A wiring pattern inspection apparatus comprises a light source, a parallel light guiding section which guides light from the light source substantially in parallel, and a light extraction section which extracts a transverse wave light component crossing the light guiding direction at right angles from the light guided by the parallel light guiding section and which converts the transverse wave light component into a specific polarized component and which irradiates a work with the specific polarized component and which extracts a vertical wave light component from reflected light obtained by reflecting the emitted specific polarized component by the work.