Resistiivsed

Resistiivsed describes devices or sensors whose output is based on changes in electrical resistance caused by external stimuli. They are used across electronics, instrumentation, and sensing applications. The principle relies on Ohm's law: the resistance of a material or a configuration changes when a stimulus—such as pressure, temperature, light, or mechanical strain—modifies its geometry or conductivity. The electrical signal is typically obtained by creating a voltage divider or by measuring a bridge circuit to determine the change in resistance.

Common types include resistive touchscreens, which consist of two thin, conductive layers separated by a spacer. When the screen is pressed, the layers touch at the point of contact, completing a circuit and allowing position coordinates to be calculated. Resistive touchscreens can be 4-wire, 5-wire, or 8-wire, and they work with any pointing device, including gloves or styluses, but they tend to have lower optical clarity and require periodic calibration.

Other resistive sensors include thermistors (temperature-dependent resistance), photoresistors (light-dependent resistance), and force-sensing resistors (FSRs) that change resistance with applied pressure. Strain gauges create resistance changes when deformed and are used to measure stress or displacement.

Materials commonly used include carbon-based thick films, metal-oxide films, and conductive polymers. Advantages of resistive devices include simple electronics, low cost, and robustness in harsh or dirty environments, as well as compatibility with standard instrumentation. Disadvantages include lower sensitivity and slower response for some sensors, higher power consumption in active configurations, and reduced durability for touchscreen applications compared with capacitive alternatives.