Clear view screen

Two clear view screens on the navigation bridge of a tugboat

A clear view screen or clearview screen is a glass disk mounted in a window that rotates to disperse rain, spray, and snow. A clear view screen is typically driven by an electric motor at the center of the disk, and is often heated to prevent condensation or icing. Many fishermen call them a "clear sight.

Clear view screens were originally developed in the mid-1930s for automobiles as a better option than standard windshield wipers^[1] but were soon found more suitable for small boats and larger ships. On ships, a clear view screen is usually on the bridge and rotates at high speed (~1500 rpm). Clear view screens are also used in locomotives and rail transport.

A clear view screen was utilised in filming the storm sequence of the movie Ryan's Daughter.^[2]

• 

  Detail image from inside of a clear view screen on R/V Knorr

• 

  A clear view screen of the Type DD51 diesel locomotive in Hokkaidō, Japan

• 

  Sasara Trams of Sapporo Streetcar are equipped with clear view screens

References and Notes

1. "Revolving Disk on Windshield Keeps Off Sleet and Rain" Popular Mechanics, December 1934 bottom-left of pg 873
2. Shooting the storm sequence through a Clearview screen http://ecx.images-amazon.com/images/I/51M9EPHPPWL._SS500_.jpg