What type of interface is common on an optical power meter besides RS-232 ports?

The common type of interface found on an optical power meter, besides RS-232 ports, is a USB interface. This is because USB connections provide a standard method of connecting devices to computers and other equipment, offering advantages such as faster data transfers and ease of connectivity. USB interfaces are widely used in various electronic devices, including optical power meters, to facilitate more straightforward communication with computers for data logging, analysis, and reporting.

Other options, while they may exist in some specialized equipment, are not as universally utilized in optical power meters. The USB interface's predominance is due to its versatility and compatibility with a wide range of devices and platforms, making data transfer more efficient for technicians and engineers working with optical networks.