JP2015032285A - Stylus pen used for touch panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide stylus pen used for a touch panel, the pen securing operability and having high impedance.SOLUTION: A stylus pen 1 used for a capacitive touch panel at least comprises a shaft cylinder 2 and a core part 3 formed from conductive material provided at a tip of the shaft cylinder. Impedance between a pen tip of the core part and a particular position of the shaft cylinder exceeds 5.5×10Ω and equal to or less than 1.6×10Ω at a measurement frequency of 1 kHz.

Description

  The present invention relates to a stylus pen used for a touch panel, and particularly to a stylus pen used for a capacitive touch panel.

In recent years, in portable information terminals such as smartphones and tablet PCs that are rapidly spreading, a projection capacitive touch panel capable of multi-touch operation is often used.
The structure of the projected capacitive touch panel will be briefly described with reference to FIG. 7 (exploded view). The capacitive touch panel 50 shown in FIG. 7 has an indium tin oxide film (hereinafter referred to as an ITO film) having a plurality of electrodes for detecting coordinates in the Y direction on the back side of a transparent insulating film 53, for example. 51 is formed, and an ITO film 52 having a plurality of electrodes for detecting coordinates in the X direction is formed on the front side.

The ITO film 51 is provided with a plurality of rhombic electrode pads 54 (sensor electrodes) connected in the X direction and electrically connected to each other in the Y direction, and the ITO film 52 is formed in the Y direction. A plurality of rhombic electrode pads 55 (sensor electrodes) connected to each other and electrically connected to each other are provided in a plurality of rows in the X direction. Each of the electrode pads 54 and 55 has an area sufficient to generate a change in capacitance (about 1 pF) that can detect the contact position of an indicator (such as a finger or a stylus pen). The width is about 5 mm.
When the insulating film 53 on which the ITO films 51 and 52 are formed is viewed in plan, the electrode pads 54 and 55 have a two-dimensional lattice structure in which the electrode pads 54 and 55 are arranged in the plane direction with a predetermined gap as shown in FIG. ing.

When, for example, a fingertip is brought into contact with a cover glass (not shown) disposed on the upper surface of the touch panel 50, the capacitance of the electrode pad 54 at the contact position among the electrode pads 54 connected in the X direction is increased. It changes to a predetermined value or more. Thereby, the coordinate position in the Y direction is detected.
In addition, among the electrode pads 55 connected in the Y direction, the capacitance of the electrode pad 55 at the contact position changes to a predetermined value or more. Thereby, the coordinate position in the X direction is detected.

By the way, the capacitance type touch panel 50 cannot detect the position unless the capacitance (about 1 pF) is changed more than a predetermined value at the contact point by the finger or the stylus pen as described above. .
For this reason, conventionally, for example, a conductive stylus pen that can be contacted with a contact area larger than the area of the electrode pads 54 and 55 has been used for the input operation to the capacitive touch panel, and the electrostatic capacity necessary for position detection is used. A change in capacitance is generated (if the contact area is small, a change in capacitance necessary for position detection does not occur).
For example, Patent Document 1 discloses a prior art regarding a projected capacitive touch panel.

  As a stylus pen, as shown in Patent Document 2, an input touch pen has been proposed which includes an input tip including a shaft tube and a fiber bundle core of conductive fibers.

JP 2008-310551 A JP 2013-50936 A

  By the way, the electrostatic capacitance generated between the upper surface of the cover glass and the electrode pad flows as a weak current (for example, 10 μA to 20 μA) to the human body via the stylus pen, whereby the contact position of the stylus pen nib is changed. Detected. Therefore, conventionally, many stylus pens are composed of conductive shafts.

However, in the previous application (Japanese Patent Application No. 2013-081766), the applicant of the present invention applied 10 ^{5 to} the surface of the cover glass for a touch panel while the operable pin gauge diameter in the conventional cover glass for a touch panel is 4 mm. ^When a film on which a transparent conductive thin film having a predetermined surface resistivity set within a range of ^0.0 to 10 ^8.0 Ω / sq is pasted, the touch panel reacts even with a pin gauge having a diameter of 3.7 mm. I found out that In other words, it has been found that the touch panel reacts even when the pin gauge diameter is reduced from 4 mm to 3.7 mm and the impedance is increased by increasing the electrical resistance.

  In this way, if a stylus pen having a large impedance can be used for the capacitive touch panel, for example, the content of the conductive material in the shaft cylinder of the stylus pen is reduced, or the outer peripheral surface of the shaft cylinder of the stylus pen is used. This greatly affects the structure and manufacturing method of the stylus pen, such as eliminating the need to provide a conductive layer of metal or the like, and thus the stylus pen can be provided at low cost.

Based on the above findings, the present inventors have intensively studied the impedance of a stylus pen. As a result, while the impedance of the conventional stylus pen is 8.2 × 10 ³ Ω to 5.5 × 10 ⁶ Ω, even a stylus pen having an impedance within a predetermined range higher than this is used. The inventors have found that the touch panel reacts, and have come up with the present invention.

  Accordingly, an object of the present invention is to provide a stylus pen used for a touch panel, which can operate the touch panel while being a stylus pen having a higher impedance than before.

In order to solve the above-described problems, a stylus pen according to the present invention is a stylus pen used in a capacitive touch panel, and is formed of a shaft tube and a conductive material provided at a tip portion of the shaft tube. At least a core portion, and the impedance between the pen tip of the core portion and the specific position of the shaft cylinder exceeds 5.5 × 10 ⁶ Ω and 1.6 × 10 ⁸ Ω or less at a measurement frequency of 1 KHz. It is characterized by being. Note that the specific position of the shaft cylinder means any position between the front end portion and the rear end portion (including the front end portion and the rear end portion) of the shaft cylinder.

The impedance of the conventional stylus pen (impedance between the pen tip of the core and the rear end of the shaft cylinder) is 8.2 × 10 ³ Ω to 5.5 × 10 ⁶ Ω. Such a stylus pen is configured such that the impedance between the nib of the core portion and a specific position of the shaft tube exceeds 5.5 × 10 ⁶ Ω and is 1.6 × 10 ⁸ Ω or less.

In this way, the touch panel can be operated even with a stylus pen having a higher impedance than a conventional stylus pen. As a result, the content of the conductive material in the synthetic resin material forming the shaft tube can be reduced, or the shaft tube can be formed without any inclusion, and the outer surface of the shaft tube of the stylus pen can be made of metal, etc. It is not necessary to provide the conductive layer, and the manufacturing cost can be reduced.
That is, when the impedance between the nib of the core and the specific position of the shaft tube is 5.5 × 10 ⁶ Ω or less, it is necessary to use a shaft tube containing a large amount of conductive material, or It is necessary to use a shaft cylinder provided with a conductive layer such as a metal on the surface, which has the disadvantage of increasing manufacturing costs. On the other hand, when the impedance between the nib of the core part and the specific position of the shaft cylinder exceeds 1.6 × 10 ⁸ Ω, there is an adverse effect that the touch panel does not react.

Here, the impedance of the stylus pen is inherently a problem with the impedance between the nib of the core and the grip part where the user grips the stylus pen, but the position where the shaft tube is gripped differs depending on the user. It is desirable that the impedance between the nib of the core part and the rear end part of the shaft cylinder is more than 5.5 × 10 ⁶ Ω and not more than 1.6 × 10 ⁸ Ω.
Thus, when the impedance between the nib of the core part and the rear end of the shaft cylinder is more than 5.5 × 10 ⁶ Ω and not more than 1.6 × 10 ⁸ Ω, any part of the shaft tube The touch panel can be operated even if it is held and operated.

  Moreover, it is desirable that the shaft cylinder is formed of a synthetic resin material that does not contain a conductive material. Thus, since the shaft tube is formed of a synthetic resin material that does not contain a conductive material, the manufacturing cost can be reduced.

Furthermore, it is desirable that an inner space is formed in the shaft cylinder, an impedance adjusting member made of a conductive material is accommodated in the inner space, and the impedance is adjusted by adjusting an accommodation amount of the impedance adjusting member. .
A stylus pen having a desired impedance can be obtained by changing the accommodation amount of the conductive material in the internal space.
In addition, it is desirable that the impedance adjusting member and the core portion are integrally formed.

  ADVANTAGE OF THE INVENTION According to this invention, it is a stylus pen used for a touch panel, Comprising: Although it is a stylus pen which has impedance higher than before, the stylus pen which enables operation of a touch panel can be obtained.

FIG. 1 is a cross-sectional view showing an embodiment of the stylus pen of the present invention. FIG. 2 is a cross-sectional view showing a modification of the stylus pen of the present invention. FIG. 3 is a cross-sectional view showing another modification of the stylus pen of the present invention. FIG. 4 is a cross-sectional view showing a state in which the core portion is formed up to the central portion of the shaft tube in the modification shown in FIG. 3. FIG. 5 is a cross-sectional view showing a state in which the core portion is formed up to the tip end portion of the shaft cylinder in the modification shown in FIG. 3. FIG. 6 is a side view showing the state of impedance measurement, (a) is a diagram showing the state of impedance measurement between the tip of the core and the tip of the shaft tube, and (b) is the core of the core. The figure which shows the measurement state of the impedance between a front-end | tip part and the center part of a shaft cylinder, (c) is a figure which shows the measurement state of the impedance between the front-end | tip part of a core part, and the rear-end part of a shaft cylinder. FIG. 7 is an exploded view schematically showing a configuration of a conventional touch panel. FIG. 8 is a plan view schematically showing sensor electrodes of the touch panel of FIG.

An embodiment of a stylus pen according to the present invention will be described with reference to FIGS.
As shown in FIG. 1, the stylus pen 1 includes a shaft tube 2, a core portion 3 fitted and attached to a recess 2 a at a tip portion of the shaft tube 2, and a rear end portion of the shaft tube 2. The tail plug 4 is attached.
The tip portion (pen nib) of the core portion 3 and the shaft cylinder 2 are electrically connected by fitting the core portion 3 into the recess 2 a of the shaft tube 2.
In addition, although the space part 2b is formed in the shaft cylinder 2 of the stylus pen 1, no member is accommodated in the space part 2b.

The shaft cylinder 2 can be formed into a predetermined shape and a predetermined dimension by various materials such as a synthetic resin containing a conductive material, a synthetic resin not containing a conductive material, or a metal material.
Specific examples of the shaft tube made of a synthetic resin containing a conductive material include a shaft tube made of a synthetic resin containing carbon black, metal fine particles, carbon nanotubes, or the like, or a shaft tube made of a conductive resin. The shaft cylinder made of a metal material is specifically a shaft cylinder made of metal such as aluminum, or a shaft cylinder in which metal plating is applied to the surface of a synthetic resin shaft cylinder.
However, a shaft tube made of a synthetic resin containing a conductive material and a shaft tube made of a metal material are expensive, so that polypropylene (PP) or polycarbonate generally used for a shaft tube of a writing instrument or the like is used. A shaft cylinder made of a synthetic resin not containing a conductive material such as (PC) or acrylonitrile / butadiene / styrene (ABS) is preferable.

The core 3 is made of a conductive material. For example, it can be made into a predetermined shape and a predetermined dimension by various materials such as a fiber bundle of conductive resin, conductive rubber, and the like.
As the conductive resin fiber, for example, a fiber based on polyester resin, polyamide resin, or the like is coated with a conductive material, directly kneaded into the fiber, or chemically bonded to the fiber. What gave electroconductivity is used. In this case, all the fibers constituting the fiber bundle may be conductive fibers, or some may be conductive fibers.

Further, as the conductive material, in addition to metal materials such as carbon black, copper sulfide, and inorganic materials such as carbon nanotubes, conductive materials such as polypyrrole, polythiophene, polyethylenedioxythiophene, polyisothianaphthene, and polyaniline are used as organic materials. Resin.
When using these conductive resins, 2,3,7,8-tetracyano-1,4,6,9-tetraazanaphthalene, dodecylbenzenesulfonic acid, p-toluenesulfone are used in order to adjust the conductivity appropriately. A conductive resin to which a dopant such as an acid is added can be used.
In addition, you may form a core part with the said conductive resin, without coat | covering the fiber which uses a polyester resin, a polyamide resin, etc. as a base material.

  In addition, as the conductive rubber, it is possible to use various rubber raw materials such as natural rubber and synthetic rubber blended with conductive carbon black, metal powder, or carbon nanotube.

By the way, in the stylus pen according to the present invention, the impedance between the tip portion (pen tip) of the core portion 3 and the specific position of the shaft cylinder 2 is 5.5 × 10 ⁶ Ω at a measurement frequency of 1 KHz. And 1.6 × 10 ⁸ Ω or less. The specific position of the shaft cylinder 2 means any position between the front end portion and the rear end portion of the shaft cylinder 2 (including the front end portion and the rear end portion).

Here, when the impedance between the pen point of the core part and the specific position of the shaft cylinder is less than 5.5 × 10 ⁶ Ω at the measurement frequency of 1 KHz, the core part is the same as in the conventional stylus pen. It is necessary to use a material with good conductivity for 3 and use a shaft tube 2 containing a large amount of a conductive material or a shaft tube 2 provided with a conductive layer such as metal on the outer peripheral surface. There is an adverse effect that the manufacturing cost increases.
On the other hand, when the impedance between the nib of the core part and the specific position of the shaft cylinder exceeds 1.6 × 10 ⁸ Ω, there is a problem that the touch panel does not react.

In addition, the impedance of the stylus pen is inherently problematic from the pen tip of the core part to the grip part gripped by the user, but the position at which the shaft tube is gripped differs depending on the user.
Therefore, the impedance between the pen tip of the core part 3 and the rear end part of the shaft tube 2 exceeds 5.5 × 10 ⁶ Ω and becomes 1.6 × 10 ⁸ Ω or less, so that the user can The touch panel can be operated even when any part of the cylinder 2 is gripped, which is preferable.

In addition, even when the impedance between the pen tip of the core part 3 and the tip part (specific position) of the shaft tube 2 exceeds 5.5 × 10 ⁶ Ω and is 1.6 × 10 ⁸ Ω or less, The user can operate the touch panel by gripping at least the tip portion of the shaft tube 2.
However, in general, the gripping part that grips the stylus pen is more distal than 1/2 of the total length of the shaft tube, so that the pen tip of the core portion and at least 1/2 of the total length of the shaft tube It is desirable that the impedance between them exceeds 5.5 × 10 ⁶ Ω and is 1.6 × 10 ⁸ Ω or less.

  Next, a stylus pen in which an impedance adjusting member is accommodated in the space 2b inside the shaft cylinder 2 of the stylus pen 1 will be described with reference to FIG. In FIG. 2, the same or corresponding members as those shown in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 2, in the stylus pen 10, the conductive member 5 is accommodated in the space 2 b of the shaft tube 2. As the impedance adjusting member 5, it is possible to use conductive fibers, conductive resin, conductive rubber, conductive sponge in which thread-like metal materials are combined, a graphite sintered body, or the like used for the core portion 3 described above. it can.

In this case, in order to electrically connect the core portion 3 and the impedance adjusting member 5, a core 6 formed of a conductive resin is provided. The core 6 includes a disk-like flange-like base portion 6a and terminal portions 6b and 6c formed on the upper and lower surfaces of the flange-like base portion 6a. The terminal portion 6 b is connected to the core portion 3, and the terminal portion 6 c is connected to the impedance adjusting member 5.
Therefore, the fiber bundle core 3 is electrically connected from the tip (pen nib) to the shaft cylinder 2 through the center core 6 and the impedance adjusting member 5.

Thus, by accommodating the impedance adjusting member 5 made of a conductive member in the space portion 2b of the shaft tube 2, the impedance from the tip portion (pen tip) of the core portion 3 to the grip portion of the shaft tube 2 can be reduced. It can be adjusted easily. That is, the impedance can be adjusted by adjusting the accommodation amount of the impedance adjusting member in the space 2b.
In FIG. 2, the impedance adjusting member 5 is accommodated up to the rear end portion of the shaft cylinder 2.

Even in the stylus pen 10, the impedance between the tip portion (pen tip) of the core portion 3 and a specific position of the shaft tube 2 exceeds 5.5 × 10 ⁶ Ω at a measurement frequency of 1 KHz. .6 × 10 ⁸ Ω or less.
Here, as described above, because the position where the shaft tube is gripped differs depending on the user, the impedance between the pen tip of the core portion 3 and the rear end portion of the shaft tube 2 exceeds 5.5 × 10 ⁶ Ω. 1.6 × 10 ⁸ Ω or less is preferable because the touch panel can be operated even if the user holds any part of the shaft tube 2.

Even when the impedance between the nib of the core part 3 and the tip part (specific position) of the shaft cylinder 2 exceeds 5.5 × 10 ⁶ Ω and becomes 1.6 × 10 ⁸ Ω or less, the user The touch panel can be operated by gripping at least the tip end portion of the shaft tube 2.
However, in general, the gripping part that grips the stylus pen is more distal than 1/2 of the total length of the shaft tube, so that the pen tip of the core portion and at least 1/2 of the total length of the shaft tube It is desirable that the impedance between them exceeds 5.5 × 10 ⁶ Ω and is 1.6 × 10 ⁸ Ω or less.

Next, modified examples of the stylus pen provided with the impedance adjusting member will be described with reference to FIGS. 3, 4, and 5. 3 to 5, members that are the same as or correspond to the members shown in FIG. 1 are given the same reference numerals, and detailed description thereof is omitted.
As shown in FIGS. 3, 4, and 5, the stylus pen 20 is characterized in that a core portion and an impedance adjustment member are integrated.

The tip portion (pen nib) of the core portion 21 and the shaft tube 2 are electrically connected by the core portion 21 being inserted through the through hole 2c of the shaft tube 2 and being fixed.
As the material of the core portion 21, various materials such as the same material as the core portion 3, a conductive resin fiber bundle, and conductive rubber can be used.
Since the core portion 21 has a function of an impedance adjusting member, the core portion 21 extends in the shaft cylinder 2 (the core portion and the impedance adjusting member are integrated). For this reason, since the core portion 21 is long and heavy, it is preferable to use a lighter conductive fiber or conductive resin. As a result, a stylus pen that is lightweight and easy to handle can be obtained.

Even in the stylus pen 20, the impedance between the tip portion (pen tip) of the core portion 21 and a specific position of the shaft cylinder 2 exceeds 5.5 × 10 ⁶ Ω and is not more than 1.6 × 10 ⁸ Ω. Made.
In addition, as described above, since the position where the shaft tube is gripped differs depending on the user, the impedance between the pen tip of the core portion 21 and the rear end portion of the shaft tube 2 exceeds 5.5 × 10 ⁶ Ω. It is preferable that the touch panel is operated to 1.6 × 10 ⁸ Ω or less because the touch panel can be operated even if the user grips any part of the shaft tube 2.

It is also used when the impedance between the nib of the core 21 and the tip (specific position) of the shaft tube 2 exceeds 5.5 × 10 ⁶ Ω and is 1.6 × 10 ⁸ Ω or less. A person can operate the touch panel by gripping at least the distal end portion of the shaft tube 2.
However, in general, the gripping part that grips the stylus pen is on the tip side of half of the total length, so that the impedance between the pen tip of the core part and at least 1/2 of the total length of the shaft tube. However, it is desirable that it is more than 5.5 × 10 ⁶ Ω and not more than 1.6 × 10 ⁸ Ω.

  Moreover, as shown in FIG. 3, the core part 21 is extended (accommodated) to the rear end part of the shaft tube 2, but if the impedance is adjusted as necessary, for example, as shown in FIG. Alternatively, it may be extended (accommodated) to the distal end portion of the shaft tube 1 or to the middle portion of the shaft tube 1 as shown in FIG.

The present invention will be further described based on examples.
Various stylus pens with different impedances were prepared. As a form of the stylus pen, the form shown in FIG. 3, FIG. 4 and FIG. 5 is used. It is a synthetic resin made of polypropylene (PP) generally used in a shaft tube of a writing instrument or the like, and contains a conductive material. A cylindrical shaft cylinder having an outer diameter of 10 mm, a wall thickness of 1 mm, and a length of 120 mm was formed.

The core is made of conductive fiber with a volume resistivity catalog value of 10 ⁶ to 10 ⁸ Ω · cm manufactured by KB Seiren Co., Ltd., a product name: Beltron, and a core material with a volume resistivity of 10 ⁸ Ω · cm is used. Obtained.
Then, the diameter of the core portion is 6 mm, and three types of core portions having a length of 118.5 mm (Example 1), 70 mm (Example 2), and 20 mm (Example 3) are formed. Attached to. The core was mounted so as to protrude 5 mm from the tip of the shaft tube.
Then, as shown in FIG. 6, one electrode is attached to the tip (pen nib) of the core part, and an electrode having a width of 25 mm is 20.5 mm from the tip of the shaft tube as shown in FIG. At the tip, as shown in FIG. 6 (b), it is attached to the center of 57.5mm from the tip of the shaft tube, and as shown in FIG. 6 (c), it is attached to the rear end of 90.5mm from the tip of the shaft tube. Impedance was measured at a measurement frequency of 1 kHz using an LCR meter (Agilent U1733).
The measurement results are shown in Table 1.

尚、表１中の「−」は、測定限界の２×１０^８Ωを超え、インピーダンスを測定することができないことを表わしている。

“-” In Table 1 indicates that the measurement limit of 2 × 10 ⁸ Ω is exceeded and impedance cannot be measured.

Further, a fiber having a polyester resin as a base material was impregnated with a conductive resin (polythiophene) having a catalog value of 10 ⁵ to 10 ⁶ Ω · cm, and then dried to have a volume resistivity of 10 ⁶ Ω · cm. A core material was obtained.
Then, the diameter of the core portion is 6 mm, three types of core portions having a length of 118.5 mm (Example 4), 70 mm (Example 5), and 20 mm (Example 6) are formed. Attached to. The core was mounted so as to protrude 5 mm from the tip of the shaft tube.
Then, as shown in FIG. 6, one electrode is attached to the tip (pen nib) of the core part, and an electrode having a width of 25 mm is 20.5 mm from the tip of the shaft tube as shown in FIG. At the tip, as shown in FIG. 6 (b), it is attached to the center of 57.5mm from the tip of the shaft tube, and as shown in FIG. Impedance was measured at a measurement frequency of 1 kHz using an LCR meter (Agilent U1733).
Table 2 shows the measurement results.

尚、表２中の「−」は、測定限界の２×１０^８Ωを超え、インピーダンスを測定することができないことを表わしている。

In Table 2, “−” indicates that the measurement limit of 2 × 10 ⁸ Ω is exceeded and impedance cannot be measured.

In addition, a film in which a resistance film (transparent conductive thin film) having a surface resistivity of 10 ⁵ Ω / sq is formed on a PET film as shown in the previous application (Japanese Patent Application No. 2013-081766) is prepared as a touch panel. The film was stuck on the cover glass which is the dielectric material of the said touch panel using the 4th generation ipod touch by Apple company.
In this example, since durability was not considered, only a transparent conductive thin film was formed without forming a protective layer.
This transparent conductive thin film is a conductive PEDOT-PSS aqueous solution composed of a mixture of conductive polymer PEDOT (poly (3,4-ethylenedioxythiophene)) and polyanion PSS (polystyrene sulfonate). A polymer low conductivity grade was uniformly deposited on a PET film.

And the said front-end | tip part of the stylus pen of Examples 1-6, the center part, and the rear-end part were hold | gripped, and the reaction of the touch panel was verified using the 4th generation ipod (trademark) made from Apple.
As a result, it was confirmed that the touch panel reacted in each part when the front end part, the center part, and the rear end part of Example 1 were gripped.
In Example 2, it was confirmed that the touch panel reacted at the tip and the center. Here, the touch panel reacted at the center of the impedance of 1.6 × 10 ⁸ , but the touch panel did not react at the rear end of the impedance exceeding the measurement limit of 2 × 10 ⁸ Ω.
Furthermore, in Example 3, it was confirmed that the touch panel reacted at the tip. Here, although the touch panel reacted at the front end portion with an impedance of 1.6 × 10 ⁸ , the touch panel did not react at the center portion and the rear end portion of the impedance exceeding the measurement limit of 2 × 10 ⁸ Ω.

When the front end part, the center part, and the rear end part of Example 4 were gripped, it was confirmed that the touch panel reacted in each part.
Moreover, in Example 5, it confirmed that a touch panel reacted in the front-end | tip part and the center part. Here, the touch panel reacted at the center of the impedance of 7.8 × 10 ⁷ , but the touch panel did not react at the rear end of the impedance exceeding the measurement limit of 2 × 10 ⁸ Ω.
Furthermore, in Example 6, it was confirmed that the touch panel reacted at the tip. Here, although the touch panel reacted at the front end portion with an impedance of 1.5 × 10 ⁸ , the touch panel did not react at the center portion and the rear end portion of the impedance exceeding the measurement limit of 2 × 10 ⁸ Ω.

From the above example, it was confirmed that the touch panel would react if the impedance between the nib of the core and the specific position of the shaft tube was 1.6 × 10 ⁸ Ω or less at a measurement frequency of 1 KHz. .

In addition, although the said Example showed the case where the film in which the transparent conductive thin film which has a surface resistivity of 10 ^5.0 ohms / sq was formed on the surface of the cover glass for touch panels was shown, the cover glass for touch panels In the case where a film on which a transparent conductive thin film having a surface resistivity of 10 ^7.0 Ω / sq is pasted is attached to the surface, the impedance between the nib of the core and the specific position of the shaft tube is It was confirmed that the touch panel reacted when the measurement frequency exceeded 5.5 × 10 ⁶ Ω and 1.6 × 10 ⁸ Ω or less at 1 KHz.
Moreover, in the said embodiment and the Example, although control (adjustment) of impedance was performed by adjusting the accommodation amount (length) of the impedance adjustment member which consists of an electroconductive member, this invention corresponds to this. It is not limited, for example, by controlling the volume resistivity of the impedance adjustment member (or the core and the impedance adjustment member are integrally formed), or, alternatively, the wall thickness of the shaft tube, the shaft The impedance may be controlled (adjusted) by controlling the diameter of the space portion of the cylinder.

1, 10, 20 Stylus pen 2 Shaft cylinder 2a Recess 2b Space (internal space)
2c Through-hole 3 Core part 4 Tail plug 5 Impedance adjustment member 6 Middle core 21 Core part (core part having function of impedance adjustment part)

Claims (5)

A stylus pen used in a capacitive touch panel,
A shaft cylinder and at least a core formed of a conductive material provided at the tip of the shaft cylinder,
The impedance between the pen point of the core part and the specific position of the shaft cylinder is more than 5.5 × 10 ⁶ Ω and 1.6 × 10 ⁸ Ω or less at a measurement frequency of 1 KHz. Stylus pen. The specific position is a rear end portion of the shaft cylinder,
The impedance between the pen tip of the core part and the rear end of the shaft cylinder is more than 5.5 × 10 ⁶ Ω and not more than 1.6 × 10 ⁸ Ω. Stylus pen.   The stylus pen according to claim 1, wherein the shaft cylinder is formed of a synthetic resin material that does not contain a conductive material. An internal space is formed in the shaft tube,
The impedance adjustment member made of a conductive material is accommodated in the internal space, and the impedance is adjusted by adjusting the accommodation amount of the impedance adjustment member. The stylus pen described in 1.   The stylus pen according to claim 4, wherein the impedance adjusting member and the core portion are integrally formed.

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