Vaisala HUMICAP® Celebrates Its 40 Years

In 1973, Vaisala introduced HUMICAP®, the world's first thin-film capacitive humidity sensor. Since then, Vaisala has become the market leader in relative humidity measurements, and thin-film capacitive humidity sensors have developed from one company's innovation into a global industry standard. Constantly under further research & development, the Vaisala HUMICAP sensor is still the most accurate and reliable humidity sensor on the market.

As the world's first thin-film capacitive humidity sensor, the HUMICAP was a radical innovation that completely changed the way humidity is measured. Until then, reliable humidity measurement was an unresolved challenge and hair hygrometers were commonly used. The new ground-breaking technology had no moving parts, and it was amazingly small due to the advanced use of thin-film technologies. 

The innovation was originally designed for a new radiosonde; however the greatest interest for this revolutionary new sensor came from various industrial customers. In fact, it marked the beginning of Vaisala's industrial business. Continuous innovation of the sensor has developed INTERCAP, an interchangeable humidity sensor, as well as HUMICAP variants which measure moisture in oil. The fourth generation humidity sensor with improved stability and chemical tolerance was introduced in 2006. The sensor is manufactured in-house from start to finish in state-of-the-art cleanroom facilities at Vaisala.

Today, products based on Vaisala HUMICAP technology range from radiosondes to hand-held meters to industrial transmitters. The sensor covers applications from HVAC to the most demanding industrial and environmental applications, both indoors and out. The sensor continues to offer superior performance in the most demanding environments. As the HUMICAP celebrates 40 years, it also celebrates its first year onboard NASA's Mars Rover Curiosity.