Capacitive three-dimensional sensor

A capacitive three-dimensional sensor, which is configured to sense inputs in plane X and Y directions and a depth Z direction, the capacitive three-dimensional sensor comprising:

• a light-guide unit having a side surface and an operation surface, the side surface being formed along the depth Z direction and including a light entering portion, through which light from a light source enters, the operation surface being configured to input the inputs and including a light output portion, from which the light exits;
• a sheet-like X-Y electrode body configured to sense the inputs in the plane X and Y directions;
• an easily deformable body including a sheet-like elastic body;
• and
• a sheet-like Z electrode body configured to sense the input in the depth Z direction,
• the light-guide unit, the sheet-like X-Y electrode body, the easily deformable body, and the sheet-like Z electrode body being arranged in the stated order to overlap one another when viewed in the depth Z direction,
• the light-guide unit including a decorative sheet, which is provided optionally, and a light-guide sheet configured to guide the light that has entered the light-guide unit from the side surface and output the light toward the light output portion,
• the decorative sheet and the light-guide sheet being arranged in the stated order to overlap each other when viewed in the depth Z direction,
• the light-guide sheet having a bending stiffness D1 calculated by the following equation (1) and the decorative sheet having a bending stiffness D2 calculated by the following equation (2), D1 and D2 totaling less than 256:
• D1=(E1)×(h1)3÷[12×{1−(ν1)2}] Equation (1)
• D2=(E2)×(h2)3÷[12×{1−(ν2)2}] Equation (2)
• where D1, E1, h1, and ν1 represent the bending stiffness (unit:
• N⋅mm), a bending modulus (unit:
• N/mm2), a thickness (unit:
• mm), and a Poisson ratio of the light-guide sheet, respectively, and D2, E2, h2, and ν2 represent the bending stiffness (unit:
• N⋅mm), a bending modulus (unit:
• N/mm2), a thickness (unit:
• mm), and a Poisson ratio of the decorative sheet, respectively.