Vaisala Oyj

Jukka Leppänen

Lars Stormbom

Matti Lyyra

Petteri Survo

Veli-Pekka Viitanen

Marko Jalonen

Kaisa Lehmus

Arto Harju

Eero Hiltunen

Risto Heikkinen

According to an example aspect of the present invention, there is provided a sensor structure formed on a substrate comprising a sensor frame, comprising electric contacts for sensors, an active sensor within the sensor frame comprising at least a capacitive humidity sensor. In accordance with the invention the active sensor is connected to the sensor frame only by a thin thermally isolating layer supporting the active sensor, the thermally isolating layer including electric contacts from the sensor frame.

Fast humidity sensor and a method for calibrating the fast humidity sensor

According to an example aspect of the present invention, there is provided a method in connection with a radiosonde, the method comprising measuring a humidity of the atmosphere at several different altitudes in the atmosphere, measuring a pressure at several different altitudes in the atmosphere or calculating the pressure from an altitude of the radiosonde obtained from GPS or other satellite navigation system, measuring or estimating a temperature of a humidity sensor, and measuring a relative humidity by a capacitor with a polymer insulator, wherein the relative humidity value is corrected based on a correction factor, which is a function of pressure, humidity sensor temperature, and relative humidity, such that the humidity value decreases when pressure decreases.

Method in connection with a radiosonde and system

The invention relates to a sensor structure and a method. The sensor structure includes a first sensor having a sensing element sensitive to humidity of the environment. In accordance with the invention the sensor structure also includes s second sensor having a sensing element sensitive to humidity, the second sensor comprising a catalytic permeable layer positioned on the second sensor such that it is between the sensing element of the second sensor and the environment.

Dual gas sensor structure and measurement method

A method for measuring the temperature dependency of a sensor element for a variable, the value of which varies with the temperature, for any liquid. The method includes the steps of changing the temperature of the liquid over time, simultaneously collecting the data produced by the sensor element, and thereafter using the data produced by the sensor element at the different temperatures to determine coefficients for compensation algorithms of the temperature dependencies of the sensor element, thus producing a correlation between the change in temperature and the other measured variables.

Method and device for compensating temperature dependencies

The invention relates to a method and apparatus for measurement of total water content in a liquid. According to the method, the relative water content (aw) of the liquid is measured in a first measurement step at a first temperature (T). According to the invention, the temperature of the liquid under measurement is altered from the first temperature (T) and the relative water content is measured in a second measurement step at the second, altered temperature (T), whereby, based on these at least two measurement values (aw()T, aw()T), the total water content is determined from the temperature dependence of water dissolution into the liquid under measurement.

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Luhtajoki, Finland

Jukka Leppänen