What instrument is a group of either red or colorless parallel rods that together act as a cylinder?

Maddox rod is the group of either red or colorless parallel glass rods together act as a cylinder to detect muscle imbalance.

The Maddox rod check can be accustomed subjectively to observe and live a latent, manifest, horizontal or vertical abnormalcy for near and distance. The check is predicated on the principle of diplopic projection.

Maddox Rod consists of a series of urban center cylinder lenses about three millimeter in diameter, mounted in an exceedingly trial frame lens or in an exceedingly refactor head. A spot of sunshine viewed through the Maddox Rod seems as elongated streak. The Maddox Rod is usually red in color.