CN203909327U - Display structure possessing high brightness diffuse reflector and electrowetting display device - Google Patents

Abstract

The utility model discloses a display structure with a high-brightness diffuse reflector and an electrowetting display device. The display structure includes a panel glass, a display layer, and a base glass, wherein a high-brightness diffuse reflection polymer is arranged under the base glass Film material, panel glass, display layer, base glass and diffuse reflective polymer film material are stacked in sequence. The electrowetting display device includes an electrowetting display device based on the display structure and an in-cell type electrowetting display device. In the display structure of the utility model, a high-brightness diffuse reflection polymer film is placed under the base of the flat panel display structure or under the display layer as a diffuse reflection layer or reflector to provide required diffuse reflection and contrast close to paper. Compared with the vacuum coating process, it is simpler and avoids the expensive vacuum coating process, which greatly reduces the production cost.

Description

A display structure with a high-brightness diffuse reflector and an electrowetting display device

technical field

The utility model relates to a display structure and a display device, in particular to a display structure with a high-brightness diffuse reflector and an electric wetting display device. the

Background technique

At present, the display unit used for text, image, video and interactive interface generally adopts flat panel display structure. In this field, widely used are, for example, microfluidic display system (Electro fluidic display system, EFD), electrophoretic display System (Electrophoretic display system), plane switching (In-Plane-Switching, IPS), electro-osmosis display system (Elctro-osmosis display system), and liquid crystal display LCD, etc. Some of the display structures use reflective displays, for example, EFD applied to electronic ink (E ink) or electronic paper. EFD can also be called electrowetting display (Electrowetting display). Electrowetting refers to changing the wettability of the droplet on the substrate by changing the voltage between the droplet and the insulating substrate, that is, changing the contact angle to make the droplet occur. The phenomenon of deformation and displacement. The so-called wetting refers to the process in which one fluid on a solid surface is replaced by another fluid. The liquid can spread on the solid surface, and the solid-liquid contact surface tends to expand, that is, the adhesion force of the liquid to the solid surface is greater than its cohesive force, which is wetting. The liquid cannot spread on the solid surface, and the contact surface tends to shrink into a spherical shape, that is, it is not wet, and the non-wet means that the adhesion force of the liquid to the solid surface is less than its cohesive force. The wetting effect of water-resistant surfaces can be altered using an electrical voltage (hence the name electrowetting), making the surface more hydrophilic (wetting). As the previously hydrophobic surface now becomes more water-absorbent, an inert liquid that was previously in good contact with the hydrophobic surface, such as an oil layer, has to change its form. This interface property control is fundamental for electrowetting applications. The application of the electrowetting display principle is described in detail in the patent WO03071347 and in the publication 425383385 of "Nature". the

Compared to other display technologies, EFD display technology and its structure have many advantages because of its high photoelectric efficiency and switching speed at the same time. The EFD unit is essentially a variable aperture filter. In the voltage-driven on state, its visual appearance is determined by the reflective material that reveals itself as the colored oil layer fades. A good reflective material can provide a better diffuse reflection effect for the display unit, so as to restore the user's simulation effect of reading on paper, and at the same time, provide a better contrast ratio. the

In the existing electronic paper, the realization of transparent EPD requires the principle of lateral driving. In transparent displays, Al and Ag coatings are usually applied on the bottom glass to form a mirror or reflective surface, which is quite different from paper. the

At present, the display screens that realize paper-like simulation effects on the market include Sony, Amazon kindle, etc., which are called electronic ink or electronic paper display screens, which are based on the principle of electrophoretic display (EPD), and are generally based on the vertical or vertical display of EPD. The driving principle is implemented as a reflective (non-transparent) display system. Its paper effect is achieved by using a vacuum coating process on the substrate, for example, by spraying TiO2 particles to form a coating. Although the purpose of TiO2 coating is to approximate the effect of paper as much as possible, its reflectivity is low, the contrast is not high, and the cost is high. the

Utility model content

The purpose of the utility model is to overcome the defects of the prior art problems, and provide a display structure with a high-brightness diffuse reflector and an electrowetting display device. the

In order to achieve the above object, the utility model adopts the following technical solutions:

According to one aspect of the present invention, a display structure with a high-brightness diffuse reflector is proposed. The display structure includes a panel glass, a display layer, and a base glass, wherein a reflector is arranged under the base glass, and the panel glass, The display layer, the base glass and the diffuse reflection polymer film material are laminated in sequence, wherein the reflector is the diffuse reflection polymer film material. the

Preferably, the diffuse reflection polymer film material is a PET-based material, and its thickness is set at 175um-350um. the

Preferably, the diffuse reflective polymer film material is filled with diffuse reflective particles, which are arranged to cause diffuse reflection of incident light. the

Preferably, the base glass is set to be thin enough to reduce the optical path between the display layer and the reflector; an adhesive layer is arranged between the base glass and the diffuse reflection polymer film material, which is used for diffuse reflection A polymeric film material is bonded to the substrate side of the display structure, the optical properties of the bonding layer being adapted to transmit incident light and outgoing light through the bonding layer. the

According to another aspect of the present utility model, an electrowetting display device is proposed. The electrowetting display device uses the aforementioned display structure with a high-brightness diffuse reflector, wherein the display layer is an EFD switching layer. the

According to yet another aspect of the present utility model, an electrowetting display device is proposed. The electrowetting display device includes a front panel, an EFD switching layer, and a reflector. The front panel, the EFD switching layer, and the reflector are stacked in sequence, wherein the The front panel includes panel glass or film, and the reflector is a PET-based diffuse reflective polymer film material. the

Preferably, the diffusely reflective polymer film material is a PET-based material, and the diffusely reflective polymer film material is filled with diffusely reflective particles arranged to diffusely reflect incident light. the

The display structure according to the present invention can be used in any non-transparent display technology, including but not limited to electrowetting display system, microfluidic display system, electrophoretic display system, planar switching display, electroosmotic display system, and liquid crystal display. the

Compared with the prior art, the utility model has the following significant advantages and beneficial effects:

According to the display structure and display device of the present invention, a diffuse reflective polymer film is placed under the base of the existing display structure as a reflector to provide the required diffuse reflectance and contrast close to paper. A polymer film containing diffuse reflection particles is integrated behind the transparent display panel or on the back of the substrate, thus realizing an electronic display that completely inherits traditional paper. Through proper configuration, the film material can reflect up to 93% of ambient light. This is much higher than paper (about 80%). Compared with the existing vacuum coating process, such as applying TiO2 coating, the manufacturing process adopted by the utility model is much simpler than the vacuum coating process, which avoids the expensive vacuum coating process and greatly reduces the production cost. the

Description of drawings

Below in conjunction with accompanying drawing, the embodiment of the utility model is described in detail:

Figures 1a and 1b are schematic diagrams of the principle of an electrowetting display device, wherein: 13, pixel wall, 14, substrate, 15, transparent electrode;

Figure 2 is a schematic diagram of a display structure according to an embodiment of the present utility model;

Figure 3 is a schematic diagram of a display structure according to another embodiment of the present utility model;

FIG. 4 is a schematic diagram of a display device according to yet another embodiment of the present invention. the

Detailed ways

The application of the electrowetting display principle is described in detail in the patent WO03071347 and in the publication 425383385 of "Nature". Its schematic structural diagrams are shown in Figures 1a and 1b. Figure 1a shows that when no voltage V is applied, the colored oil layer 11 completely covers the hydrophobic coating 12; Figure 1b shows that after the voltage V is applied, the colored oil layer 11 is covered. Push to the side. When a voltage V is applied on the electrode, the charge accumulates on the lower surface of the water layer 10, and then its electrostatic force F _el overcomes the capacitive force F _cap to break down the colored oil layer 11, covering the hydrophobic coating 12 on the substrate, making the water layer 10 is brought into contact with the otherwise hydrophobic coating under the action of a voltage V. By further increasing the voltage V, the breakdown colored oil layer 11 can be pushed to a corner of the pixel area. If the voltage V is removed, the compressed oil will return to the state before the voltage V was applied.

As shown in FIG. 2 , it is an embodiment of a display structure with a high-brightness diffuse reflector according to the present invention. The display structure includes a panel glass 1 , a display layer 2 , and a base glass 3 . In the existing reflective display technology, in order to obtain a diffuse emission effect, a diffuse reflection layer or a Lambertian reflector material needs to be disposed under the base glass 3 . However, in this embodiment, the diffuse reflection polymer film material 4 is arranged under the base glass 3 , and the panel glass 1 , the display layer 2 , the base glass 3 and the diffuse reflection polymer film material 4 are laminated in sequence. The diffuse reflective polymer film acts as a reflector and is arranged to diffusely reflect incident light 5 . In order to improve durability and reliability, preferably, the polymer film material requires low light transmittance, that is, has sufficient thickness, and in addition, has a certain physical strength, such as having sufficient wear resistance and tear resistance, to To meet the needs of the process, and to meet the reflective display, such as the contrast and diffuse reflection required by electronic paper. the

In order to obtain a good diffuse reflection effect and sufficient contrast to achieve a viewing effect close to paper, as an example, the diffuse reflection polymer film material 4 adopts Melinex329, Melinex339 material, or a film material with extremely high diffuse reflection , Melinex materials are based on PET, filled with diffuse reflective particles, such as BaTiO ₃ . They reflect up to 93% of ambient light, which is much higher than paper (approximately 80%), thereby achieving diffuse reflection with high brightness. As a reflector, the thickness of the film can be 175-350um, preferably 175 or 350um, which is thicker than ordinary paper, and this is one of the reasons for the improvement of optical properties.

As shown in Figure 3, it is another embodiment of the display structure with a high-brightness diffuse reflector according to the present invention. When the display layer 2 is in the light-transmitting "on" state, the incident light 5 passes through the panel glass 1, The display layer 2 and the base glass 3 are then reflected on the reflector, that is, the surface of the diffuse reflective polymer film material 4 , and the outgoing light 6 is emitted out of the panel glass 1 through the original optical path. In the above display structure, the key problem to be solved is to reduce the distance between the display layer 2 and the reflector, so as to improve the optical efficiency of the flat panel display structure with an external thin film material reflector. If the distance is too large, the refraction effect between different media will become obvious, which will limit the effective resolution of the display and the fineness of the display due to the optical distortion caused by refraction. Therefore, based on the required display resolution or fineness, this embodiment processes the base glass 3 thinner on the basis of the previous embodiment, so that the optical distance between the display layer 2 and the reflector can be reduced. For example, the thickness of the base glass 3 of the display structure is preferably set to be less than 0.5 mm, more preferably less than 0.2 mm. the

To further improve the optical performance, the paper reflector can be bonded to the base side of the display structure using an adhesive layer 7 with suitable optical properties. On the basis of the foregoing embodiments, an adhesive layer 7 is provided between the base glass 3 and the diffuse reflection polymer film material 4, which is used to bond the diffuse reflection polymer film material 4 to the substrate of the display structure side. The optical properties of the adhesive layer 7 are adapted such that incident light rays 5 and outgoing light rays 6 penetrate the adhesive layer 7 . the

According to the manufacturing method of the display structure with a high-brightness diffuse reflector of the present invention, it comprises the following steps: a display layer 2 is arranged on a base glass 3; a panel glass 1 is arranged on the display layer 2; An adhesive layer 7 is arranged on one side of the display layer 2; a diffuse reflective polymer film material 4 is arranged on the side of the adhesive layer 7 away from the base glass 3, wherein the optical properties of the adhesive layer 7 are suitable for It is configured to allow incident light 5 and outgoing light 6 to pass through said adhesive layer 7 . For example, the thickness of the base glass 3 can be set to be less than 0.5 mm, more preferably less than 0.2 mm. Preferably, the diffuse reflective polymer film material 4 is used as a reflector and arranged to diffusely reflect incident light 5 . the

The above-mentioned display structure with a high-brightness diffuse reflector according to the present invention can be applied to various flat panel display devices, especially reflective display devices and/or flexible display devices. Based on the display principle, mechanical characteristics and manufacturing process of the electrowetting display unit, the display structure with a high-brightness diffuse reflector according to the present invention is especially suitable for the electrowetting display unit. the

As shown in Figure 4, it is an electrowetting display device with a high-brightness diffuse reflector according to the present invention, and its specific stacked structure is similar to the above-mentioned display structure with a high-brightness diffuse reflector, in the electrowetting display device , the display layer 2 is an EFD switching layer 9 , and an example of the specific structure of the EFD switching layer 9 can be referred to in FIG. 1 . In fact, the display structure of the present invention can cooperate well with the electrowetting display technology to provide an excellent paper-like display effect. the

According to this embodiment, the further advantage of applying the polymer film reflector to the electrowetting display device is that its front panel can be directly processed on the polymer film as the reflector, and such a polymer film structure can be called in- The overall structure of the cell diffuser (diffuser) can be called an in-cell electrowetting display device. The front panel part may comprise a panel glass 1 or a front panel film 8 , and an EFD switching layer 9 . The front panel film 8 of such a front panel part can be manufactured based on a solution process, and a film material that is inert to the liquid used in the process and stable at the process temperature can be used, for example, Melinex329 or Melinex339 can be used. The simplified optical stack structure is shown in Figure 4. the

This structure is very efficient because now the reflector is directly adjacent to the switching optical layer. Standard PET has good dimensional stability up to about 120 degrees Celsius. Dupont Teijin has announced a new thermally stable grade of PET that can withstand process temperatures as high as 180 degrees Celsius. In cases where higher process temperatures are required, PEN substrates can be used, which are more costly but commercially available. the

The display structure and manufacturing method according to the present invention can be used in any non-transparent display technology, including but not limited to electrowetting display system, microfluidic display system, electrophoretic display system, plane conversion display, electroosmosis display system, and liquid crystal show. the

The above is only a preferred embodiment of the utility model, and the utility model is not limited to the above-mentioned embodiment, as long as it achieves the technical effect of the utility model by the same means, it should belong to the protection scope of the utility model. Various modifications and changes can be made to the technical solutions and/or implementations within the protection scope of the present utility model. Even if individual technical features are cited in different claims, the invention may also include embodiments sharing these features. the

Claims (7)

1. A display structure with a high-brightness diffuse reflector, characterized in that, the display structure comprises panel glass, display layer, base glass, wherein, a reflector is arranged under the base glass, panel glass, display layer, base The glass and the diffuse reflective polymer film material are laminated sequentially, wherein the reflector is the diffuse reflective polymer film material. the 2 . The display structure with a high-brightness diffuse reflector according to claim 1 , wherein the diffuse reflective polymer film material is a PET-based material, and its thickness is set to 175um-350um. the 3. A display structure with a high-brightness diffuse reflector according to claim 2, characterized in that the diffuse reflective polymer film material is filled with diffuse reflective particles, which are arranged to cause diffuse reflection of incident light. the 4. A display structure with a high-brightness diffuse reflector according to claim 1, wherein the base glass is set to be thin enough to reduce the optical path between the display layer and the reflector; the base An adhesive layer is provided between the glass and the diffusely reflective polymer film material for bonding the diffusely reflective polymer film material to the substrate side of the display structure, the optical properties of the adhesive layer being adapted to make the incident Light and exit light pass through the adhesive layer. the 5. An electrowetting display device, characterized in that the electrowetting display device uses the display structure with a high-brightness diffuse reflector according to any one of claims 1-4, wherein the display layer is EFD Switch layers. the 6. An electrowetting display device, characterized in that the electrowetting display device comprises a front panel, an EFD switching layer and a reflector, and the front panel, the EFD switching layer and the reflector are stacked in sequence, wherein the front panel comprises a panel Glass or film, the reflector is a PET based diffuse reflective polymer film material. the 7. An electrowetting display device according to claim 6, wherein the diffuse reflection polymer film material is a PET-based material, and the diffuse reflection polymer film material is filled with diffuse reflection particles, which are set In order to make the incident light produce diffuse reflection. the