Liquid level measuring apparatus, method, and program

Abstract

Provided is a liquid level measuring technique capable of measuring a liquid level with high accuracy even if a liquid stored in a container is boiling. The liquid level measuring apparatus includes: ultrasonic sensors each configured to transmit and receive an ultrasonic wave, the ultrasonic sensors being respectively set at a plurality of positions on an outer surface of a container that stores a liquid; a transmission/reception controlling unit configured to set, as a target, any one of the ultrasonic sensors at the plurality of positions and control the transmission and reception of the ultrasonic wave of the target; an intensity detecting unit configured to detect an intensity of the ultrasonic wave that satisfies at least 2≦N (N: natural number), of the ultrasonic waves that are reflected N times on an inner surface of the container; a gas/liquid determining unit configured to determine which of the liquid and a gas a reflection point on the inner surface is in contact with, on a basis of the detected intensity of the ultrasonic wave; and a level determining unit configured to determine a liquid level of the liquid on a basis of gas/liquid determination results respectively derived by the ultrasonic sensors at the plurality of positions.