Which type of temperature sensor is known to provide the highest accuracy?

RTDs, or Resistance Temperature Detectors, are recognized for their high accuracy in temperature measurement. This accuracy stems from their design, which utilizes the predictable change in electrical resistance of metals with temperature changes. Typically, RTDs are constructed from pure materials, such as platinum, which ensure stable and repeatable responses to temperature fluctuations.

They often have a linear response over a wide temperature range, making them very reliable for critical applications in industrial and laboratory settings where precise temperature control is essential. The typical accuracy of RTDs can reach within ±0.1°C, depending on the calibration and specifications of the sensor.

Thermocouples, while popular for a variety of applications due to their wide temperature range and durability, tend to have less accuracy than RTDs, especially at lower temperatures. Thermistors can also provide high accuracy but are generally limited to a narrower temperature range and may have nonlinear outputs. Filled bulb thermometers, while useful for certain applications, typically do not match the accuracy levels available with RTDs and also respond more slowly. Therefore, RTDs are often the preferred choice when the highest accuracy is required in temperature sensing.