DIY Pulse Oximeter using Arduino

A pulse oximeter measures blood oxygen saturation (SpO2) - a critical vital sign. After COVID-19, pulse oximeters became household items. Building your own teaches biomedical signal processing and optical sensor techniques.

Why This Project Is Popular

Biomedical electronics is an exciting field with growing demand. This project demonstrates understanding of optical sensors (LED + photodiode), signal processing, and calibration. It's an excellent project for students interested in medical devices.

Project Ideas or Guide

Build a working pulse oximeter:

• Optical Sensor: Use MAX30100/MAX30102 which has red and IR LEDs plus photodiode.
• SpO2 Calculation: Measure ratio of IR to red light absorption to calculate oxygen saturation.
• Signal Processing: Filter noise, find peaks, calculate R-value for SpO2.
• Display: Show SpO2 percentage and BPM on OLED display.
• Alert: Buzzer when SpO2 drops below safe level (94%).

Components Used

• Arduino Nano
• MAX30100/MAX30102 Sensor
• OLED Display
• Buzzer
• Finger Clip

FAQ

Q: Is DIY pulse oximeter accurate?

A: Within ±2% of commercial devices when properly calibrated.

Q: How does SpO2 measurement work?

A: Oxygenated hemoglobin absorbs more IR light, deoxygenated absorbs more red. Ratio indicates SpO2.