Patent Application
20230380252
The disclosure relates to the field of semiconductors technology, in particular to a display apparatus and a method for fabricating the display apparatus.
Fingerprint recognition takes characteristics that each person's fingerprint skin pattern and detail features are different and unique to confirm whether a fingerprint collection object is a target object by comparing a fingerprint of the collection object with pre-saved fingerprint data. Single-finger fingerprint recognition in a fixed area has been widely used in cell phones, and this kind of fingerprint module is generally a rigid fingerprint recognition module. For an organic display screen, the use of the rigid fingerprint module is limited due to the curvature of such screen. For better user experience, a fingerprint module needs to cooperate with the organic display screen to achieve flexible large-area fingerprint recognition without fixing an area.
An embodiment of the disclosure provides a display apparatus, including: a display panel including a display surface, and a back surface opposite to the display surface; a heat dissipation film, attached to the back surface of the display panel, the heat dissipation film having an opening area; and a flexible fingerprint recognition member on a side of the heat dissipation film facing away from the display panel. The flexible fingerprint recognition member includes: a fingerprint recognition component in the opening area, and a flexible heat dissipation component on a side of the fingerprint recognition component facing away from the display panel. The flexible heat dissipation component is provided with a first portion that covers the fingerprint recognition component, and a second portion that extends from the first portion, and the second portion overlaps the heat dissipation film at an edge of the opening area.
In a possible implementation, in a direction perpendicular to the display surface, a thickness of the flexible fingerprint recognition member in the opening area is greater than a thickness of the heat dissipation film, and the first portion and the second portions are connected in a Z-shaped mode at the lap joint where the second portion overlaps the heat dissipation film.
In a possible implementation, the flexible heat dissipation component includes: a copper foil, and a nano-carbon layer coated on a side of the copper foil facing the fingerprint recognition component.
In a possible implementation, the fingerprint recognition component includes: a flexible substrate, a functional layer on a side of the flexible substrate facing away from the flexible heat dissipation component; and an optical filter film on a side of the functional layer facing away from the flexible substrate.
In a possible implementation, the optical filter film is an infrared cutoff filter film, and the infrared cutoff filter film blocks light with a wavelength greater than 530 nanometers.
In a possible implementation, the fingerprint recognition component further includes: a collimating structure on a side of the optical filter film facing away from the functional layer.
In a possible implementation, the collimating structure includes a plurality of convex lenses distributed in an array, and a reflective layer on sides of the convex lenses facing the functional layer and having a plurality of via holes distributed in an array, the via holes are in one-to-one correspondence with the convex lenses, and the via hole and a center of the convex lens are located on a same straight line.
In a possible implementation, the via hole is located in a focus of the corresponding convex lens.
In a possible implementation, a projection of the convex lens on the flexible substrate is a hexagon.
In a possible implementation, the fingerprint recognition component further includes: an optical clear adhesive between the collimating structure and the optical filter film.
In a possible implementation, the fingerprint recognition component has a fingerprint recognition area, and a border area located on a periphery of the fingerprint recognition area. The fingerprint recognition component further includes: a frame adhesive on a side of the collimating structure facing the display panel, and the frame adhesive is located in the border area.
In a possible implementation, the fingerprint recognition component further includes: a double-sided adhesive tape between the flexible heat dissipation component and the fingerprint recognition component, and the flexible heat dissipation component and the fingerprint recognition component are bonded through the double-sided adhesive tape.
In a possible implementation, a projection of the first portion on the display surface is a rectangle, having a first side edge and a second side edge which are opposite, and a third side edge and a fourth side edge which are opposite; and the first side edge is bound with a first chip on film, and the fourth side edge is bound with a second chip on film. The second portion includes a first sub-heat dissipation portion extending from the second side edge, and a second sub-heat dissipation portion extending from the third side edge.
In a possible implementation, the first chip on film is provided with a fingerprint recognition chip; and the second chip on film is provided with a gate driving chip; and the second chip on film is further bonded with a flexible circuit board.
In a possible implementation, an area of the flexible fingerprint recognition member accounts for 40%-70% of an area of the display panel.
An embodiment of the disclosure further provides a method for fabricating the display apparatus provided by the embodiment of the disclosure, including: forming the flexible fingerprint recognition member; and attaching the flexible fingerprint recognition member to the opening area of the heat dissipation film on the back surface of the display panel. The forming the flexible fingerprint recognition member, includes: forming the fingerprint recognition component on a rigid substrate; stripping off the rigid substrate; and attaching a flexible heat dissipation component to a side of the fingerprint recognition component facing away from the display panel.
In a possible implementation, the forming the fingerprint recognition component on the rigid substrate includes: forming a functional layer on a bonding structure, where, the bonding structure includes the rigid substrate, and a flexible substrate bonded to the rigid substrate; forming an optical filter film on a side of the functional layer facing away from the flexible substrate; bonding a collimating structure to a side of the optical filter film facing away from the flexible substrate through an optical clear adhesive; and bonding a first chip on film and a second chip on film.
In order to make objectives, technical solutions and advantages of embodiments of the disclosure clearer, the technical solutions of the embodiments of the disclosure will be clearly and completely described below in conjunction with accompanying drawings of the embodiments of the disclosure. Apparently, the described embodiments are only a part of the embodiments of the disclosure, not all of the embodiments. Based on the described embodiments of the disclosure, all other embodiments obtained by those ordinarily skilled in the art without creative work shall fall within the protection scope of the disclosure.
Unless otherwise indicated, technical or scientific terms used in the disclosure shall have the ordinary meanings understood by those ordinarily skilled in the art to which the disclosure pertains. The words “first”, “second” and the like used in the disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. The words “comprise” or “include” or the like indicate that an element or item appearing before such words covers listed elements or items appearing after the words and equivalents thereof, and does not exclude other elements or items. The words “connect” or “couple” or the like are not limited to physical or mechanical connection, but may include electrical connection, whether direct or indirect. “Upper”, “lower”, “left”, “right” and the like are only used to represent relative position relationships, and the relative position relationships may also change accordingly after an absolute position of a described object is changed.
In order to keep the following descriptions of the embodiments of the disclosure clear and concise, detailed descriptions of known functions and known components are omitted.
Referring to
In the embodiment of the disclosure, the flexible fingerprint recognition member is arranged on the back surface of the display panel, and includes the first portion that covers the fingerprint recognition component, and the second portion that extends from the first portion, where, the second portions overlap a heat dissipation portion at the edges of the opening area. On the one hand, the flexible fingerprint recognition member is easy to bend, and may be surface-bonded and bent-bonded together with the curved display panel by using a soft-to-hard bonding technology, and the problem that in the prior art, a rigid fingerprint recognition member is limited in use and cannot achieve flexible large-area fingerprint recognition without a fixed area is improved. On the other hand, the second portions of the flexible heat dissipation component in the embodiment of the disclosure overlap the heat dissipation film at the edges of the opening area, which may make heat generated by the flexible fingerprint recognition member diffuse to the heat dissipation film in time, and may further improve the problem that a temperature will be too high and heat dissipation will be poor for long time use when realizing a large-area fingerprint recognition area.
During specific implementation, the display panel in the embodiment of the disclosure is the curved display panel shown in
During specific implementation, in a direction perpendicular to the display surface 11 (a direction along a dotted line CD in
During specific implementation, the flexible heat dissipation component 32 includes: copper foil, and a nano-carbon layer coated on a side of the copper foil facing the fingerprint recognition component 31, and a nano-carbon copper layer is formed. The copper foil is used for heat conduction, and the heat from the area where the fingerprint recognition component is located is conducted to the heat dissipation film 2. A heat conductivity may be 400 W/m·K. The nano-carbon layer may perform radiation heat dissipation. In the embodiment of the disclosure, the flexible heat dissipation component 32 includes: the copper foil, and the nano-carbon layer coated on the side of the copper foil facing the fingerprint recognition component 31. The nano-carbon copper layer itself has a certain hardness and may be bent. A strength of the flexible substrate (such as a PI film) of the fingerprint recognition component is increased after attaching the nano-carbon copper layer, and the nano-carbon copper layer may play a role of protecting the functional layer of the fingerprint recognition component, and meanwhile, the nano-carbon copper layer may also play a role of heat dissipation for a collection area of the fingerprint recognition component. Specifically, the flexible substrate (such as the PI film) of the fingerprint recognition component and the nano-carbon copper layer may be bonded together through double-sided adhesive tape. A thickness of the nano-carbon copper layer may be 80 um-120 um; or, it may be 90 um-110 um; specifically, it may also be 95 um-105 um; or, it may be 96 um; or, it may be 98 um; or, it may also be 100 um.
During specific implementation, in conjunction with
Specifically, the functional layer 311 in the fingerprint recognition component 31 may specifically include a plurality of recognition units distributed in an array. Each recognition unit may include: a first electrode and a second electrode arranged oppositely, and a photosensitive film layer located between the first electrode and the second electrode and used for photoelectric conversion.
During specific implementation, combined with
Specifically, a projection of the convex lens 3141 on the flexible substrate 310 is hexagon. The convex lens 3141 is of a hexagonal convex lens structure.
During specific implementation, in conjunction with
During specific implementation, the fingerprint recognition component 31 has a fingerprint recognition area, and a border area located on a periphery of the fingerprint recognition area. In conjunction with
During specific implementation, the fingerprint recognition component 31 further includes: double-sided adhesive tape between the flexible heat dissipation component 32 and the fingerprint recognition component 31, and the flexible heat dissipation component 32 and the fingerprint recognition component 31 are bonded through the double-sided adhesive tape.
During specific implementation, in conjunction with
During specific implementation, an area of the flexible fingerprint recognition member 3 accounts for 40%-70% of an area of the display panel 1. In the embodiment of the disclosure, the flexible fingerprint recognition member 3 and the display panel 1 are bonded and may be bent and folded, and at an edge position of the curved display panel, the flexible fingerprint recognition member 3 may be bent and bonded according to a curved surface of the display panel 1. The flexible fingerprint recognition member 3 is not affected by a bonding plane, and the fingerprint recognition area may be extended to the curved surface of the edge of the display panel 1, which increases the area of a fingerprint recognition module, so that the large-area fingerprint recognition of a half screen may be realized.
During specific implementation, in conjunction with
During specific implementation, materials of the fingerprint recognition component 31, except for the peripheral fingerprint recognition chip 411, the gate driving chip 421, and the element 51, are flexible materials. Specifically, the functional layer 311 in the fingerprint recognition component 31 may be a flexible film layer.
Based on the same inventive concept, an embodiment of the disclosure further provides a method for fabricating the display apparatus provided by the embodiment of the disclosure, referring to
For S100, the forming the flexible fingerprint recognition member, includes:
During specific implementation, for S110, the forming the fingerprint recognition component on the rigid substrate includes:
In order to understand the method for fabricating the display apparatus provided by the embodiment of the disclosure more clearly, a further detailed description is provided as follows.
Step 1, the functional layer 311 of the fingerprint recognition component 31 is fabricated on the bonding structure of the flexible substrate (the PI film) and the rigid substrate (such as a glass substrate) using a thin film transistor process, specifically, it may be the PI film on the top and the glass substrate on the bottom, the glass substrate protects the PI film during a fabricating process, a wire of the functional layer 311 is on the flexible PI film surface, the glass substrate plays a role of protecting the trace on the PI film to prevent the trace from breaking due to bending or expanding of the PI film during the production process. The thickness of the PI film may be 15 um or 38 um, preferably 15 um, and the thickness of the protective glass substrate is generally 0.5 mm or 0.7 mm, preferably 0.7 mm.
Step 2, after fabricated, the large functional layer 311 is cut into small pieces of fingerprint recognition sensors.
Step 3, each small piece of fingerprint recognition sensor is plated with an infrared cutoff filter film, and light with the wavelength greater than 530 nm is blocked and cannot enter the sensor functional layer.
Step 4, the optical clear adhesive 313 (OCA) is used to bond the collimating structure 314 on the fingerprint recognition sensors, and the optical clear adhesive 313 between the collimating structure 314 and the fingerprint recognition sensors is a disposed all over the surface; the thickness of the collimating structure 314 is generally 56 um, and the thickness of the optical clear adhesive 313 is generally 25 um, 75 um or 100 um, etc., preferably 25 um; and the optical clear adhesive 313 is a multilayer film, the array of hexagonal convex lenses 3141 is above the optical clear adhesive 313, and the reflective layer with an array of the transparent via holes 3142 is below the optical clear adhesive 313.
Step 5, the first chip on film 41, the second chip on film 42 and the flexible circuit board 5 are bonded to the fingerprint recognition sensors.
Step 6, after a fingerprint recognition sensor semi-finished module is fabricated, the protective layer of glass substrate needs to be stripped off.
Step 7, after the protective layer of glass substrate is stripped off, the flexible heat dissipation component 32 (the nano-carbon copper layer) needs to be attached to the PI film, the nano-carbon copper layer plays a role of heat dissipation and protection of the PI film functional layer, and the PI film layer and the nano-carbon copper layer are bonded together by double-sided adhesive tape. The thickness of the nano-carbon copper layer is generally 50 um or 100 um, preferably 100 um.
The above is the fabricating process of the flexible ultra-thin optical flexible fingerprint recognition component, each layer of film material has the above various thicknesses to choose from, and choosing the smallest thickness may make the optical fingerprint module to achieve an ultra-thin effect. In order to make the image collected by the flexible fingerprint recognition member be high in contrast and to achieve the ultra-thin effect, the thickness of each layer may be: the frame adhesive 315 may be 25 um, the collimating structure 314 may be 56 um, the optical clear adhesive 313 (OCA) may be 25 um, a sum of the thicknesses of flexible substrate 310 and the functional layer 311 may be 15 um, the optical filter film 312 (the infrared cutoff filter film) may be 5 um, the flexible heat dissipation component 32 (the nano-carbon copper layer) may be 100 um, and the total thickness of the flexible fingerprint recognition member 3 may be 226 um.
The beneficial effects of the embodiments of the disclosure are as follows: in the embodiments of the disclosure, the flexible fingerprint recognition member is arranged on the back surface of the display panel, and includes the first portion that covers the fingerprint recognition component, and the second portions that extend from the first portion, where, the second portions overlap the heat dissipation portion at the edges of the opening area. On the one hand, the flexible fingerprint recognition member is easy to bend, and may be surface-bonded and bent-bonded together with the curved display panel by using a soft-to-hard bonding technology, and the problem that in the prior art, a rigid fingerprint recognition member is limited in use and cannot achieve flexible large-area fingerprint recognition without a fixed area is improved. On the other hand, the second portions of the flexible heat dissipation component in the embodiments of the disclosure overlap the heat dissipation film at the edges of the opening area, which may make heat generated by the flexible fingerprint recognition member diffuse to the heat dissipation film in time, and may further improve the problem that a temperature will be too high and heat dissipation will be poor for long time use when realizing a large-area fingerprint recognition area.
Although the preferred embodiments of the disclosure have been described, those skilled in the art may make additional changes and modifications on these embodiments once they know the basic creative concept. So the appended claims are intended to be construed to include the preferred embodiments and all changes and modifications that fall into the scope of the disclosure.
Apparently, those skilled in the art may make various modifications and variations to the embodiments of the disclosure without departing from the spirit and scope of the embodiments of the disclosure. In this way, under the condition that these modifications and variations to the embodiments of the disclosure fall within the scope of the claims of the disclosure and their equivalent technologies, the disclosure is also intended to include these modifications and variations.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/CN2020/120204 | 10/10/2020 | WO |
