PURPOSE: To reduce dimensions of the light emitting face of a light source body practically, by using a focusing optical system of ≤1 magnifications for a light source such as a light projector to form a light source image and using this focused light source image as an apparent light source.

CONSTITUTION: A convex lens, a concave lens, a convex mirror, or a concave mirror is used as the focusing optical system which generates a small apparent light source. This light source body is used in combination with the optical system of an illumination device such as an illumination tool or a light projector. A convex lens 3a is used as a focusing optical system 3 of the light source and is combined with a convex ens 4a of the illumination device, and the convex lens 4a is so arranged that a focus F2' of the lens 4a is placed near an image 2 (L1', L2'WL6') of a light source 1 (L1, LT, L2WL6) (LT is a contact) generated by the convex lens 3a, and thus, an angle θ2 of spread of beams of the light emitted from the convex lens 4a is made narrower than an angle θ1 including the original light source 1.