Apple’s highly anticipated new flagship iPhone 18 Pro is the first model to shrink the Dynamic Island design and hide the Face ID hardware under the screen. However, initial reviews and tests show that this technological innovation has brought with it an unexpected accessory incompatibility. When matte or frosted screen protectors are applied to the device, the infrared scanning system stops working.

How Does Under-Screen Face ID Technology Work?

Apple is clearly shrinking the large, pill-shaped Dynamic Island that has been used for a long time in the iPhone 18 Pro and Pro Max models. While a single circular hole is left for the front camera, the infrared (IR) sensors that power the Face ID system are moved under the OLED panel in the upper left region of the screen.

To implement this system, the pixel density in the relevant part of the screen is consciously reduced. This transparent area with low pixel density allows infrared light to pass through the glass and map the user’s face. This enables biometric authentication without a physical sensor notch on the screen.

Why Do Matte and Ghost Screen Protectors Cause Problems?

A detailed review shared by popular technology publisher Dave Lee (Dave2D) reveals that the system in question is quite sensitive to screen protector selection. The rough or micro-textured surface of matte (anti-glare) and opaque ghost glass protectors causes infrared light beams to refract and scatter.

Due to this optical distortion, the underlying sensor cannot accurately read the face map, and the Face ID unlock process fails completely.

In transparent and smooth tempered glass protectors, since no random breakage occurs, infrared light reaches the sensor without any problems and the system works without loss.

Which Screen Protector Should Users Choose?

Similar to the protector incompatibility issues experienced with optical under-display fingerprint readers on the Android side, this situation is appearing so clearly for the first time in the Apple ecosystem. iPhone 18 Pro and iPhone 18 Pro Max owners should choose completely transparent (clear) tempered glass models instead of matte, frosted, or privacy filter protectors in order not to compromise biometric security.