Background

Sleep Apnea

Sleep apnea occurs when an individual stops breathing for stretches of time while he/she is sleeping. This can put a person at risk for heart disease and in extreme cases death. For a more comprehensive understanding please visit http://www.sleep-apnea-guide.com/sleep-apnea-oxygen-level.html .

Pulse Oximetry and Photoplethysmography

Pulse oximetry utilizes photoplethysmography, which is a cheap way to detect a user's blood oxygen levels, SpO2,, as well as their heart beat from the skin's surface. Photoplethysmography is noninvasive and for this project will utilize an LED light and photodiode to measure the amount of light absorbed by the skin. For an in depth look into photoplethysmography please visit https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3394104/ .

Nasal Thermistor

A nasal thermistor measures the change in temperature of a user's breathing to determine how many times he/she has inhaled and exhaled. From this information a respiration rate can be determined and displayed on an LCD screen for the user to see. For more information please go to https://www.ncbi.nlm.nih.gov/pubmed/9493929