Face ID is one of the features unique to iPhones. Face ID sensors can identify your face with extreme accuracy.
However, can Face ID unlock your iPhone in pitch dark without any external light sources?
Does iPhone Face ID work in the dark?
iPhone Face ID works even in total darkness. Face ID uses an IR dot projector and an IR camera. It doesn’t require external light sources for your iPhone’s Face ID to work.
iPhone Face ID has two major components: the IR dot projector and the IR camera. The IR dot projector projects an IR dot pattern to your face. Then the IR camera scans the pattern to identify your facial features.
IR light is invisible to the human eye. That’s why you don’t see the IR dot pattern that is projected onto your face when you use iPhone Face ID.
However, the IR camera on the Face ID system can see the projected IR dot pattern and identify your face.
The IR camera doesn’t require any visible light in order to detect the projected dot pattern. Therefore, iPhone Face ID can identify your face even in pitch dark.
Does Face ID have poor accuracy in the dark?
Your iPhone’s Face ID has the same accuracy in the dark as in lighted conditions.
As we have said before, iPhone Face ID doesn’t rely on visible light. It has an IR dot projector to project an IR pattern to your face and the IR camera can read the IR dot pattern regardless of whether you have enough visible light or not.
Therefore, the accuracy of the iPhone Face ID won’t change depending on the amount of visible light.
However, Face ID requires you to hold the iPhone in portrait orientation. Holding the phone in different orientations at night can make it less accurate. For example, your iPhone may not unlock using Face ID when you are lying on your bed.
Is it okay to set up Face ID in total darkness?
It is not recommended to set up your iPhone’s Face ID in pitch dark.
iPhone Face ID may use your photo for additional data points. Therefore, setting up Face ID in the dark will only use the IR depth map, reducing the accuracy of the Face ID system. So it is better to set up Face ID in natural light for the best accuracy.
Why your iPhone’s Face ID doesn’t work in the dark?
iPhone Face ID should work properly even in pitch dark. So, if your iPhone’s face ID is not working in the dark, you may be holding the iPhone in an incorrect orientation.
iPhone expects you to hold the phone at the portrait orientation to unlock the phone using Face ID.
You can also try Face ID at different distances from your face. Usually, Face ID works best at arm’s length.
Does Android face unlock work in the dark?
Unlike iPhone Face ID, the face unlock feature on Android phones does not work in the dark.
Most Android phones use only the front camera for the face unlock feature. They don’t have an IR dot projector or an IR camera like that with iPhone Face ID.
However, some Android phones can automatically increase the screen brightness to illuminate your face in the dark. Then the face unlock will detect your face even without any external light sources.
Some rare Android phones also come with IR Face ID sensors. Such Android phones can identify your face even in total darkness. One such Android phone is Xiaomi Mi 8.
Conclusion
iPhone Face ID works even in the pitch dark. Face ID uses an IR dot projector and an IR camera to identify your facial features. Therefore, Face ID doesn’t require any external light sources to work properly.
On the other hand, face unlock on most Android phones rely on the front camera. They don’t have any IR dot projectors or IR cameras. As a result, Android face unlock only works with enough visible light.
