Operation state detecting apparatus, operation state detecting sheet, and electronic instrument

An operation state detecting apparatus comprising:

• an electronic device which includes an operation surface and which can detect whether there is contact by operation in a plurality of positions on the operation surface;
• and
• a sheet material which can be attached to and detached from the operation surface of the electronic device,
• wherein,
• the sheet material includes a plurality of projecting portions, each of the projecting portions deforms to change a contact state on the operation surface according to strength of external force applied to each of the projecting portions in a state with the sheet material attached to the operation surface, and
• a processor of the electronic device sets a plurality of detecting regions on the operation surface such that the contact states of each of the detecting regions are respectively changed by deforming of each of the projecting portions in a state with the sheet material attached to the operation surface, and detects whether there is contact with one of the projecting portions to which external force is applied at each of a plurality of positions in one of the detecting regions corresponding to the one of the projecting portions on the operation surface, and the processor performs a specific process according to strength or speed of an operation applied to the one of the projecting portions judged based on a detected result indicating a number of the contact positions or a size of area including the contact positions in the one of the detecting regions.