Camera modules commonly use COB to place image sensors straight on the board, which suits compact IoT sensor nodes. COB technology supports plain digital ICs, analog front ends, and true mixed-signal blocks on the same module. That covers microcontrollers, ADC/DAC paths, radios . Optical module (Figure 1) is an important component in the optical communication system, the main function is to realize the photovoltaic conversion and the monitoring and management of communication signals and other functions. In today's optical fiber network, the application scenarios of optical. COB, BOX, and TO-CAN packaging each offer unique advantages tailored to specific applications. COB packaging integrates components directly onto a PCB, enabling miniaturization and cost efficiency. Compared with conventional processes, the COB process offers high packaging. TOSA: Its main function is to convert electrical signals to optical signals, including lasers, MPD, TEC, isolator, Mux, coupling lenses and other devices, including TO-CAN, Gold-BOX, COC (chip on chip), COB ( chip on board) and other packaging forms. Engineers often call the visible epoxy bump the “black blob,” and the overall.