iFixit iPhone 18 Pro Teardown: Variable Aperture and More

Inside the iPhone 18 Pro: Aperture Mechanics and Cooling Upgrades

iFixit has released its comprehensive teardown of the iPhone 18 Pro, shedding light on significant internal changes including the new variable aperture mechanism and an expanded cooling system. The analysis also highlights potential complications regarding display repairs, suggesting that while Apple has introduced several engineering improvements, some accessibility issues persist for independent technicians.

The most notable camera innovation is the variable aperture, which utilizes six microscopic blades managed by electromagnets similar to those in the optical image stabilization system. Despite their similarities, these systems function independently. During the disassembly process, iFixit demonstrated the fragility of this component when one of the tiny blades detached from the lens stack. This incident underscores the difficulty of performing component-level repairs; if the aperture becomes stuck, users would likely need to replace the entire main camera assembly rather than just the faulty blade.

Another major architectural shift involves the under-display Face ID infrared camera. For the first time in the Pro lineup, Apple has moved the infrared sensor beneath the OLED panel, while retaining the selfie camera and IR dot projector within the Dynamic Island cutout. To maintain visual integrity, Apple removes every other row of pixels above the sensor and applies an IR-pass filter beneath the display layer to block visible light. However, because the filter does not extend to the edge of the opening, iFixit observed an “eclipse effect” under specific microscope settings.

Thermal Redesign and Repairability Concerns

Apple’s approach to thermal management has been significantly reworked for the A20 Pro chip. By placing the silicon die side-by-side with memory modules, the company removed the memory from the SoC’s direct thermal path. This allows the processor to connect directly to a vapor chamber that boasts three times the surface area of its predecessor in the iPhone 17 Pro. The teardown reveals thermal material pressing the A20 Pro firmly against this extensive cooling structure, which spans much of the device’s interior.

Despite these advancements, iFixit encountered a concerning issue during the teardown. The team reported that the plastic frame surrounding the display was damaged on three out of four units opened. While Apple has utilized this same plastic frame since the iPhone 15 Pro and other teardowns have not reported similar damage, iFixit suggests the improved thermal system may be drawing heat away from the display adhesive more aggressively than before. If the frame is compromised, it can prevent the display from sitting flush upon reassembly and potentially void the device’s water resistance rating.

Accessibility remains a mixed bag for DIY enthusiasts. Although the iPhone 18 Pro retains favorable features like a glue-free battery tray and modular camera assemblies, many components are still difficult to access. Notably, replacing the USB-C port requires removing nearly all internal parts. Consequently, iFixit has assigned a provisional repairability score of 7 out of 10 to both the iPhone 18 Pro and Pro Max. This rating reflects ongoing testing and uncertainty regarding whether the display frame issue is an isolated anomaly or a broader trend affecting future units.