Non invasive gas analysis

摘要

A sensing device is provided. The device comprises a gas permeable member, a sensing member and optical means. The gas permeable member is arranged to receive gas from a substance to be tested. The sensing member is located adjacent to the gas permeable member and comprises a sensing substance. A property of the sensing substance is modified when it is brought into contact with the gas received by the gas permeable member. The optical means comprises a light source which is arranged to irradiate the sensing substance together with a first sensor which is configured to detect a change in the aforementioned property of the sensing substance.