| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem that it is sensuously difficult to view a display image clearly in a display of a conventional fish finder because a ratio of a vertical scale and a horizontal scale is not fixed. <P>SOLUTION: A depth range data output part 17 generates depth range data by a reflected wave signal read out from a first memory 10, and a reflected wave signal with ship speed data read out from the first memory 10 is inputted to a horizontal scale calculation part 18 to calculate a horizontal scale in accordance with a depth. In accordance with the calculated value, an expansion/contraction rate of the horizontal scale, that is, an expansion/contraction rate of a width of an image to be displayed on a display device 16 is calculated by a horizontal scale expansion/contraction part 19. The reflected wave signal read out from the first memory 10 is expanded/contracted in accordance with the calculated expansion/contraction rate, and the expanded/contracted reflected wave signal is inputted to a second memory 20. The expanded/contracted reflected wave signal read out from the second memory 20 is inputted to an expanded/contracted image generation part 21 and is converted into an image signal. A sea bottom C in a screen illustrated by B in FIG. 2 on the display device 16 has the horizontal scale matched in accordance with depth in FIG. 2 and is expanded/contracted into the horizontal scale matching the depth as illustrated by a sea bottom D in FIG. 3, so that display approximating an actual configuration of the sea bottom can be provided. <P>COPYRIGHT: (C)2012,JPO&INPIT |
