US 11,986,284 B2
Capnometer
Julian Carter, Cambridge (GB); Jeremy Walsh, Cambridge (GB); Russell Overend, Glasgow (GB); Craig Whitehill, Glasgow (GB); and Colin Phimister, Glasgow (GB)
Assigned to CAMBRIDGE RESPIRATORY INNOVATIONS LTD, Cambridge (GB)
Appl. No. 16/981,244
Filed by CAMBRIDGE RESPIRATORY INNOVATIONS LTD, Cambridge (GB)
PCT Filed Mar. 13, 2019, PCT No. PCT/IB2019/052040
§ 371(c)(1), (2) Date Sep. 15, 2020,
PCT Pub. No. WO2019/175800, PCT Pub. Date Sep. 19, 2019.
Claims priority of application No. 1804172 (GB), filed on Mar. 15, 2018.
Prior Publication US 2021/0038118 A1, Feb. 11, 2021
Int. Cl. A61B 5/083 (2006.01); A61B 5/08 (2006.01); G01N 21/3504 (2014.01); G01N 33/497 (2006.01)
CPC A61B 5/0836 (2013.01) [A61B 5/082 (2013.01); G01N 21/3504 (2013.01); G01N 33/497 (2013.01); G01N 2201/0634 (2013.01); G01N 2201/0636 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A capnometer for detecting a concentration of a component in a gas, wherein the gas is inhaled and/or exhaled by a patient, the capnometer comprising:
an air flow region through which the gas passes to and/or from the patient's lung;
a mid-IR semiconductor emitter configured to provide IR light at a wavelength in the range 3-5 μm;
a mid-IR semiconductor detector to detect the IR light and a reflector to reflect the IR light emitted by the emitter;
wherein the emitter, the detector and the reflector are arranged such that the IR light emitted by the emitter passes through the air flow region via the reflector to the detector, wherein the capnometer further comprises:
a breath tube that defines a channel between the emitter, the detector and the reflector, the channel defining the air flow region, the emitter and the detector being mounted adjacently on a circuit board on one side of the breath tube and the reflector being provided on an opposing side of the breath tube,
wherein the reflector has a planar geometry,
wherein the reflector is selected from the group consisting of a Fresnel reflector and a reflective diffractive optical element, and
wherein the emitter and the detector are aligned such that light from the emitter is focused by the reflector onto the detector.