| 摘要 |
PURPOSE:To cast and draw up a net exactly, by displaying a depth reference marker and a direction marker of a tidal current, on a picture, so that not only a wake of a vessel but also the direction and magnitude of the tidal current can be simultaneously displayed solidly at every prescribed depth on a CRT surface. CONSTITUTION:This display device is provided with an RAM10 for storing a variation of a sailing position in accordance with a result of measurement of a navigating device 8 for measuring a sailing position of its own vessel, a depth setting device 17, an RAM14 for storing a measuring data of an ultrasonic tidal current meter 11 for measuring a flow direction and a velocity of flow in its depth in accordance with a Doppler frequency component contained in a reflected wave from the set depth, an ROM for storing at least a depth reference marker signal and a direction marker signal, a displaying RAM2 for reading and storing the contents of each storing circuit, a CRT1 for displaying the contents of the RAM2, and a CPU7 for processing a data between each circuit. In this state, a depth reference marker is displayed in the vertical direction on the picture from a wake, and a direction marker is displayed toward the direction corresponding to the direction of a measured tidal current from a position corresponding to the prescribed depth of the depth reference marker. |
