Camera Requirements
To accurately capture 10 digits moving at high speed, standard webcams fail. We need specific sensor hardware.
Why Global Shutter is Mandatory
Rolling shutter cameras expose the sensor line-by-line. When a finger moves rapidly, this causes temporal shearing (the "jello effect"). A global shutter exposes all pixels simultaneously.
Common Mistakes
- Relying on RGB sensors: RGB struggles with complex backgrounds. NIR (Near-Infrared) is required for reliable tracking regardless of room lighting.
- Sub-90Hz Framerates: A fast typist's finger accelerates at over 2G. At 30Hz, the finger moves several centimeters between frames, destroying tracking fidelity.
Required Specs
| Spec | Requirement |
|---|---|
| Framerate | >= 90Hz (120Hz preferred) |
| Shutter | Global |
| Spectrum | Near-Infrared (NIR) for low-light |
| FOV | >= 120 degrees vertical |
Interactive Tool: Motion Blur Calculator
Assumes perpendicular motion to the camera axis.
FAQ
Can I use standard RGB webcams?
Yes, but NIR provides better contrast against complex backgrounds and works in low ambient light. RGB relies entirely on algorithmic background subtraction which adds compute overhead.
What is the minimum FOV?
For a lap-anchored virtual keyboard, the headset's downward-facing cameras must have at least a 120-degree vertical FOV to keep the hands in frame without forcing the user to look down.
Comprehensive Technical Directory
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