Zero Impact Typing.
Repetitive Strain Injury (RSI) is not caused by finger movement. It is caused by thousands of daily micro-impacts against a solid piece of plastic. By moving typing into the optical domain, we permanently drop actuation force to zero grams.
The Mechanics of RSI
When you type on a traditional mechanical keyboard, your fingers must overcome a physical spring (typically 45g to 60g of force). More critically, the finger abruptly stops when the switch "bottoms out." This rapid deceleration sends a micro-shockwave through the tendons of the hand and wrist.
At an average typing speed of 80 WPM for 6 hours a day, a developer or writer strikes the keys roughly 144,000 times. That is over 6,480 kg (14,285 lbs) of cumulative force exerted by the smallest muscles in the human body every single day.
Actuation Force Comparison (Industry Averages)
Decoupling Posture from the Input Device
Split ergonomic keyboards attempt to solve wrist pronation, but you are still anchored to a fixed slab of plastic on a desk. KeyboardHand's 850nm IR array maps a 60cm wide 3D space in front of the sensor.
You can type on the surface of your desk. You can lean back and type on your lap. You can type on the armrests of your chair. Because the system tracks the relative geometry of your hands rather than strikes against a physical grid, your spatial posture is completely unrestricted. This makes it a crucial tool for workplace accessibility.
"The transition from a 45g Topre switch to optical chording took me 4 weeks to master, but my carpal tunnel symptoms vanished within 10 days. The complete elimination of bottom-out shock is something you can physically feel in your forearms."
— Dr. E. Aris, Occupational Ergonomics, 2023