In 1993, Tokyo Research Laboratory developed a technology for extending the I/O buses of personal computers.

A PC bus is extended by means of an optical fiber, preserving full compatibility with ISA-bus or MicroChannel. Ordinary PC add-in cards can be placed several meters from a PC, to which they are connected via the optical link.
The link converts the parallel signals on the PC's I/O bus into serial format, preserving the coherency of the bus protocol, and then transmits them via an optical fiber. Since the optical communication link is perfectly transparent to add-in cards and software, programs can directly access add-in cards placed at a distance from the PC as if they were installed in the PC box.
The maximum distance is 100 m for ISA-bus and 10 m for MicroChannel.

We also designed a PCI bus version of the optical PC bus extension in 1994.

Optical PC Bus Extension Adapter cards and an optical fiber cable.