Apple Patent Infrared Fingerprint Scanner?

Yes, Apple has filed and been granted multiple patents for an infrared fingerprint scanner that could work through an iPhone or iPad display. The technology uses short-wave infrared (SWIR) light to read the unique patterns of a finger placed on or near the screen, potentially replacing the current Face ID or Touch ID systems. Here is what the patents describe, how the technology works, and what it could mean for future devices.

Background: Why Apple Is Exploring Under-Display Fingerprints

Apple switched from Touch ID to Face ID with the iPhone X in 2017, but it has continued to file patents for fingerprint sensing. The main reason is that many users prefer the convenience of a fingerprint sensor, especially when wearing a mask or when the phone is lying flat on a table. Under-display fingerprint sensors already exist on many Android phones, but they use optical or ultrasonic technology. Apple’s patents describe a different approach: infrared light that can pass through the OLED display and capture a high-resolution fingerprint image without needing a dedicated sensor hole.

The patents (e.g., US 10,909,351 B2 and US 11,055,526 B2) were filed with the US Patent and Trademark Office and published between 2019 and 2021. They are assigned to Apple Inc. and describe a system where an infrared emitter and detector are placed behind the display. The display itself is transparent to infrared light, so the sensor can see the finger when it touches the glass.

How an Infrared Fingerprint Scanner Works

Traditional optical scanners use visible light to photograph the fingerprint ridges. Ultrasonic scanners use sound waves to map the finger’s surface. An infrared scanner uses light in the 850–1550 nm wavelength range, which is invisible to the human eye. Here is the basic process:

• The phone emits a pulse of infrared light from an emitter behind the display.
• The light travels through the display layers and reflects off the finger.
• Fingerprint ridges and valleys reflect the light differently because of their varying distance from the glass.
• A sensor behind the display captures the reflected light and creates a high-contrast image of the fingerprint pattern.
• The phone’s processor compares that image to the stored fingerprint data to verify identity.

Because infrared light penetrates the display stack more easily than visible light, the sensor can be placed further from the surface, making it possible to have a full-screen sensing area rather than a small fixed spot.

What the Patent Claims Specifically

The key claims in Apple’s patents focus on the use of short-wave infrared (SWIR) for fingerprint imaging. One patent describes a system where the display emits light in the infrared range and a detector array captures the reflected light. Another patent details a method for reducing interference from the display’s own pixels, which can absorb or scatter infrared light.

The patents also mention using the same infrared sensor for other purposes, such as detecting the user’s pulse or blood oxygen level, because infrared light can penetrate the skin and reveal subsurface features. This could allow a single sensor to handle both biometric authentication and health monitoring.

It is important to note that a patent does not guarantee a product will be released. Apple files many patents that never make it to a shipping device. However, the continued filings suggest the company is seriously exploring this technology.

Infrared vs. Current Touch ID and Face ID

To understand what an infrared scanner would add, compare it with the current systems:

• Touch ID (capacitive): Uses a capacitive sensor that reads the electrical difference between ridges and valleys. It is fast and secure but requires a physical button or a dedicated sensor area.
• Face ID (structured light): Projects 30,000 invisible dots onto the face and reads the pattern with an infrared camera. It is secure but requires the user to look at the phone.
• Infrared fingerprint (patent): Would combine the convenience of Touch ID with the full-screen design of Face ID. It could work with wet or dry fingers better than capacitive sensors, and it could be placed anywhere on the display.

Apple’s existing Touch ID on the iPhone SE and older models is capacitive. The patent describes a system that could be used in a future iPhone, iPad, or even MacBook trackpad.

Challenges Apple Must Overcome

Several technical hurdles remain before such a sensor could ship:

• Display transparency: OLED panels are not fully transparent to infrared light. Apple’s patents suggest using a special pixel layout or adding a micro-perforation layer that is invisible to the eye but lets infrared through.
• Signal quality: The finger is about 1–2 mm above the sensor, and the display layers add distance. The infrared signal must be strong enough to produce a clear image.
• Power consumption: Emitting infrared pulses and processing images uses battery power. The system would need to be efficient enough for everyday use.
• Security: The sensor must be accurate enough to prevent spoofing with a printed fingerprint or a 3D-printed finger. Apple’s Face ID uses depth mapping to prevent this, and an infrared fingerprint scanner would need similar anti-spoofing measures.

If Apple solves these issues, the technology could appear in a future iPhone, possibly alongside Face ID rather than replacing it.

Alternatives Apple Has Considered

Apple has also patented other biometric ideas, including:

• Under-display Touch ID using acoustic imaging: Uses ultrasound to map the fingerprint through the display.
• Side-mounted fingerprint sensor: A sensor built into the power button, as seen on some iPads.
• Fingerprint sensing in the Apple Watch: A sensor that reads the finger when the watch is held.

The infrared approach is one of several options. Apple may choose to implement a simpler solution, such as a side-button sensor, if the under-display technology proves too costly.

What This Means for Consumers

For now, there is no confirmed product with an infrared fingerprint scanner. The patents are a sign of research and development, not a release date. If Apple does release a device with this technology, it would likely:

• Allow fingerprint unlocking anywhere on the screen.
• Work with wet or oily fingers better than current sensors.
• Potentially enable health features like heart-rate monitoring.
• Keep the same security level as Face ID or Touch ID.

Until then, users who want an iPhone with a fingerprint sensor can choose the iPhone SE (which has Touch ID) or use an Apple Watch to unlock a Face ID iPhone. The patent does not change what is available today.

Frequently Asked Questions

Does the Apple patent mean the next iPhone will have an infrared fingerprint scanner?

No. A patent is a legal protection for an idea, not a product announcement. Apple files many patents that never become products. The patent shows Apple is exploring the technology, but there is no confirmed timeline or device.

How is an infrared fingerprint scanner different from the current Touch ID?

Current Touch ID uses a capacitive sensor that measures electrical differences in the skin. An infrared scanner uses light to take an image of the fingerprint. The infrared version could work through the display, allowing a larger sensing area without a physical button.

Will the scanner work with screen protectors?

Under-display sensors often struggle with thick screen protectors. Apple’s patents do not mention screen protectors, but any future product would likely be designed to work with common glass protectors, as current Face ID and Touch ID do.

Is infrared fingerprint scanning safe?

Yes. The infrared light used is non-ionizing and is similar to what is used in TV remote controls and some health devices. The power levels are low, and the sensor only activates when a finger touches the screen.

Could the infrared sensor be fooled by a photo of a fingerprint?

Probably not. The patent describes capturing the fingerprint through the display, which would require the finger to be at a specific distance and angle. A photo would not reflect infrared light the same way as a real finger. Apple’s security systems also include liveness detection to prevent spoofing.

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