To solve the coating process problems of large-diameter infrared components with DLC film layers and meet the technical requirements of long-focal-length, large-field-of-view optical systems, the radio frequency plasma chemical vapor deposition（RF-PECVD）coating method is adopted. Based on the capacitive coupling plasma standing wave effect and the skin effect mechanism, diamond-like carbon（DLC）film is deposited on the substrate of large-diameter infrared components. By optimizing and improving the uniformity of the plasma electric field, the stress of the film layer is effectively reduced and the reliability and uniformity of the film thickness are improved. According to the environmental test requirements of optical thin film components, high temperature, low temperature, and humidity and heat tests are conducted. After the test, no peeling, folding, or falling off of the film layer is observed. The results show that the large-diameter infrared diamond-like carbon film has good temperature shock and corrosion resistance properties, which meet the normal requirements of optical coating.