Are Under-Display Ultrasonic Fingerprint Sensors Safe from Hearing Damage?

As the use of under-display ultrasonic fingerprint sensors becomes increasingly popular, one question that often arises is whether these sensors can cause hearing damage. Understandably, concerns about human safety are paramount. Let's explore the claims surrounding these sensors and set the record straight.

Understanding Ultrasonic Technology

Under-display ultrasonic fingerprint sensors work by emitting ultrasonic frequencies to detect and verify fingerprints. These frequencies are beyond the range of human hearing, typically between 40 kHz and 100 kHz. They are designed to be safe and efficient in both their physical and auditory impact on users.

How Safe Are Ultrasonic Frequencies for Humans?

The primary concern with ultrasonic frequencies is whether they can cause hearing damage. However, for this to be a real issue, the frequency needs to be at a level that can damage human hearing. The typical threshold for hearing damage is around 70 decibels (dB). Even ultrasonic frequencies, which humans cannot hear, don't have enough energy to cause any significant auditory impact.

The ultrasonic frequencies used in fingerprint sensors typically operate at a much lower power level, usually around 10 dB to 20 dB. This is well below the threshold that would cause any form of hearing damage. Furthermore, the frequencies are only active when a finger is placed on the sensor, and the device has a built-in safety mechanism to ensure the sensor does not trigger until it detects contact with a finger.

Addressing Common Misconceptions

Some people might believe that the ultrasonic frequencies used in these sensors can cause hearing damage because they are powerful enough to disturb the sensitive cochlea. However, this is a misconception. The key factor in causing hearing damage is the amplitude and duration of sound exposure, not just the frequency.

For example, prolonged exposure to loud music through earbuds at volumes above 50 dB can be far more harmful to the ears than the ultrasonic frequencies used in fingerprint sensors. This is why you should always keep the volume of your audio devices at a safe level and avoid prolonged exposure to high-decibel sounds.

The idea that ultrasonic frequencies alone are dangerous is not supported by scientific evidence. The frequency of a sound does not inherently make it harmful; what matters is the actual level of energy and the duration of exposure.

Potential Risks and Precautions

While ultrasonic fingerprint sensors are generally safe, manufacturers still implement various safety measures to ensure user safety. For instance, the sensors have built-in delay mechanisms to ensure they activate only when a finger is placed on the sensor. Additionally, these sensors are designed to use minimal energy, further reducing any potential risk.

It's worth noting that if there were any risk of hearing damage from ultrasonic fingerprint sensors, it would be highly irresponsible for manufacturers to release such products. The potential for lawsuits and reputational damage would be significant. Therefore, manufacturers thoroughly test and validate their products to ensure they are safe for consumers.

Conclusion

In summary, under-display ultrasonic fingerprint sensors are safe from causing hearing damage. The frequencies they use are not within the range of human hearing and do not have the decibel level to cause any permanent hearing loss. The common misconception about the potential for hearing damage is based on a misunderstanding of how sound works and the typical threshold for causing auditory damage.

By choosing products that have been rigorously tested and designed with safety in mind, you can continue to enjoy the convenience and security that under-display ultrasonic fingerprint sensors offer with peace of mind.