Optical module and distance measuring device

Abstract

Resolution is improved while suppressing the number of light emitting elements disposed in an optical module. In the optical module, the light emission unit has a multi-array structure based on a structure in which the light emitting elements are respectively disposed at vertexes forming a quadrangle of which sides facing each other are parallel to each other, a distance between the light emitting elements on a side in a first direction is set to a and a distance between the light emitting elements on a side in a second direction orthogonal to the side in the first direction is set to b, the diffraction element generates diffracted light in an n direction (n is a natural number) and an angle θx formed between one diffraction direction and the side in the first direction satisfies θx=tan(b/na), and when angle differences of two light beams generated by inter-light emission distances a and b are set to φa and φb, respectively, and m is set to a natural number excluding an integral multiple of (2n+1), a diffraction angle φx of the diffracted light satisfies φx=m×sqrt{(nφa)+φb}/(2n+1).