Focusing control device, focusing control method, focusing control program, lens device, and imaging device

A non-transitory computer readable medium storing a focusing control program causing a computer to:

• obtain correlation values between a first signal group output from a plurality of first signal detection sections, which receives one of a pair of luminous fluxes passing through different portions arranged in one direction of a pupil region of an imaging optical system including a focus lens and detects signals, and a second signal group output from a plurality of second signal detection sections, which receives other one of the pair of luminous fluxes and detects signals, for different shift amounts while shifting the first signal group and the second signal group in one direction by arbitrary amounts, the plurality of first signal detection sections and the plurality of second signal detection sections being formed in a focus detection area of a sensor,
• obtain an accumulative value of the correlation values included in each of a plurality of division areas obtained by dividing a graph of the correlation values in which the shift amounts are represented on a first axis in a direction of the first axis, and
• perform focusing control by controlling the focus lens based on the accumulative value obtained.