Fish finder, fish length measuring device, fish finder, and fish finder

摘要

PROBLEM TO BE SOLVED: To realize a fish finder capable of efficiently acquiring information because a measurement range is automatically set. SOLUTION: A single fish detection unit 41 for detecting a single fish from echo information obtained from ultrasonic waves transmitted in the depth direction at a predetermined time interval, and two-dimensionally arranged in the depth direction and the time axis direction. A unit number of individual fish calculating unit 42 for calculating the number of individual fish for each of a plurality of units, and a reference unit for detecting a reference unit based on the number of unit fish calculated for each of the plurality of units by the unit number of individual fish calculating unit 42 A detection unit 43 and a measurement range setting unit 44 that sets a measurement range based on the reference section detected by the reference section detection unit 43 are provided. [Selection diagram]