Last Thursday Patently Apple posted an IP report titled "Apple is working on possible Future Vision-Related Headsets that will provide Tunable Lenses and offer new Sensors." Today the U.S. Patent Office published a patent application of Apple's that relates to smartglasses or XR devices that may include a lens module with a tunable lens. This is a much deeper dive into Apple's technology relating to their tunable lens system for smartglasses and XR headsets.

Apple notes in their patent background that head-mounted devices typically include lenses with fixed shapes and properties. If care is not taken, it may be difficult to adjust these types of lenses to optimally present content to each user of the head-mounted device.

Fluid-Filled Tunable Lens

Apple's invention published today relates to a tunable lens having a periphery that may include a first lens element, a second lens element, a fluid-filled chamber that is interposed between the first and second lens elements, and a plurality of adjustable fluid-filled bladders that are distributed around the periphery. Each adjustable fluid-filled bladder may be configured to selectively adjust a displacement of the first lens element relative to the second lens element at a respective position along the periphery.

A tunable lens having a periphery may include a lens element that forms part of a fluid-filled chamber, a chassis that extends in a ring around the periphery, and actuators positioned along the periphery between the chassis and the lens element. Each actuator may be configured to adjust a displacement between the chassis and the lens element at a respective position along the periphery. The tunable lens may also include a fluid-controlling component that is configured to adjust an amount of fluid in the fluid-filled chamber to cause a displacement between the chassis and the lens element to remain fixed at the multiple positions along the periphery while a shape of the lens element is changed by the actuators.

A tunable lens having a periphery may include a first lens element, a second lens element, fluid interposed between the first and second lens elements, a chassis that extends in a ring around the periphery, and actuators positioned along the periphery between the chassis and the lens element.

Each actuator may be configured to adjust a displacement between the chassis and the first lens element at a respective position along the periphery. The tunable lens may also include a positioner that is configured to adjust a position of the second lens element to cause the displacement between the chassis and the first lens element to remain fixed at the multiple positions along the periphery while a shape of the first lens element is changed by the actuators.

A stepper motor may include a rotor and first and second subassemblies configured to rotate the rotor. Each one of the first and second subassemblies may include a ring-shaped magnet with a plurality of sections having alternating polarity, a first coil, and a second coil. The ring-shaped magnet may be interposed between the first and second coils.

A tunable lens having a periphery may include a lens element, a ring-shaped chassis that extends around the periphery, bladders positioned along the periphery between the ring-shaped chassis and the lens element, each bladder being configured to adjust a displacement between the ring-shaped chassis and the lens element at a respective position along the periphery, and actuators positioned on the ring-shaped chassis. Each actuator may be adjacent to a respective bladder of the bladders and may be configured to adjust an amount of fluid in its respective bladder.

A tunable lens may include a lens element that forms part of a fluid-filled chamber, one or more actuators configured to change a shape of the lens element, and a fluid-controlling component that is configured to adjust an amount of fluid in the fluid-filled chamber.

The fluid-controlling component may include a flexible bladder with ribs that is aligned with an inlet for the fluid-filled chamber and that has a volume that is configured to contain fluid and a scissor jack portion that is attached to the flexible bladder. The scissor jack portion may be configured to extend in a given direction to shrink the volume of the flexible bladder and push the fluid from the flexible bladder into the fluid-filled chamber.

Apple's patent FIG. 6 below is a top view of an illustrative tunable lens #72-2 with a plurality of fluid-filled bladders #102 (sometimes referred to as actuators 102, hydraulic actuators 102, bladders 102, etc.). In the example of FIG. 6, there are eight fluid-filled bladders distributed around the periphery of tunable lens #72-2 (#102-1 to 102-8.)

A lens shaping element #104 may also be formed around the periphery of the tunable lens. The lens shaping element may be attached between lens element #84 and the bladders. Lens shaping element (sometimes referred to as lens shaper, deformable lens shaper, lens shaping structure, lens shaping member, annular member, ring-shaped structure, etc.) is manipulated by the fluid-filled bladders and in turn manipulates the positioning/shape of lens element. In this way, the curvature of the lens element (and accordingly, the lens power of lens module 72) may be adjusted.

Apple's patent FIG. 8 above is a top view of an illustrative tunable lens with fluid-controlling components and a chassis with fluid channels.

For full details, review Apple's patent application 20250028093.

A Few of Apple's Inventors

• Richard Topliss: Senior Camera Technology Specialist
• Matt Hollands: Display Incubation Engineer
• Daniel Burbridge: Module Systems Engineer
• Gregory Thomas: Senior Area Manager