Digital Polymerase Chain Reaction （dPCR） is a molecular biology technique that enables absolute quantification. However, conventional dPCR fluorescence detection systems face challenges in achieving an optimal balance among detection throughput, speed, system size, and cost. In particular, traditional illumination system designs are constrained by limitations in illumination area, uniformity, volume, and switching response, which affect the overall performance and applicability of the equipment. To address these issues, this study proposes a portable dPCR fluorescence detection system optimized for large-field imaging based on an LED excitation design with uniform illumination. This system aims to reduce size and costs without compromising detection speed and throughput. Utilizing a high-integration ring-shaped LED light source arrangement, the system achieves uniform illumination across an 18 mm × 18 mm field of view for three fluorescence channels（FAM, HEX, ROX）, with actual illumination uniformity exceeding 90%, and supports rapid three-channel switching.Compared with traditional illumination modules, the LED-based uniform excitation illumination offers advantages in miniaturization, cost-efficiency, and integration, making it suitable for various fluorescence detection applications and advancing the future development of dPCR technology.