ALS- Automatic Laser Shutdown. To put it simply: if the optical module cannot receive light, it will not emit light. If the optical module can receive light, it will always emit light. Specifically: when the optical fiber is broken and the maintenance personnel are splicing the fiber, ALS is selected, and the optical module emits light intermittently. If the opposite optical module cannot receive light, it will not emit light, thus preventing the optical module from emitting light. It enters people‘s eyes through optical fibers and accidentally injures the eyes of maintenance personnel. When the optical fiber is successfully spliced, the optical module emits light intermittently. After receiving the optical signal, the opposite optical module emits light regularly, and the link is established.

HTF DWDM transmission service boards 400G muxponder, 200G muxponder, 100G transponder, 400G Q-DD OTU, 10G OEO, etc, support ALS function. When repairing optical fibers, it can protect the eyes of maintenance personnel from being hurt.