Illuminator with light source units radially arranged at a reference point of a base frame

1. An illuminator comprising:

a plurality of light source units that include:

a light guide; plate that includes:

an internal side positioned radially at a most inside position;

an external side positioned radially at a most outside position; and

a lateral side radially connecting the internal side and the external side; and

a plurality of point light sources arranged on the lateral side of the light guide plate, each of the plurality of light source units being configured such that light introduced from the plurality of point light sources to the light guide plate is adapted to exit from a main surface of the light guide plate,

wherein the plurality of light source units are radially positioned at a reference point of a base frame.

2. The illuminator according to claim 1 , wherein

the light guide plate of each of the plurality of light source units is configured so that the external side of the light guide plate positioned farthest in a radial direction from the reference point of the base frame is made to have a wider width than the internal side of the light guide plate facing the reference point of the base frame.

3. The illuminator according to claim 1 , wherein

a space defined between each of the lateral sides of the light guide plates of adjacent light source units is made constant from the internal side of the light guide plate facing the reference point of the base frame to the external side of the light guide plate positioned farthest in a radial direction from the reference point of the base frame.

4. The illuminator according to claim 1 , wherein

the base frame has a circular configuration in a plan view, a center of the base frame is the reference point.

5. The illuminator according to claim 1 , wherein

the plurality of point light sources of each of the plurality of light source units are arranged along each of lug portions that is radially placed on the base frame.

6. The illuminator according to claim 5 , wherein

each of the lug portions is shaped to have a wall configuration, and

the plurality of point light sources of the plurality of light source units positioned adjacent to each other are arranged on two side surfaces of the lug portions.

7. The illuminator according to claim 1 , wherein

a frame member is arranged to cover between each of the lateral sides of the light guide plates of adjacent light source units,

the frame member projecting in a direction that light exits from the main surface of the light guide plate to form a projected surface, and

the projected surface of the frame member includes a pair of inclined surfaces that taper while moving away from the main surface of the light guide plate in the direction that light exits.

8. The illuminator according to claim 1 , wherein

an interval between each individual point light source in the plurality of point light sources is adapted to shorten when moving from each of the internal sides of the light guide plates facing the reference point of the base frame to each of the external sides of the light guide plates positioned farthest in a radial direction from the reference point of the base frame.