Force sensor and method of making same

A laminated force sensor comprising:

• two backing sheets substantially overlying each other, each providing a pair of confronting surfaces;
• a substantially non-patterned conductive layer deposited on each of the confronting surfaces;
• a substantially non-patterned semiconductive layer deposited on at least one of the conductive layers;
• a pattern of non-conductive material interposed between the confronting surfaces of the backing sheets and contacting the semiconductive layer, the pattern defining at least one sensing area devoid of non-conductive material, said sensing area confronting said semiconductive layer;
• whereby electrical current will flow between the conductive layers only when a force component is exerted orthogonally to the backing sheets at a location corresponding to the sensing area devoid of non-conductive material.

A laminated force sensor comprising:

• two, thin, flexible backing sheets substantially overlying each other, each having a surface which confronts the surface of the other, each of said surfaces having a uniform, nonpatterned layer of conductive ink deposited thereon, and a uniform, non-patterned semiconductive layer deposited on at least one of the layers of conductive ink;
• and
• a pattern of non-conductive material interposed between the confronting surfaces of the backing sheets and confronting the semiconductive layer, the pattern defining at least one sensing area devoid of non-conductive material, said sensing area confronting said semiconductive layer;
• whereby when a force component is exerted orthogonally to the backing sheets at a location corresponding to the sensing area devoid of non-conductive material, current will flow between said conductive layers through said semiconductive layer and when a force component is applied orthogonally to the backing sheets at other locations, current will not flow between said conductive layers through said semiconductive layer.

A method of making a laminated force sensor comprising:

• providing first and second backing sheets having uniformly deposited conductive ink layers, each of the conductive ink layers being adapted to be electrically connected to a source of electric current and each of the backing sheets defining an outer perimeter surrounding the conductive ink layers;
• providing at least one of the conductive layers with a uniformly applied semiconductive material to form a semiconductive layer;
• and
• interposing non-conductive material in a selected pattern between the conductive layers and confronting the semiconductive layer, the pattern defining at least one sensing area devoid of non-conductive material;
• whereby electric current will flow through the semiconductive layer only when a force component is exerted orthogonally to the backing sheets at a location corresponding to the area devoid of non-conductive material.

A method of making a force sensor comprising:

• substantially covering a pair of insulative, flexible, polymeric surfaces with electrically conductive ink to form a pair of non-patterned conductive layers;
• substantially covering at least one of the conductive layers with a non-patterned semiconductive material layer;
• and
• securing the surfaces in an opposed relationship to each other with a patterned layer of non-conductive material which substantially covers the surfaces except for a preselected sensing area, thereby limiting conduction between the conductive layers to the preselected sensing area.