Pen input device sheet with elastic layer having recessed protruding pattern facing a position detecting device
Provided is a pen input device sheet disposed over a position detection region of a position detecting sensor, the pen input device sheet including an elastic material layer that is composed of a plurality of layer portions stacked in a thickness direction and has elasticity, an opposite side of a side of the position detecting sensor in the elastic material layer being employed as a side of a writing input surface to which writing input with an electronic pen is made, and the pen input device sheet being configured such that a vibration frequency characteristic of a kinetic friction coefficient when the electronic pen is moved at a predetermined speed on the writing input surface of the pen input device sheet matches a vibration frequency characteristic of a kinetic friction coefficient when a predetermined writing material is moved at the predetermined speed on a predetermined writing medium.
1 . A pen input device sheet for a position detection region of a position detecting sensor, the pen input device sheet comprising:
an elastic material layer that has elasticity and is composed of a plurality of layer portions stacked in a thickness direction of the pen input device sheet,
wherein, in operation, a side opposite of a side of the position detecting sensor in the elastic material layer is a writing input surface to which writing input with an electronic pen is made,
wherein the pen input device sheet is configured such that a vibration frequency characteristic of a kinetic friction coefficient when the electronic pen is moved at a predetermined speed on the writing input surface of the pen input device sheet matches the vibration frequency characteristic of the kinetic friction coefficient when a predetermined writing material is moved at the predetermined speed on a predetermined writing medium,
wherein the pen input device sheet is configured such that a frequency that exhibits a peak magnitude of vibration of the kinetic friction coefficient defined by regarding, as a maximum value, an apex of a waveform of frequency distribution of magnitudes of the vibration in the vibration frequency characteristic of the kinetic friction coefficient when the electronic pen is moved at the predetermined speed on the writing input surface of the pen input device sheet in a state in which a predetermined writing pressure is applied is in a predetermined frequency range,
wherein a hardness of a tip part of the predetermined writing material that comes into contact with the predetermined writing medium is one of a plurality of predetermined hardnesses, and
wherein the frequency that exhibits the peak magnitude of the vibration of the kinetic friction coefficient is set according to the hardness of the tip part of the predetermined writing material.
2 . The pen input device sheet according to claim 1 , wherein
the pen input device sheet is configured such that a frequency that exhibits a peak magnitude of vibration of the kinetic friction coefficient prominent from a waveform of frequency distribution of magnitudes of the vibration in the vibration frequency characteristic of the kinetic friction coefficient when the electronic pen is moved at the predetermined speed on the writing input surface of the pen input device sheet in a state in which a predetermined writing pressure is applied is in a predetermined frequency range.
3 . The pen input device sheet according to claim 1 , wherein
the pen input device sheet is configured such that a frequency that exhibits a peak magnitude of vibration of the kinetic friction coefficient in the vibration frequency characteristic of the kinetic friction coefficient when the electronic pen is moved at the predetermined speed on the writing input surface of the pen input device sheet in a state in which a predetermined writing pressure is applied corresponds to a frequency that exhibits a peak magnitude of vibration of the kinetic friction coefficient in the vibration frequency characteristic of the kinetic friction coefficient when the predetermined writing material is moved at the predetermined speed on the predetermined writing medium in a state in which the predetermined writing pressure is applied.
4 . The pen input device sheet according to claim 1 , wherein
the predetermined writing material is a pencil, and the predetermined writing medium is paper.
5 . The pen input device sheet according to claim 1 , wherein
the predetermined writing material is a ballpoint pen, and the predetermined writing medium is paper.
6 . The pen input device sheet according to claim 1 , wherein
a material having elasticity in the elastic material layer is polyvinyl chloride resin.
7 . The pen input device sheet according to claim 1 , wherein
the layer portions of the elastic material layer have configurations different from each other.
8 . The pen input device sheet according to claim 7 , wherein
the layer portions of the elastic material layer are different from each other in density per unit volume.
9 . The pen input device sheet according to claim 7 , wherein
the layer portions of the elastic material layer are different from each other in hardness per unit volume.
10 . The pen input device sheet according to claim 1 , wherein
a base layer is disposed on a surface on a side of the elastic material layer between the position detecting sensor and the elastic material layer.
11 . The pen input device sheet according to claim 10 , wherein
an adhesive layer is disposed on a surface on a side of the base layer between the position detecting sensor and the base layer.
12 . The pen input device sheet according to claim 1 , wherein
an adhesive layer is disposed on a surface on a side of the elastic material layer between the position detecting sensor and the elastic material layer.