Instrumental device

1. An instrumental device comprising:

a dial plate formed in a circular plate shape, and on which indexes indicating a condition of a mobile object are arranged in a circumferential direction of the dial plate;

a case provided with a concave formed in a concave groove shape along the indexes, and to which the dial plate is attached so as to cover an opening of the concave; and

a light source provided on a rear side of the dial plate in the concave, opposite to the index, and emitting light toward the index,

wherein the case is provided with a light shield interposed between the index and the light source and facing the light source,

wherein at least a part of an outer periphery of the light shield is formed in an arc shape so that a distance from an outer periphery of the concave is constant, and

wherein an inner peripheral wall of the concave is provided with a first inclined wall inclined in a direction approaching the dial plate as extended outward, and a second inclined wall inclined in a direction approaching the dial plate as extended inward.

2. The instrumental device as claimed in claim 1 ,

wherein the index is positioned at an outside or an inside of the opening,

wherein the inner peripheral wall of the concave is so provided as to reflect light from the light source,

and

wherein an inclination of one wall provided with the index of the first and second inclined walls is formed smaller than an inclination of the other wall away from the index.

3. The instrumental device as claimed in claim 1 , wherein an inner periphery of the light shield is formed in an arc shape projecting outward.

4. The instrumental device as claimed claim 2 , wherein an inner periphery of the light shield is formed in an arc shape projecting outward.

5. The instrumental device as claimed in claim 1 , wherein the outer periphery of the light shield is provided with a round portion of which distance from the light source becomes longer as being away from a center portion of the outer periphery of the light shield toward an end of the outer periphery of the light shield.

6. The instrumental device as claimed in claim 2 , wherein the outer periphery of the light shield is provided with a round portion of which distance from the light source becomes longer as being away from a center portion of the outer periphery of the light shield toward an end of the outer periphery of the light shield.

7. The instrumental device as claimed in claim 3 , wherein the outer periphery of the light shield is provided with a round portion of which distance from the light source becomes longer as being away from a center portion of the outer periphery of the light shield toward an end of the outer periphery of the light shield.

8. The instrumental device as claimed in claim 4 , wherein the outer periphery of the light shield is provided with a round portion of which distance from the light source becomes longer as being away from a center portion of the outer periphery of the light shield toward an end of the outer periphery of the light shield.

9. The instrumental device as claimed in claim 2 , further comprising:

a pair of legs configured to connect the light shield and the concave and to reflect the light from the light source to the first or second inclined wall, said legs respectively projected outward from both ends of the outer periphery of the light shield.

10. The instrumental device as claimed in claim 3 , further comprising:

a pair of legs configured to connect the light shield and the concave and to reflect the light from the light source to the first or second inclined wall, said legs respectively projected outward from both ends of the outer periphery of the light shield.

11. The instrumental device as claimed in claim 4 , further comprising:

a pair of legs configured to connect the light shield and the concave and to reflect the light from the light source to the first or second inclined wall, said legs respectively projected outward from both ends of the outer periphery of the light shield.

12. The instrumental device as claimed in claim 5 , further comprising:

a pair of legs configured to connect the light shield and the concave and to reflect the light from the light source to the first or second inclined wall, said legs respectively projected outward from both ends of the outer periphery of the light shield.

13. The instrumental device as claimed in claim 6 , further comprising:

a pair of legs configured to connect the light shield and the concave and to reflect the light from the light source to the first or second inclined wall, said legs respectively projected outward from both ends of the outer periphery of the light shield.

14. The instrumental device as claimed in claim 7 , further comprising:

a pair of legs configured to connect the light shield and the concave and to reflect the light from the light source to the first or second inclined wall, said legs respectively projected outward from both ends of the outer periphery of the light shield.

15. The instrumental device as claimed in claim 8 , further comprising:

a pair of legs configured to connect the light shield and the concave and to reflect the light from the light source to the first or second inclined wall, said legs respectively projected outward from both ends of the outer periphery of the light shield.