A light receiver array according to the present invention is constituted by array-aligning plural receivers having slow light waveguides of photonic crystals, and a LiDAR device according to the present invention is constituted by linearly arranging a light receiver array and a transmitter. An arranging relationship of plural receivers of the light receiver array is an array-like element formed by array-aligning plural receivers having the slow light waveguides of photonic crystals, and the array alignment is defined by alignment for defining a position relationship between the plural receivers constituting the light receiver array, and orientation for defining a direction of each receiver. A relationship p=λ/sin Δθr is satisfied between the alignment pitch p, wavelength λ of the reception light, and an arrival angle Δθr when a phase difference between reception lights received by waveguide ends of adjacent receivers is one wavelength. Such a constitution that the arrival angle Δθr is equal to a widening angle Δθt of radiation light suitable.