BOPLA expands the input device program with capacitive membrane keypads! These keyboards are resistant to acids, dirt and other contaminants and withstand high mechanical stress. Surface cleaning is easy and the highest hygiene standards are maintained.
Detailed Product Description
There is no mechanical connection with the operator, no mechanical keys. The operating element is separated from the user by a smooth surface (for example, glass, plastic or a non-conductive surface of another kind), which makes it possible to simplify surface cleaning and use the device in areas with increased vandalism and in hygienically clean areas (for example, in medicine and in the food industry). The smooth surface allows you to control the device without pressure, i.e. just a light touch. The absence of a tactile effect can be replaced by an optical or acoustic signal. Keyboards and switches operating on a capacitive principle can be implemented either as individual keys or as a combination of keys – any form of keys is possible. There are no restrictions for customization!
Technical implementation
The touch surface of the key consists of two zones isolated from each other (transmitting and receiving electrodes). Oscillations are generated from the transmitter side, which are transferred to the receiving electrode via capacitive coupling. When pressed with a finger, the capacity of the human body is connected to the receiver. Transmitted signals are damped. Through damping, “switching pulses” are detected and evaluated. Digital filters and specially adapted algorithms ensure error-free operation, regardless of short-term interference and slow changes (rain, plaque or effusion, etc.).
Various design options
Full The capacitive control unit consists of three elements: capacitive sensors, electronics for processing results and control surfaces (usually glass or plexiglass). Often, the sensors and the electronics for processing the results are located on the same printed circuit board. If you want to realize the illumination of the surface of the keys, or if the surface has a curved or uneven shape, then the printed circuit board cannot be mounted directly behind the disk; in these cases, it is recommended to use a separate sensor film. The touch surface is applied to the polyester film by screen printing and connected to the electronics using a ribbon cable. On a printed circuit board, at a certain distance from; the front board, there are LEDs that provide planar illumination of the keys.