Video High Density
Similar to the RCA's CED, the signal on the VHD is recorded by varying capacitance on the disc. However, unlike the CED, the VHD does not contain any groves and the needle is made of diamond instead of titanium. Instead of having grooves, the needle is kept on track electronically so the needle does not have to actually touch the disc therefore resulting in less wear on the disc and on the needle. In one rotation of the disc, 2 frames of picture and audio were read.