The HC3511-4K DVI optical terminal developed and manufactured by Beijing HCSTCOM can be used to support uncompressed lossless transmission of signals satisfying DVI 1.0 and HDMI 1.4A protocols. The resolution can support 4Kx2K ultra-high definition. The distance can reach 300 meters in multi-mode and 10KM in single mode. RS232 data bidirectional transmission, optional (USB) KVW mouse keyboard function, can be used for research and development of security projects; the product is widely used in video conferencing system, large screen mosaic system, research and development of security systems, military command and control system, education system, etc.