A pattern projection light source is disclosed in which a light source (2a); a plurality of mask regions (5) in each of which a light-transmitting portion that transmits light from the light source therethrough is formed in a predetermined pattern; and a plurality of lenses (7) that each form an image of the predetermined pattern of the light-transmitting portion at a predetermined distance are arranged in this order. Since the pattern projection light source includes a plurality of projection optical systems each including a mask region and a lens, a compact and thin pattern projection light source can be realized. Moreover, provision of a plurality of lenses makes it possible to increase the imaging range of a pattern image. Furthermore, an image of the pattern of the light-transmitting portion can be formed clearly on the object.