A gas sensor with improved sensitivity. The gas sensor comprises an active sensor unit, a reference sensor unit and a temperature control circuit. The active sensor unit has an active detector. The reference sensor unit has a reference detector. The temperature control circuit is provided and configured to keep a detector at a predetermined temperature.

The present invention provides a catalytic conversion-type sensor that detects a detection target gas by detecting a conversion gas produced through a reaction, the catalytic conversion-type sensor including: a gas flow path that allows the detection target gas to flow down; and a conversion portion that is connected to the gas flow path, the conversion portion including, on a side partitioned by a diffusion means that allows the detection target gas to naturally diffuse, a heated catalyst portion that produces a conversion gas by causing the detection target gas to come into contact with a heated catalyst and react with the heated catalyst, and a sensor element portion that is capable of detecting the conversion gas produced through the reaction.

The present invention provides a catalytic conversion-type sensor that detects a detection target gas by detecting a conversion gas produced through a reaction, the catalytic conversion-type sensor including: a gas flow path that allows the detection target gas to flow down; and a conversion portion that is connected to the gas flow path, the conversion portion including, on a side partitioned by a diffusion means that allows the detection target gas to naturally diffuse, a heated catalyst portion that produces a conversion gas by causing the detection target gas to come into contact with a heated catalyst and react with the heated catalyst, and a sensor element portion that is capable of detecting the conversion gas produced through the reaction.

A system includes a primary combustible gas sensor and a trigger combustible gas sensor including a first trigger element of low-thermal-mass which includes a first trigger heating element in operative connection with electronic circuitry. The trigger combustible gas sensor also includes a second trigger element of low thermal mass including a second trigger heating element. The second trigger element is also in operative connection with the electronic circuitry. The electronic circuitry further has a first trigger mode of operating in which the first trigger element is heated to a temperature at or above a temperature at which the first trigger element causes combustion of the at least one combustible gas analyte and wherein the second trigger element is operated as a trigger compensating element. The electronic circuitry is configured to operate the trigger combustible gas sensor to detect a value of a response at or above a threshold value. The primary combustible gas sensor is activated from a low-power state upon the threshold value being detected by the trigger combustible gas sensor.

A system includes a primary combustible gas sensor and a trigger combustible gas sensor including a first trigger element of low-thermal-mass which includes a first trigger heating element in operative connection with electronic circuitry. The trigger combustible gas sensor also includes a second trigger element of low thermal mass including a second trigger heating element. The second trigger element is also in operative connection with the electronic circuitry. The electronic circuitry further has a first trigger mode of operating in which the first trigger element is heated to a temperature at or above a temperature at which the first trigger element causes combustion of the at least one combustible gas analyte and wherein the second trigger element is operated as a trigger compensating element. The electronic circuitry is configured to operate the trigger combustible gas sensor to detect a value of a response at or above a threshold value. The primary combustible gas sensor is activated from a low-power state upon the threshold value being detected by the trigger combustible gas sensor.

A method for sensing gas by a gas sensing device, the method may include generating, by a semiconductor temperature sensing element that is spaced apart from a gas reactive element and is thermally coupled to the gas reactive element, detection signals that are indicative of a temperature of the gas reactive element; wherein the gas reactive element and the semiconductor temperature sensing element are of microscopic scale; and processing, by a readout circuit of the gas sensing device, the detection signals to provide information about a gas that affected the temperature of the gas reactive element.

A method for sensing gas by a gas sensing device, the method may include generating, by a semiconductor temperature sensing element that is spaced apart from a gas reactive element and is thermally coupled to the gas reactive element, detection signals that are indicative of a temperature of the gas reactive element; wherein the gas reactive element and the semiconductor temperature sensing element are of microscopic scale; and processing, by a readout circuit of the gas sensing device, the detection signals to provide information about a gas that affected the temperature of the gas reactive element.

A gas sensing device that includes a (a) gas reactive element that has a gas dependent temperature parameter; and (b) a semiconductor temperature sensing element that is spaced apart from the gas reactive element and is configured to sense radiation emitted from the gas reactive element and generate detection signals that are responsive to a temperature of the gas reactive element; wherein the gas reactive element and the semiconductor temperature sensing element are of microscopic scale.

A gas sensing device that includes a (a) gas reactive element that has a gas dependent temperature parameter; and (b) a semiconductor temperature sensing element that is spaced apart from the gas reactive element and is configured to sense radiation emitted from the gas reactive element and generate detection signals that are responsive to a temperature of the gas reactive element; wherein the gas reactive element and the semiconductor temperature sensing element are of microscopic scale.

Provided are a gas detection method and a gas detector which have a high durability to silicone poisoning and is capable of detecting the type and the concentration of a target gas to be detected with certain accuracy even when the detector is used in an environment where a silicone compound exists. The gas detector employs a contact combustion-type gas sensor which includes two gas detection elements, each intermittently driven, and in which only one gas detection element is supplied with a gas through a silicone removal filter. Acquired in an energization duration of each of the gas detection elements are two or more pieces of output data by the one gas detection element and two or more pieces of output data by the other gas detection element, which constitutes output variation patterns for a test gas. The output variation patterns are contrasted to a reference output variation pattern of each of four largely divided types of reference gases of a paraffinic hydrocarbon gas, a solvent gas, a hydrogen gas, and an argon gas, with the reference output variation patterns being acquired in advance, thereby identifying the type of the target gas being detected in the test gas.