Before revision: Gregg 1958 Laserdisc technology, using a transparent disc, Transparent recording disc, 1969. was invented by David Paul Gregg in 1958 (and patented in 1961 and 1990).
After revision: Gregg 1958 Laserdisc technology, using a transparent disc, Transparent recording disc, 1969. was invented by David Paul Gregg in 1958 (and patented in 1970 and 1990).