What type of core structure do most plastic optical fibers have?

Most plastic optical fibers indeed feature a large core step-index structure. This design simplifies the manufacturing process and enhances light transmission properties suitable for the applications of plastic optical fibers. The large core allows for greater acceptance of light, which effectively accommodates the larger numerical aperture associated with plastic optical fibers. This characteristic is essential in applications where alignment and precision in light transmission may be less stringent, such as consumer products like decorative lighting and simple data connections.

The step-index design contributes to the efficient confining of light within the core due to the clear boundary between the core and cladding, leading to minimal signal loss and improving the overall performance in short-distance data transmission scenarios.