Light Diffusion Unit for Scanning Display Luminance Control

The patent applies parameter changes by establishing a specific mathematical relationship between the angle formed by optical paths (θ), the resolution angle of the eye (α), and the arrangement pitch of light diffusion channels (P). The condition θ ≥ α ensures that the angular separation between light paths from adjacent channels is sufficient to prevent luminance unevenness while maintaining manufacturability. This parameter-based approach transforms a precision control problem into a design specification problem.

The patent resolves this contradiction by changing the critical parameter from beam diameter to angular separation. Instead of controlling luminance uniformity through beam size, the invention establishes that the angle θ between optical paths through adjacent channels must satisfy θ ≥ α (where α is the resolution angle of the eye). This parameter substitution allows high resolution to be achieved through smaller beam diameters without causing luminance unevenness, as long as the angular separation condition is met.

The patent resolves this contradiction by establishing a design criterion that links arrangement pitch (P) to the resolution angle (α) through the relationship θ ≥ α. This allows engineers to determine the minimum acceptable pitch for a given channel configuration, or conversely, to optimize pitch to achieve desired channel density while ensuring luminance uniformity. The principle transforms a trade-off into a constrained optimization problem with a clear solution boundary.