351 may include a plurality of branches 351a and a plurality of branches 351b, the branches 351a and the branches 351b may be alternately arranged in sequence and respectively extend along different directions (for example a direction D4 and a direction D5, but not limited thereto). Then, the signal lines 351 may be disposed in the spacing between the sub-pixel 151, the sub-pixel 153 and the sub-pixel 155. In other words, the signal lines 351 may include a zig-zag structure. In one embodiment, the plurality of branches 351a may also extend along several different directions, but not limited thereto. The signal lines 351 may include different lengths in the second direction D2 to connect electrically to different sensing electrodes 310. For example, a signal line 351 may electrically connect to one of the sensing electrodes 310 that is adjacent to the driving circuit 330, another signal line 351 may electrically connect to another sensing electrode 310, and the two signal lines 351 may include different lengths in the second direction D2, but is not limited thereto. An angle θ1 between the direction D4 and the direction D5 is for example between zero degree to 90 degrees (0°≤θ1≤90°), such as 30 degrees or 60 degrees, but not limited thereto. In one embodiment, an angle θ2 between the signal lines 351 and the extending direction (for example the first direction D1) of the bending axis “A” may be greater than zero degree and less than or equal to 90 degrees (0°≤θ2≤90°), for example being 30 degrees, 45 degrees, 60 degrees or 75 degrees, but not limited thereto.

Person skilled in the art should easily understand that while disposing the signal lines 350 in the spacing between the sub-pixel 151, the sub-pixel 153 and the sub-pixel 155, the disposing structure of the signal lines 350 is not limited to the aforementioned zig-zag structure and may further include other types. For example, in another embodiment, a plurality of branches 353a and a plurality of branches 353b of at least one of the signal lines 353 may also be continuously arranged side by side and extend in different directions (for example the direction D4 and the direction D5) at the same time, and the signal lines 353 may generally present a mesh structure. Accordingly, the corresponding sub-pixel 151, the corresponding sub-pixel 153 or the corresponding sub-pixel 155 may be exposed from mesh portions 353m or mesh portions 353n that are consisted by the branches 353a and the branches 353b. In other words, the signal lines 353 may include a plurality of openings for exposing the sub-pixel 151, the sub-pixel 153 or the sub-pixel 155, so that, one of the openings may be corresponded to at least one of the sub-pixel 151, the sub-pixel 153 and the sub-pixel 155. Also, the branch(es) 353a and the branch(es) 353b may constitute a complete mesh portion 353m, or may also constitute an incomplete mesh portion 353n, so that, the signal lines 353 may contact to the corresponding sensing electrodes 310 through the complete mesh portions 353m or the incomplete mesh portions 353n thereof. In some embodiments, since the signal lines 350 and the sensing electrodes 310 are disposed in different layers, the signal lines 350 may include at least one contact portion (such as two contact portions, not shown in the drawings), or at least two contact portions (such as more than two contact portions, not shown in the drawings) electrically connected to one of the sensing electrodes 310. For example, the contact portion may include a through hole or other electrical connection structure, but not limited thereto. It may include an angle between different portions of the signal lines 353 and the extending direction of the bending axis “A”, such as the angle θ2 or the angle θ3, and the angle may be greater than zero degree and less than or equal to 90 degrees (0°<θ2 or θ3≤90°, such as 30 degrees, 45 degrees, 60 degrees, 75 degrees or 90 degrees, but not limited thereto. It is noted that, although the signal lines 350 are all exemplified as a regular zig-zap structure (with the size of each sharp portion and each concave portion of the zig-zap structure being substantially the same with each other) or a regular mesh structure (with the size of each mesh portion of the mesh structure being substantially the same with each other) in each of the aforementioned embodiments, the practical fabricating process of the signal lines 350 is not limited thereto. The branches of the signal lines may also have more than two extending directions under different disposing requirements to present an irregular zig-zag structure or an irregular mesh structure.

On the other hand, as shown in FIG. 5, the sensing electrodes 310 may also include various aspects according to practical disposing requirements. For example, in one embodiment, a distribution density of at least a portion of the sensing electrodes 311 is for example about 25 to 50 sensing electrodes per square millimeter (25-50 items/mm²), such as 30 or 40 sensing electrodes per square millimeter. Then, the sensing electrodes 311 may have a relatively greater spacing G1 therebetween, for example, being about 30 μm to 50 μm (30 μm≤G1≤50 μm), such as 35 μm or 45 μm, but not limited thereto. The spacing G1 may be the smallest distance between two adjacent sensing electrodes 311. Accordingly, a portion of the sub-pixel 151, the sub-pixel 153 or the sub-pixel 155 may be disposed at the spacing G1 between the sensing electrodes 311, thereby being exposed therefrom, as shown in FIG. 5. In this way, while the signal lines 350 (as shown in FIG. 3 and FIG. 4) are provided to electrically connect the sensing electrodes 311, the signal lines 350 may obtain a relative greater process window thereby. On the other hand, another portion of the sensing electrodes 313 may optionally include a relatively greater distribution density, for example the distribution density being increased to about 100 to 400 per square millimeter (100-400 items/mm²), that is, a spacing G2 between the sensing electrodes 313 is shrunken for example to about 5 μm to 10 μm (5 μm≤G2≤10 μm), such as being 7 μm, but not limited thereto. The spacing G2 may be the smallest distance between two adjacent sensing electrodes 313. Accordingly, since the spacing G2 between the sensing electrodes 313 is smaller, the sub-pixel 151, the sub-pixel 153 or the sub-pixel 155 may not be exposed therefrom. Then, the disposing of the sensing electrodes 313 may be more compact to improve the resolution of the fingerprint sensor 300. Also, a portion of the sensing electrodes 315 may be optionally formed into a metal mesh structure, with traces being formed by metal with good conductivity (such as gold, silver, copper, aluminum, tungsten or an alloy of above metal, but not limited thereto) to form at least a portion of the sensing electrodes 315. In other words, the sensing electrodes 315 may further include a plurality of mesh portions 315m, which also includes a plurality of openings for exposing the sub-pixel 151, the sub-pixel 153 or the sub-pixel 155, and the sub-pixel 151, the sub-pixel 153 or the sub-pixel 155 may be disposed within the openings of the mesh portions 315m to be exposed therefrom. In this way, the influences to the display brightness of the pixel array 150 caused by the sensing electrodes 315 may be reduced. Person skilled in the art should realize that although the present embodiment may include the sensing electrodes 311, the second electrodes 313 and the sensing electrodes 315 with various types at the same time, the practical arrangement is not limited thereto. In other embodiments, a single type of the sensing electrodes may be optionally disposed based on the product requirements, for example, only disposing the sensing electrodes 315 to reduce the influences to the display brightness, or only disposing the sensing electrodes 313 to improve the resolution, or only disposing the sensing electrodes 311 to improve the processing window of the wires, but not limited thereto. The advantages of the above mentioned sensing electrodes are only for example, and which may actually have more or other advantages, and the present disclosure is not limited thereto.

In addition, as shown in FIG. 6 and FIG. 7, in another embodiment, the fingerprint sensor 300 may further include a plurality of first sensing electrodes 317a and a plurality of second sensing electrodes 317b, to form a mutual-capacitive electrode array. For example, one of the first sensing electrode 317a and the second sensing electrode 317b may be a driving electrode, and the other one of the first sensing electrode 317a and the second sensing electrode 317b may be a sensing electrode. It is noted that, FIG. 6 and FIG. 7 only illustrate a partial cross-sectional view of the electronic device. Precisely speaking, the first sensing electrodes 317a and the second sensing electrodes 371b may be two electrode layers, which are formed successively by similar or different processes, but not limited thereto. The first sensing electrodes 317a are for example parallelly arranged along a first axis (for example the first direction D1 as shown in FIG. 1), and the second sensing electrodes 317b are for example parallelly arranged along a second axis (for example the second direction D2 as shown in FIG. 1). The first sensing electrodes 317a and the second sensing electrodes 317b may be alternately arranged in another direction D6 that is different from the first direction D1 and the second direction D2, as shown in FIG. 6. The direction D6 for example has an angle of 45 degrees with the first direction D1 and the second direction D2, but is not limited thereto. Also, an insulating layer 320a and an insulating layer 320b may respectively cover on the first sensing electrodes 317a and the second sensing electrodes 317b, for isolating the first sensing electrodes 317a and the second sensing electrodes 317b. In other embodiments, the fingerprint sensor 300 may also include a self-capacitive electrode array, for example, only disposing the first sensing electrodes 317a or only disposing the second sensing electrodes 317b. As an example, only the first sensing electrodes 371a are disposed to provide driving and sensing function, but not limited thereto.

Moreover, as shown in FIG. 7, another substrate 340 may be further disposed between the first sensing electrodes 317a and the second sensing electrodes 317b, and the second sensing electrodes 317b may be disposed on the substrate 340. The material of the substrate 340 includes a dielectric material, an insulating material, or other suitable material, so that, the distance between the first sensing electrodes 317a and the second sensing electrodes 317b may be enlarged to reduce the parasitic capacitance between the first sensing electrodes 317a and the second sensing electrodes 317b to achieve better sensing signals thereby.

Through these arrangements, the issues that the flexible display 100 is frequently bent and used to affect the overall performance of the electronic device 10 may be improved. However, person skilled in the arts should easily realize the electronic device 10 of the present disclosure may also include another type of arrangement in order to meet the practical product requirement. The following description will detail the different embodiments of the electronic device in the present disclosure. To simplify the description, the description detail following will the dissimilarities among the different embodiments and the identical features will not be redundantly described. In order to compare the differences between the embodiments easily, the identical components in each of the following embodiments are marked with identical symbols.

Please refer to FIG. 8 to FIG. 10, which are schematic diagrams illustrating an electronic device 20 according to the second embodiment of the present disclosure, wherein FIG. 8 shows the disposing electrodes within the display substrate of the electronic device 20, and FIG. 9 and FIG. 10 show the appearance of the electronic device in bending mode. The structure of the electronic device 20 of the present embodiment is substantially the same as that of the aforementioned first embodiment, and, which also includes the flexible display 100 and the fingerprint sensor 300a disposed on the flexible display 100. All similarity between the present embodiment and the aforementioned embodiment will not be redundantly described hereinafter. The difference between the present embodiment and the aforementioned embodiment is mainly in that the distribution density of the electrode array of the fingerprint sensor 300a may be different in various regions.

Precisely speaking, as shown in FIG. 8, the flexible display 100 of the present embodiment also includes the flat region 111 and the bending region 113, and two opposite sides of the bending region 113 may be adjacent to two flat regions 111 respectively, but not limited thereto. In the present embodiment, a width W2 of the sensing electrodes 319b may be shrunken to for example about 20 μm to 30 μm (20 μm≤W2≤30 μm), such as 25 μm, so that, the distribution number of the sensing electrodes 319b per unit area may be increased, thereby performing a relative greater distribution density. In the present embodiment, the distribution density of the sensing electrode 319b within the bending region 113 may be greater than the distribution density of the sensing electrode 319a within the flat region 111. Then, the width W1 of the sensing electrodes 319a disposed in the flat region 111 may be different from the width W2 of the sensing electrodes