Samsung SM-G960W User Manual page 225

Settings
Hold your device about 25-35 cm away from your face with the screen facing towards you.
Registering irises
The device can save the iris data of one person only. You cannot register more than
one set of irises.
1
On the Settings screen, tap Lock screen and security → Iris Scanner.
2
Unlock the screen using the preset screen lock method.
If you have not set a screen lock method, create one.
3
Read the on-screen instructions and tap CONTINUE.
To register only one iris of your eyes, tap Register just one iris.
4
Hold the device with the screen facing towards you and look at the screen.
25-35 cm
25-35 cm
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