in this embodiment can be of various types, generally including a display panel and an optical film. The optical film can be attached to the light emitting side of the display panel or integrated into the display panel, depending on the usage requirements.

[0149] The display module provided in the embodiment of the present application adopts the optical film provided in any of the above embodiments, which can reduce the ghosting problem to a certain extent, optimize the display effect, and alleviate the visual fatigue problem caused by long-term use of the optical film.

[0150] Another embodiment of the present application provides an electronic device, which includes the display module provided by any of the above embodiments.

[0151] As mentioned above, the electronic device provided in this embodiment may be a tablet computer, a television, etc., and the specific device may be determined according to usage requirements.

[0152] The electronic device provided in the embodiment of the present application adopts the above-mentioned display module, which can reduce the ghosting problem to a certain extent, optimize the display effect, and alleviate the visual fatigue problem caused by long-term use of optical films.

[0153] Finally, it should be noted that the above are only specific implementations of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the present application should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. An optical film, characterized in that: The invention comprises an anti-peeping functional layer, wherein the anti-peeping functional layer comprises a plurality of shading portions arranged at intervals; the shading portions have a shading state, in which the shading portions are used to block the passage of light, and light within a preset emission angle can be emitted through the interval between two adjacent shading portions; parameters of a part of at least one of the shading portions are different from corresponding parameters of other shading portions, and the parameters are parameters related to the grating diffraction effect, including shape parameters of a single shading portion, size parameters of a single shading portion, and at least one of the spacing parameters between two adjacent shading portions, and the parameter related to the grating diffraction effect means that changes in the parameters can cause changes in the grating diffraction effect.

2. The optical film according to claim 1, characterized in that: The parameters include the spacing parameters between two adjacent shading parts; The spacing parameter between at least two adjacent shading portions is different from the spacing parameter between other two adjacent shading portions.

3. The optical film according to claim 2, characterized in that: The spacing parameter between at least two adjacent shading portions differs from the spacing parameter between two other adjacent shading portions by more than 2 micrometers.

4. The optical film according to claim 2 or 3, characterized in that: There are multiple groups of light-shielding portions, which are arranged at intervals. The structures of each group of light-shielding portions are the same. Each group of light-shielding portions includes multiple light-shielding portions that are arranged at intervals. The spacing parameters between at least two adjacent light-shielding portions in the same group are different from the spacing parameters between other two adjacent light-shielding portions.

5. The optical film according to claim 4, characterized in that: In the same group of the shading parts, the number of the shading parts is greater than or equal to three.

6. The optical film according to claim 4 or 5, characterized in that: In the same group of the shading portions, the spacing parameters between any two adjacent shading portions are different.

7. The optical film according to any one of claims 1 to 6, characterized in that: The parameters include size parameters of a single light shielding portion, and the size parameters of a single light shielding portion include the height of the light shielding portion.

8. The optical film according to claim 7, characterized in that: The light shielding parts are provided in a plurality of groups, each group of the light shielding parts comprises a plurality of light shielding parts arranged in sequence, and the height of at least one light shielding part in the same group of the light shielding parts is different from the heights of the other light shielding parts.

9. The optical film according to claim 8, characterized in that: In the same group of the shading portions, the number of the shading portions is greater than or equal to three, and the heights of any two of the shading portions are different.

10. The optical film according to claim 8 or 9, characterized in that: In the same group of the shading portions, the height difference between the two shading portions with different heights is more than 2 micrometers.

11. The optical film according to any one of claims 1 to 10, characterized in that: The parameters include shape parameters of a single light shielding portion, and the shape parameter of at least one light shielding portion is different from the shape parameters of the other light shielding portions.

12. The optical film according to claim 11, characterized in that: The extension track of the light shielding portion in the length direction includes a curve and / or a broken line.

13. The optical film according to claim 11, characterized in that: The light shielding portion includes straight line portions and folded line portions which are alternately arranged and connected. Alternatively, the light shielding portion includes straight line portions and curved line portions that are alternately arranged and connected.

14. The optical film according to any one of claims 11 to 13, characterized in that: An extension trajectory of the light shielding portion in the length direction satisfies a periodic function.

15. The optical film according to claim 14, characterized in that: The period of the extended track is 20 microns to 200 microns, and the amplitude is 2 microns to 20 microns.

16. The optical film according to claim 14 or 15, characterized in that: At least two of the light shielding portions are staggered in a periodic direction of the light shielding portions.

17. The optical film according to claim 16, characterized in that: The offset distance between at least two of the shading portions is less than or equal to half of the period.

18. The optical film according to claim 17, characterized in that: The dislocation distance is 2 micrometers to 10 micrometers.

19. The optical film according to any one of claims 1 to 18, characterized in that: The cross-sectional shape of the light shielding portion is a trapezoid, a rectangle or a triangle; And / or, the width of the middle position of the light shielding portion is 3 micrometers to 20 micrometers; And / or, the shading portion is made of at least one of black ink, electrochromic ink, electronic ink, and polymer dispersed liquid crystal.

20. The optical film according to any one of claims 1 to 19, characterized in that: The optical film also includes a protective layer attached to the light-emitting surface of the anti-peeping functional layer.

21. The optical film according to claim 20, characterized in that: The protective layer comprises a substrate and a protective functional layer which are sequentially arranged along the light emitting direction, and the protective functional layer comprises a work hardening layer and / or an anti-fingerprint layer.

22. The optical film according to claim 21, characterized in that The refractive index of the substrate is 1.45-1.

65.

23. A display module, characterized in that: It comprises a display panel and the optical film according to any one of claims 1 to 22, wherein the optical film is attached to the light emitting surface of the display panel or integrated into the display panel.

24. An electronic device, characterized in that: It comprises a supporting device and the display module as claimed in claim 23, wherein the display module is arranged on at least one side of the supporting device.

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