Positive/negative binocular fusional C-optotypes and 2D planar C-optotypes on transient accommodation and stability in adult eyes: implications for myopia prevention and control

Negative fusional C-optotypes induce ciliary muscle relaxation to reduce TAC, while positive fusional C-optotypes enhance accommodation-convergence coordination to increase TAC. The red-blue 3D-based non-contact training mode exhibits good safety (median visual fatigue scores: 0-1 across all tests) and provides a novel dual-directional (relaxation-activation) strategy for myopia prevention and control.