Patent ID: 9201002
Filing Date: 2015-12-01
Classification: A61B,G01N

Abstract:
1. A gas measurement module configured to be inserted into a respiratory circuit that is in fluid communication with an airway of a subject, the gas measurement module comprising: a chamber having a first opening and a second opening, wherein the chamber is configured to form a flow path between the first opening and the second opening such that if the gas measurement module is inserted into the respiratory circuit, gas from the airway of the subject is transported through the flow path; an infrared source configured to emit infrared electromagnetic radiation along an optical path that passes through the flow path formed by the chamber; a movable filter member including a first filter element configured to filter electromagnetic radiation in a first wavelength band and a second filter element configured to filter electromagnetic radiation in a second wavelength band; a photosensitive detector held at a fixed position along the optical path to receive infrared electromagnetic radiation that has been filtered by the filter member and has passed through the flow path formed by the chamber, and to generate output signals that convey information related to one or more parameters of the received infrared electromagnetic radiation; and an actuator configured to actuate the filter member between a first position and a second position, wherein at the first position the first filter element is positioned in the optical path, and wherein at the second position the second filter element is positioned in the optical path, wherein one or more of (i) the electromagnetic energy is blocked from becoming incident on the filter member as filter member is being actuated between the first position and the second position, via a gate positioned between (i)(a) the infrared source and the first opening and (i)(b) the second opening and the filter member to selectively block the optical path, (ii) the output signal of the photosensitive detector is disconnected from a processor in response to the filter member being actuated between the first position and the second position, via a switch that selectively couples the output signal of the photosensitive detector to the processor, and (iii) the infrared source is controlled to emit the electromagnetic radiation in pulses that are coordinated with the filter member being positioned at a position corresponding to a filter element, via one or more controllers that control one or more of the infrared source and the actuator.