A transmitter device incorporating a strain gauge proportional push button is disclosed. The transmitter device includes a printed circuit board including one or more electrical components thereon and a proportional push button having a flexible membrane, a dome switch positioned beneath the flexible membrane and attached to the printed circuit board, the dome switch being proximate to the flexible membrane such that depression of the flexible membrane causes the dome switch to snap down and thereby form a closed circuit in the dome switch, and a strain gauge formed on or applied to the printed circuit board and positioned adjacent the dome switch, the strain gauge generating an electrical output proportional to an amount of deflection of the printed circuit board caused by pressure exerted thereon by depression of the flexible membrane and the dome switch.

A key structure is provided. The key structure comprises a substrate, a membrane circuit disposed on the substrate, a conduction switch disposed on the membrane circuit, a keycap, a bending portion fixed to the keycap, an elastic member disposed on the membrane circuit and abutting against the keycap, and a connecting rod disposed movably between the membrane circuit and the keycap. The connecting rod includes an operating arm and an engaging portion. The operating arm is connected to the engaging portion, and the engaging portion selectively engages with the bending portion. When the operating arm moves in a direction parallel to a surface of the keycap, the operating arm drives the engaging portion to disengage from the bending portion and the elastic member provides a force against the keycap to move the keycap away from the conduction switch.

A keyboard device is disclosed, which includes an upper housing, a conductive membrane, a key top including a bottom surface and an actuator disposed on the bottom surface, a lower housing and a soft elastic element located on the conductive membrane, wherein the actuator penetrates the upper housing, and the soft elastic element has an engaging part to engage with the key top such that the key top is prevented from being separated from the soft elastic element when the key top rebounds.

A low profile keyboard backlight module includes an electrically insulative bottom membrane layer, an intermediate membrane layer including a conducting layer, an insulative layer and a light-emitting layer attached together through lamination and bonded to the top surface of the bottom membrane layer, and an electrically insulative top membrane layer bonded to a top surface of the intermediate membrane layer opposite to the bottom membrane layer and having an integrated elastic layer located at a top surface thereof to support a set of keys. Thus, the low profile keyboard backlight module provides optimal waterproof effects and is practical for use in an electronic product having light, thin, short and small characteristics.