Optical CPU Unified Architecture Minimal 8-State Multi-Valued Digital Optical Computing Model

This work proposes a minimal yet extensible architecture for a general-purpose optical CPU based on an 8-state multi-valued digital cell implemented using RGB light. The model preserves compatibility with existing electronic CPUs through a minimal instruction set and an ADD(mod8)-based arithmetic core, while reserving an undefined “optical mode” as intentional design whitespace for future extensions. The architecture enables asynchronous, clockless operation by relying on the constant propagation speed of light and CMOS-based state readout. Intermediate optical states—such as interference, intensity, phase, and temporal-width variations—are treated not as quantum-mechanical superpositions but as classical optical processes that collapse into 8 discrete states at readout. A feasibility analysis of single-cell implementation, a minimal instruction encoding scheme, and a simplified noise model are provided to demonstrate the structural soundness of the minimal specification.