US Patent 7495997 Light pipe display for sonar

A light pipe device for fish sonar that displays information such as depth and density of detected objects. The device includes a motor with a rotary shaft, a shaft position sensor, a light conducting pipe fixed to the rotary shaft opposite the luminous tip of the pipe, a light source, and a front panel. Using this device, when a controller detects an object the controller causes the light source to turn on and off as the luminous tip revolves beneath the front panel. Light is transferred to the tip and front panel to indicate information regarding the object.