PURPOSE: To perform the electric characteristic test of a semiconductor photoelectric element under a state close to actual using state by inserting a lens group between a light source and the semiconductor photoelectric element and irradiating the semiconductor photoelectric element with light from the light source at a narrow angle while preventing the semiconductor photoelectric element from being irradiated with scattering light.

CONSTITUTION: A lens group 1 is inserted between a light source 4 and the semiconductor photoelectric element 2. The semiconductor photoelectric element 2 can be irradiated with light from the light source 4 at a narrow angle under a state close to actual using state through the lens group 1 comprising rod lenses inserted between a light source 4 and the semiconductor photoelectric element 2. Consequently, the incident angle of light is limited even for a light receiving element located at a position remote from the center of the semiconductor photoelectric element 2 and the light receiving element is not irradiated with the scattering light. With such method, electric characteristics test can be performed for the semiconductor photoelectric element 2 under a state close to actual using state.