Tactile sensor and apparatus including tactile sensor

A tactile sensor comprising:

• a light emission unit configured to emit light;
• a light guide unit, extending in a predetermined direction, provided to guide light, incident from the light emission unit via an optical end optically coupled with the light emission unit, in the predetermined direction, the light guide unit including a pair of surfaces, opposite to each other, extending in the predetermined direction;
• an optical translucent elastic member optically coupled with the light guide unit via one surface of the pair of surfaces and including at least one marker configured to diffuse light, incident via the one surface, toward the light guide unit;
• a light-receiving unit provided on a side of the light guide unit closer to the other surface of the pair of surfaces than to the one surface, and including a plurality of light-receiving elements on a light-receiving surface;
• and
• a plurality of opening portions provided between the other surface and the light-receiving unit, and optically opened such that light from the at least one marker is projected to different positions, spaced apart from one another, on the light-receiving surface of the light-receiving unit,
• wherein the light-receiving unit is configured to receive at least two signals from the at least one marker,
• wherein the light-receiving unit outputs first information regarding a distribution of the light including the two signals received on the light-receiving surface, and
• wherein the light-receiving unit outputs the first information to a calculation unit, the calculation unit being configured to calculate second information regarding an external force received by the optical translucent elastic member based on the first information.