Systems And Methods For Determining Physiological Information With A Computing Device

A method of detecting oxygen levels in blood using a computing device and an add-on device, comprising:

• calculating a first mean value of light intensity detected by a first partition of an image sensor on the computing device at a first time for a red wavelength to generate a red PPG signal;
• calculating a second mean value of light intensity detected by a second partition of the image sensor on the computing device at the first time for an infrared wavelength to generate an infrared PPG signal;
• filtering the red PPG signal and the infrared PPG signal to allow frequencies ranging from 0.5 Hz to 4 Hz to pass;
• calculating an absorptivity ratio from the red PPG signal and the infrared PPG signal;
• and
• calculating the oxygen levels based on the absorptivity ratio.

A physiological information detection device comprising:

• a body;
• a first light filter retained in the body and configured to filter light emitted by a light source;
• a first lens retained in the body proximate the first light filter, wherein the first lens is configured to direct the light exiting the first light filter out a first surface of the first lens;
• a second lens retained in the body and configured to receive into a second surface of the second lens the light exiting the first lens, wherein the first surface of the first lens and the second surface of the second lens are substantially coplanar;
• and
• a second light filter retained in the body proximate the second lens, wherein an image sensor is configured to detect the light exiting the second light filter.