New Apple MacBooks Could Gain Customizable Keyboard Sensitivity According To Patent
One solution that's not mentioned in the patent application would be to let users swap out their MacBook's built-in keyboard. That could be a bit cumbersome. Instead of going that route, Apple wants to give users a way of customizing the typing experience of a keyboard, However, that would require "modification of multiple components of each electromechanical actuator specifically because of the electrical, tactile, and mechanical functionality of the depressible key are tightly coupled and interdependent." In short, customizing keyboards as they exist now would be complicated, time consuming, and likely costly.
Apple's solution does exactly that by replacing the electrical contacts and traces with non-contact proximity sensors. This allows key travel and feedback to remain virtually unchanged. To allow for adjustments, Apple's design uses a light emitter directed at the bottom of a reflective keycap. The electrical signal that's generated is processed by the keyboard controller and determines when a key actuates based on the amount of force applied.
Tactile feedback would be processed separately using different materials and an optical sensor mechanism. The end result is a keyboard that's customizable and cost effective to implement.