Active stylus

An active stylus, including a housing, a pen core, a first circuit board, and a touch sensing module, is provided. The pen core, the first circuit board, and the touch sensing module are disposed in the housing. The touch sensing module includes a touch sensing element and a second circuit board. The touch sensing element is disposed on and electrically connected to the second circuit board. The second circuit board is electrically connected to the first circuit board and is abutted to a lateral surface of the first circuit board. The second circuit board is perpendicular to the first circuit board. The pen core is abutted to the touch sensing element.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority benefit of Taiwan application serial no. 110121368, filed on Jun. 11, 2021. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.

BACKGROUND

Technical Field

The disclosure relates to an active stylus.

Description of Related Art

As technology advances and develops, various electronic devices on the market use touch panels or touch pads as operating interfaces. Users usually operate on the touch panels with their fingers, however, when sliding with a finger on the touch panel, the friction may be too much due to the large contact area of the finger, which is not suitable for massive or fast input, and may also cause touching by mistake, so the stylus is introduced.

Existing styluses can be divided into active stylus and passive stylus. The active stylus sends signals from the signal transmission circuit inside the pen, so that the corresponding touch panel (or touch pad) determines the coordinates and the contact force of the contacted position after receiving the signal.

Generally speaking, in the existing active styluses, a pen core is pressed against a touch sensing element to generate changes in capacitance value or resistor value, which generates a contact force signal accordingly. Then, the contact force signal is transmitted from the touch sensing element to the main circuit board of the active stylus by a wire, so that the processor on the main circuit board can process, discriminate, or transmit the signal.

However, as the technology of touch sensing elements advances, the amount of information that needs to be transmitted also multiplies, as a result, the above-mentioned wire cannot meet the signal transmission requirement of new touch sensing elements. At the same time, the wire needs to take up a certain space inside the active stylus, and the bridge connection status between the wire and the circuit board also causes the assembly and welding to be difficult or easily damaged during the operation. Therefore, how to improve the electrical connection between the touch sensing element and the main circuit board so as to overcome the above challenges has become a topic of study for persons skilled in the art.

SUMMARY

The disclosure provides an active stylus, which provides a greater amount of information transmission by means of an electrical connection structure between circuit boards, and also provides connection structural strength.

The active stylus of the disclosure includes a housing and a pen core, a first circuit board, and a touch sensing module disposed in the housing. The touch sensing module includes a touch sensing element and a second circuit board. The touch sensing element is disposed on and electrically connected to the second circuit board. The second circuit board is electrically connected to the first circuit board and is abutted to a lateral surface of the first circuit board. The second circuit board is perpendicular to the first circuit board. The pen core is abutted to the touch sensing element.

In an embodiment of the disclosure, the first circuit board has an upper surface and a lower surface opposite to each other. The lateral surface is adjacent between the upper surface and the lower surface. The second circuit board has a front surface and a back surface opposite to each other. The back surface is abutted to the lateral surface. The touch sensing element is disposed on the front surface.

In an embodiment of the disclosure, the active stylus further includes multiple first pads and multiple second pads. The first pads are disposed on the upper surface and the lower surface respectively, and the second pads are disposed on the back surface. The first circuit board and the second circuit board are electrically connected to each other only by welding the first pads onto the second pads respectively.

In an embodiment of the disclosure, electrical signal pins of the first pads include seven of a serial data output (SDO), a serial data input/output (SDA), an input/output power supply (VDD_IO), an empty connection (NC), an interrupt signal1(INT1), an interrupt signal2(INT2), a power supply (VDD), an input/output ground (GND_IO), a ground (GND), a chip select (CSB), and a clock (SCL/SCLK), and electrical signal pins of the second pads correspond to the electrical signal pins of the first pads.

In an embodiment of the disclosure, each of the first pads maintains a distance relative to the lateral surface.

In an embodiment of the disclosure, a part of the first pads are arranged into a row (R1) on the upper surface, and another part of the first pads are arranged into a row (R2) on the lower surface. The second pads are arranged into a row (R3) and a row (R4) on the back surface. The first pads located in the row (R1) are welded correspondingly onto the second pads located in the row (R3) respectively, and the first pads located in the row (R2) are welded correspondingly onto the second pads located in the row (R4) respectively.

In an embodiment of the disclosure, the row (R1), the row (R2), the row (R3), and the row (R4) are parallel to each other.

In an embodiment of the disclosure, each of the second pads partially overlaps with the lateral surface.

In an embodiment of the disclosure, a pressure receiving direction of the touch sensing element is orthogonal to the front surface, the back surface, and the lateral surface.

In an embodiment of the disclosure, the pen core, the touch sensing element, and the lateral surface of the second circuit board are aligned with each other.

Based on the above, in the active stylus, the second circuit board of the touch sensing module is electrically connected to the first circuit board, and the second circuit board is structurally abutted to the lateral surface of the first circuit board to be perpendicular to each other. The touch sensing element is disposed on the second circuit board and back against the first circuit board, and the pen core is abutted to the touch sensing element. In this way, the component abutting relationship of the pen core, the touch sensing element, the second circuit board, and the first circuit board is formed sequentially in the active stylus. In addition to forming a smooth board-to-board electrical connection, the first and second circuit boards, which are perpendicularly connected to each other can also improve the structural strength. Especially for the touch sensing element, when the pen core is abutted to the touch sensing element, the second circuit board is supported by the first circuit board, so that the entire structure is not deformed or even damaged by the pressing action.

DESCRIPTION OF THE EMBODIMENTS

FIG.1is an exploded view of an active stylus according to an embodiment of the disclosure.FIG.2is a schematic view of an assembly of a touch sensing module and a first circuit board ofFIG.1. Referring toFIG.1andFIG.2together, in this embodiment, an active stylus100includes a housing110, and a pen core120, a touch sensing module130, a control module140, and a battery150disposed in the housing110. The housing110includes a front housing114, an upper housing112, a lower housing111, and a pen barrel113. One end of the control module140is electrically connected to the battery150, the touch sensing module130is electrically connected to the other end of the control module140. The pen core120, the touch sensing module130, and the control module140are clamped and fixed by the upper housing112and the lower housing111, and then sleeved by the pen barrel113. The front housing114is then locked to the pen barrel113, such that the front end of the pen core120protrudes from the front housing114and is movable along an axial direction to complete the general structural assembly of the active stylus100.

Furthermore, the control module140includes a first circuit board141, and a processor142, a switching element143, and other electronic elements (not shown) disposed thereon. The first circuit board141has an upper surface S1, a lower surface S2, and a lateral surface S3. The lateral surface S3is adjacent between the upper surface S1and the lower surface S2. The touch sensing module130includes a touch sensing element131and a second circuit board132. The second circuit board132has a front surface S5and a back surface S4opposite to each other. The touch sensing element131is disposed on and electrically connected to the front surface S5of the second circuit board132, and the touch sensing module130is abutted to the lateral surface S3of the first circuit board141with the back surface S4to complete the electrical connection relationship with the first circuit board141.

FIG.3illustrates the touch sensing module ofFIG.2from another perspective. Referring toFIG.1toFIG.3together, in this embodiment, since the second circuit board132is abutted to the lateral surface S3of the first circuit board141by the back surface S4thereof, the first circuit board141and the second circuit board132are perpendicular (orthogonal) to each other. At the same time, the touch sensing element131located on the front surface S5is substantially back against the first circuit board141, and the pen core120is facing a pressing convex portion131aof the touch sensing element131, so that the pen core120, the touch sensing element131, and the lateral surface S3of the first circuit board141are aligned with each other inside the active stylus100. In other words, the orthographic projections of the pen core120and the pressing convex portion131aof the touch sensing element131overlap with each other on the lateral surface S3, so that the pressing direction of the pen core120to the touch sensing element131(equivalent to the pressure receiving direction of the touch sensing element131) is orthogonal to the front surface S5and the back surface S4of the second circuit board132and the lateral surface S3of the first circuit board141.

In this way, the first circuit board141can serve as a structural support for the second circuit board132, so that the second circuit board132is not deformed or even damaged when the touch sensing element131is being pressed.

FIG.4andFIG.5illustrate a corresponding connection status between the first circuit board and the touch sensing module from another perspective. Referring toFIG.3toFIG.5together, in this embodiment, the active stylus100further includes multiple first pads B1to B7and multiple second pads A1to A7. The first pads B1to B7are disposed on the upper surface S1and the lower surface S2of the first circuit board141respectively. The second pads A1to A7are all disposed on the back surface S4of the second circuit board132. Referring toFIG.2toFIG.5, in this embodiment, the first circuit board141and the second circuit board132are electrically connected to each other only by welding the first pads B1to B7onto the second pads A1to A7respectively.

Referring toFIG.4andFIG.5, among the first pads B1to B7, a part of the first pads B1to B3are arranged into a row R1on the upper surface S1, while the other part of the first pads B4to B7are arranged into a row R2on the lower surface S2. The second pads A1to A7are all arranged into rows R3and R4on the back surface S4of the second circuit board132. The first pads B1to B3located in the row R1are welded correspondingly onto the second pads A1to A3located in the row R3respectively, and the first pads B4to B7located in the row R2are welded correspondingly onto the second pads A4to A7located in the row R4respectively. The row R1, the row R2, the row R3, and the row R4are parallel to each other.

At the same time, the touch sensing element131of this embodiment is a digital output touch sensing element formed by a capacitive MEMS structure, so multiple transmission ends are required to facilitate the transmission of a large amount of information. Accordingly, electrical signal pins of the first pads B1to B7of this embodiment include seven of a serial data output (SDO), a serial data input/output (SDA), an input/output power supply (VDD_IO), an empty connection (NC), an interrupt signal1(INT1), an interrupt signal2(INT2), a power supply (VDD), an input/output ground (GND_I)), a ground (GND), a chip select (CSB), and a clock (SCL/SCLK), while electrical signal pins of the second pads A1to A7are consistent corresponding to the electrical signal pins of the first pads B1to B7.

Referring toFIG.4again, for smooth electrical connection between the first circuit board141and the second circuit board132perpendicular to each other, in this embodiment, each of the first pads B1to B7maintains a distance D1relative to the lateral surface S3, and each of the second pads A1to A7partially overlaps with the lateral surface S3, so that the first pads B1to B7and the second pads A1to A7can be smoothly connected to each other in a one-to-one correspondence through a welding material170(FIG.4is a partially enlarged view with the first pad B3and the second pad A3as an example, the rest of the first pads B1, B2, and B4to B7, and the second pads A1, A2, and A4to A7are also the same, so there will be no repetition). At the same time, short circuit of the first pads B1to B7of the same group or the second pads A1to A7of the same group is also avoided.

To sum up, in the active stylus of the above embodiments of the disclosure, the second circuit board of the touch sensing module is electrically connected to the first circuit board, and the second circuit board is structurally abutted to the lateral surface of the first circuit board to be perpendicular to each other. The touch sensing element is disposed on the second circuit board and back against the first circuit board, and the pen core is abutted to the touch sensing element, so that the pen core, the force sensing element, and the lateral surface of the first circuit board are aligned with each other, which effectively improves the structural strength. When the pen core is abutted to the touch sensing element, the second circuit board is supported by the first circuit board, so that the entire structure is not deformed or even damaged by the pressing action.

Furthermore, the touch sensing element is a digital output touch sensing element formed by a capacitive MEMS structure, so multiple transmission ends are required to facilitate the transmission of a large amount of information. Therefore, by disposing multiple first pads on the upper surface and the lower surface of the first circuit board, the first pads are one-to-one welded onto multiple second pads on the back surface of the second circuit board. That is to say, during the process of board-to-board perpendicular connection of the disclosure, the pads are welded to each other to complete and meet the requirements of electrical connection.