A switch unit includes: a tactile switch; a cable which transmits an operation signal generated when the tactile switch is operated; a formed part where a fitting engagement portion which is disposed on an operation section exterior member at a predetermined position, a recessed surface which is formed on a side of a first end portion with respect to the fitting engagement portion and where the tactile switch is mounted, a cable fixing portion which is disposed on a side of a second end portion which is a side opposite to the first end portion with the fitting engagement portion positioned between the first end portion and the second end portion and to which the cable is connected, and a circuit which electrically connects the recessed surface and the cable fixing portion to each other and transmits an operation signal generated by the tactile switch to the cable are formed.

A membrane switch device includes first and second membrane layers, a spacing layer between the membrane layers, and a flexible printed circuit board. The first membrane layer includes a first surface and first conductive wires on the first surface and extending to a first wire area to form first contact pads. The second membrane layer includes a second surface and second conductive wires on the second surface and extending to a second wire area to form second contact pads. A wire-connecting end of the flexible printed circuit board is between the first membrane layer and the second membrane layer. A first protection layer of the flexible printed circuit board and the first contact pads are not overlapped with each other, and a second protection layer of the flexible printed circuit board and the second contact pads are not overlapped with each other.

A membrane switch device includes first and second membrane layers, a spacing layer between the membrane layers, and a flexible printed circuit board. The first membrane layer includes a first surface and first conductive wires on the first surface and extending to a first wire area to form first contact pads. The second membrane layer includes a second surface and second conductive wires on the second surface and extending to a second wire area to form second contact pads. A wire-connecting end of the flexible printed circuit board is between the first membrane layer and the second membrane layer. A first protection layer of the flexible printed circuit board and the first contact pads are not overlapped with each other, and a second protection layer of the flexible printed circuit board and the second contact pads are not overlapped with each other.

A membrane switch device includes first and second membrane layers, a spacing layer between the membrane layers, and a flexible printed circuit board. The first membrane layer includes a first surface and first conductive wires on the first surface and extending to a first wire area to form first contact pads. The second membrane layer includes a second surface and second conductive wires on the second surface and extending to a second wire area to form second contact pads. A wire-connecting end of the flexible printed circuit board is between the first membrane layer and the second membrane layer. A first protection layer of the flexible printed circuit board and the first contact pads are not overlapped with each other, and a second protection layer of the flexible printed circuit board and the second contact pads are not overlapped with each other.

A membrane switch device includes first and second membrane layers, a spacing layer between the membrane layers, and a flexible printed circuit board. The first membrane layer includes a first surface and first conductive wires on the first surface and extending to a first wire area to form first contact pads. The second membrane layer includes a second surface and second conductive wires on the second surface and extending to a second wire area to form second contact pads. A wire-connecting end of the flexible printed circuit board is between the first membrane layer and the second membrane layer. A first protection layer of the flexible printed circuit board and the first contact pads are not overlapped with each other, and a second protection layer of the flexible printed circuit board and the second contact pads are not overlapped with each other.

Electrodes Ex and regions of top plate opposed to electrodes Ex constitute switches SWx that have capacitances varying when the regions of top plate are depressed from top plate toward electrodes Ex. Depression detection circuit calculates the capacitance change amounts of switches SWx indicating changes of the capacitances from a reference value. Depression detection circuit calculates the maximum value and sum of the capacitance change amounts of switches SWx. When the capacitance change amount of at least one switch SWx exceeds threshold TH_EDGE and a situation in which the ratio of the maximum value to the sum is equal to or greater than threshold COMP_LEVELx has lasted for the number of repetitions in SW_DET_COUNT, depression detection circuit determines that the switch having the maximum value of the capacitance change amount is in a depressed state.

A keyboard includes a backlight module, a base plate, a membrane circuit disposed on the base plate, and a plurality of key structures disposed on the membrane circuit. The backlight module includes a light source, a reflective layer, a light guide layer, and a shielding layer. The light source is disposed corresponding to the light guide layer. The light guide layer is located between the shielding layer and the reflective layer. The light guide layer has a through-hole. The shielding layer and the reflective layer are in contact with each other in the through-hole of the light guide layer. The base plate is disposed on the shielding layer. The base plate has a positioning portion disposed corresponding to the through-hole of the light guide layer, which protrudes toward the reflective layer or the membrane circuit.

A keyboard includes a backlight module, a base plate, a membrane circuit disposed on the base plate, and a plurality of key structures disposed on the membrane circuit. The backlight module includes a light source, a reflective layer, a light guide layer, and a shielding layer. The light source is disposed corresponding to the light guide layer. The light guide layer is located between the shielding layer and the reflective layer. The light guide layer has a through-hole. The shielding layer and the reflective layer are in contact with each other in the through-hole of the light guide layer. The base plate is disposed on the shielding layer. The base plate has a positioning portion disposed corresponding to the through-hole of the light guide layer, which protrudes toward the reflective layer or the membrane circuit.

A button structure and a terminal using the same are provided. The button structure includes a connecting element, a press element, and at least one elastic element connected to the connecting element and the press element. The elastic element is configured to provide a restoring force after the press element is pressed toward the connecting element. The connecting element is provided with an instruction transmission port and at least one of a current transmission port and a data transmission port. The press element is provided with an instruction triggering port and at least one of a current transmission pin and a data transmission pin. The current transmission pin is electrically connected to the current transmission port to output or input current. The data transmission pin is electrically connected to the data transmission port to output or input data.

A button structure and a terminal using the same are provided. The button structure includes a connecting element, a press element, and at least one elastic element connected to the connecting element and the press element. The elastic element is configured to provide a restoring force after the press element is pressed toward the connecting element. The connecting element is provided with an instruction transmission port and at least one of a current transmission port and a data transmission port. The press element is provided with an instruction triggering port and at least one of a current transmission pin and a data transmission pin. The current transmission pin is electrically connected to the current transmission port to output or input current. The data transmission pin is electrically connected to the data transmission port to output or input data.