The present invention relates to a laser light source and others for decreasing wavelength-by-wavelength differences of focal positions of focused components in collimating and then focusing polychromatic light with a wide spectrum width. The laser light source includes a collimator device, in which relative positions of emergence of a laser beam emitted from a polychromatic light source and a collimating lens composed of an achromatic lens can be adjusted at a 10 μm level or less.