This paper presents an innovative methodology that incorporates direct time-of-flight technology into intelligent sensing for projectors, along with a lightweight, dual-mode optically integrated LiDAR system. The proposed LiDAR system-on-chip, which utilizes a single-photon avalanche diode and time to digital converter with 0.13 µm bipolar CMOS DMOS technology, integrates an on-chip interframe filter, a common optical platform design, and a lightweight keystone correction assist algorithm. This comprehensive integration enables the system to achieve a measurement range of 11 m with 1% relative precision (simulations indicate the potential to achieve 30 m) in auto-focus mode. Additionally, it facilitates high frame-per-second keystone correction within a range of ±30∘ with an error of ±2∘ under illumination conditions of 20 klux.