Inquiry Before Buying Global Step-Index Multimode Fibers Market Size, Share and Trends Analysis Report, By Type (Core Diameter 100 ?m, Core Diameter 200 ?m, Core Diameter 600 ?m, Core Diameter 800 ?m, and Others), By Application (Medical Devices, Industrial Sensors, Avionic Sensors, Research Instruments, Spectroscopy, Radiation Analysis, and Others), Forecast (2021-2027)