An optical module includes a variable wavelength interference filter that has a pair of reflection films facing one another, and that emits light with a wavelength according to the gap dimensions of the pair of reflection films; an incident side optical system as a negative power lens group that guides an incident luminous flux to the variable wavelength interference filter; and a light guiding optical system as a positive power lens group on which a luminous flux passing through the variable wavelength interference filter is incident, in which the incident side optical system guides the incident luminous flux to the variable wavelength interference filter as a luminous flux in which the principal ray is parallel with respect to the optical axis (central optical axis) orthogonal to the pair of reflection films and that is scattered with respect to the principal ray, and the light guiding optical system makes the luminous flux scattered with respect to the principal ray a parallel luminous flux.