Abstract: Embodiments relate generally to systems and methods for detecting particulate matter in the air. A particulate matter sensor may comprise an airflow channel; a light source configured to pass light through the airflow channel; an airflow generator configured to generate airflow into the airflow channel; a waveguide configured to direct light from the light source after it passes through the airflow channel and scatters off of particulate matter within the airflow channel; a photodiode configured to receive light scattered by the waveguide; and a computing device coupled to the photodiode having a processor and a memory storing instructions which, when executed by the processor, determines a mass concentration of particles in the airflow channel based on an output of the photodiode.

Abstract: Embodiments relate to systems and methods for providing airflow within a particulate matter sensor. A particulate matter sensor may comprise an air duct, a light source configured to pass light through the air duct, a extender connected to the light source configured to dissipate thermal energy generated by the light source, and to generate a updraft of airflow into the air duct, a photodetector located in the air duct, and a computing device coupled to the photodetector. The computing device has a processor and a memory storing instructions which, when executed by the processor, determines a mass concentration of particles in the air duct based on an output of the photodetector.

Abstract: Embodiments relate generally to systems and methods for detecting particulate matter in the air. A particulate matter sensor may comprise an airflow channel; a light source configured to pass light through the airflow channel; an airflow generator configured to generate airflow into the airflow channel; a waveguide configured to direct light from the light source after it passes through the airflow channel and scatters off of particulate matter within the airflow channel; a photodiode configured to receive light scattered by the waveguide; and a computing device coupled to the photodiode having a processor and a memory storing instructions which, when executed by the processor, determines a mass concentration of particles in the airflow channel based on an output of the photodiode.

Abstract: A particulate matter (PM) sensor. The sensor comprises a mass separation fluid tunnel body defining a fluid inflow channel, a first fluid channel branch opening off of the inflow channel and having a first outlet, a second fluid channel branch opening off of the inflow channel and having a second outlet, and a fluid port between the first fluid channel branch and the second fluid channel branch, a fan located downstream of the first outlet and the second outlet, a photodetector located in the first fluid channel branch, and a computing device coupled to the photodetector having a processor and a memory storing instructions which, when executed by the processor, determines a mass concentration of particles in the first fluid channel branch based on an output of the photodetector.

Abstract: Embodiments relate generally to methods and systems for balancing the internal pressure of a gas detector. A method for venting internal pressure changes of a gas detector may comprise providing an inlet to a sensor located within a housing of the gas detector; isolating the sensor from the rest of the interior of the housing; providing at least one vent between the interior of the housing and the external environment, wherein the sensor is isolated from airflow into and out of the vent; and preventing one or more elements from entering the interior of the housing through the at least one vent via a breathable membrane aligned with the at least one vent.

Abstract: Embodiments relate generally to systems and methods for dissipating electric charge within a particulate matter sensor, and reducing the effects of electromagnetic interference within the particulate matter sensor. A particulate matter sensor may comprise an airflow channel; a light source configured to pass light through the airflow channel; a photodetector configured to receive light from the light source after it passes through the airflow channel; a printed circuit board coupled to the photodetector having a processor and a memory storing instructions which, when executed by the processor, determines an indication of a mass concentration of particles in the airflow channel based on an output of the photodetector; and a shield cover configured to attach to and cover at least a portion of the printed circuit board, and configured to reduce the effects of electromagnetic interference within the particulate matter sensor.

Abstract: Embodiments relate generally to systems and methods for detecting particulate matter in the air. A particulate matter sensor may comprise an airflow channel; a light source configured to pass light through the airflow channel; an airflow generator configured to generate airflow into the airflow channel; a waveguide configured to direct light from the light source after it passes through the airflow channel and scatters off of particulate matter within the airflow channel; a photodiode configured to receive light scattered by the waveguide; and a computing device coupled to the photodiode having a processor and a memory storing instructions which, when executed by the processor, determines a mass concentration of particles in the airflow channel based on an output of the photodiode.

Abstract: Embodiments relate to systems and methods for providing airflow within a particulate matter sensor. A particulate matter sensor may comprise an air duct, a light source configured to pass light through the air duct, a extender connected to the light source configured to dissipate thermal energy generated by the light source, and to generate a updraft of airflow into the air duct, a photodetector located in the air duct, and a computing device coupled to the photodetector. The computing device has a processor and a memory storing instructions which, when executed by the processor, determines a mass concentration of particles in the air duct based on an output of the photodetector.

Abstract: A particulate matter (PM) sensor. The sensor comprises a mass separation fluid tunnel body defining a fluid inflow channel, a first fluid channel branch opening off of the inflow channel and having a first outlet, a second fluid channel branch opening off of the inflow channel and having a second outlet, and a fluid port between the first fluid channel branch and the second fluid channel branch, a fan located downstream of the first outlet and the second outlet, a photodetector located in the first fluid channel branch, and a computing device coupled to the photodetector having a processor and a memory storing instructions which, when executed by the processor, determines a mass concentration of particles in the first fluid channel branch based on an output of the photodetector.