SMK Develops Capacitive Touch Switch Using Transparent Film

Mar 16, 2013
Mami Akasaka, Tech-On!
The newly-developed touch switch
The newly-developed touch switch
[ If it clicks, the expanded picture will open ]

SMK Corp developed a capacitive touch switch using a transparent film for home appliances and office equipment and started to accept orders.

The company formed transparent touch switches by printing organic conductive polymer on a PET (polyethylene terephthalate) film substrate. The thickness of the switch's sensor part is 75μm.

The new switch has a higher productivity than switches using transparent conductive films that require patterning such as ITO films, reducing production costs, SMK said. It also has a higher flexibility than ITO film-based switches.

The switch is equipped with a high-sensitivity detection chip. Therefore, even when a thick cover panel is attached to the switch, it is possible to smoothly operate the switch. An acrylic cover panel of up to 3mm thickness or a glass cover panel of up to 5mm thickness can be attached to the switch.

The switch can be operated with a finger. Its operating temperature ranges from -20 to +70°C. The maximum number of keys is 22.

The production capacity for the switch is 500,000 units per month (in the case of a 4-inch product). SMK will provide the switch either as a touch switch and a chip or as a touch switch and a substrate equipped with a chip.