A pulse oximeter measures heart rate by detecting changes in light absorption as blood pulses through your finger.
Here's a breakdown of how it works:
- Light Emission: A pulse oximeter emits two wavelengths of light through your fingertip.
- Light Absorption: This light is absorbed differently by oxygenated and deoxygenated hemoglobin in your blood.
- Pulsatile Flow: Because blood flow is pulsatile (it comes in waves with each heartbeat), the amount of light absorbed changes with each pulse.
- Detection & Calculation: The pulse oximeter measures these changes in light absorption. It is this pattern of changes that allows it to determine your pulse rate as it detects the number of times the blood flow is 'pulsed' past the detector.
Here's a simple table summarizing the process:
| Step | Description |
|---|---|
| Light Emission | Two wavelengths of light are sent through your finger. |
| Absorption | Oxygenated and deoxygenated hemoglobin absorb light differently, changes with blood flow. |
| Detection | The device measures the amount of light that passes through. |
| Calculation | The device detects the pulsating nature of the blood flow to determine heart rate by counting the pulses per minute. |
Key Insights:
- The pulse oximeter does not directly "listen" to your heart. It infers heart rate based on the light absorption changes associated with blood flow.
- The accuracy of heart rate measurement is based on its ability to detect the small fluctuations in light absorption caused by each heartbeat.
- This is a non-invasive and painless way to track both heart rate and oxygen saturation.
The pulse oximeter utilizes changes in light absorption during blood flow to calculate heart rate. According to our reference, these devices send two wavelengths of light through your finger to measure your pulse rate and the oxygen saturation in the blood.
