Light guide, light guide unit, manufacturing method of light guide unit, and electronic device

1. A light guide comprising:

a light guide main body that guides light input from an incident surface to an exit surface; and

an attachment member that is connected to the light guide main body and comprises an attachment portion that is to be fixed to another member,

wherein an area of a connection surface between the attachment member and the light guide main body is smaller than a cross-sectional area of the attachment portion,

wherein the light further comprises:

a plurality of attachment members that are connected to the light guide main body, and

wherein a cross-sectional area of each of a plurality of connection portions in a thickness direction is the same as or greater than an area of each of a plurality of connection surfaces.

2. The light guide according to claim 1 , wherein a thickness of the attachment member on a side in which the attachment member is connected to the light guide main body is smaller than a thickness of the attachment portion.

3. The light guide according to claim 1 , wherein the light guide main body and the attachment member are integrally formed.

4. A light guide unit comprising:

the light guide according to claim 1 ;

a holding member in which a recessed groove to which the light guide is fitted is formed;

a protrusion that is formed in one of the attachment portion and the recessed groove; and

a hole portion that is formed in an other of the attachment portion and the recessed groove, the protrusion being inserted into the hole portion,

wherein the protrusion is coupled to the hole portion.

5. An electronic device comprising:

a main body of the electronic device; and

the light guide according to claim 1 , that is installed in the main body of the electronic device,

wherein the incident surface of the light guide main body is exposed to outside from the main body of the electronic device.

6. A manufacturing method of a light guide unit, the manufacturing method comprising:

fitting the light guide according to claim 1 to a recessed groove that is formed in a holding member and inserting a protrusion that is formed in one of the attachment portion of the light guide and the recessed groove into a hole portion that is formed in an other of the attachment portion of the light guide and the recessed groove; and

fixing the protrusion and the hole portion using thermal welding.

7. The light guide according to claim 1 , wherein the area of a connection surface of the light guide main body on an area in which the attachment member is connected to the light guide main body is less than the cross-sectional area of the attachment portion.

8. The light guide according to claim 1 , wherein the light guide main body includes:

at least one side face;

a surface; and

a back surface,

wherein the plurality of attachment members are connected to at least one side face of the light guide main body.

9. The light guide according to claim 1 , wherein the attachment member is formed in a direction that is orthogonal to the light guide main body.

10. The light guide according to claim 8 , wherein the back surface includes an inclined plane, and wherein a thickness between the surface of the light guide main body and the back surface increases from the exit surface to the incident surface.

11. The light guide according to claim 1 , wherein the plurality of attachment members are formed in a direction that is orthogonal to the light guide main body.

12. The light guide according to claim 1 , wherein the plurality of attachment members are disposed in parallel with each other.

13. The light guide according to claim 8 , wherein the plurality of attachment members include a surface, and

wherein the surface of the light guide main body is flush with a surface of the plurality of attachment members.

14. The light guide according to claim 1 , wherein the light guide main body is integrally formed with the plurality of attachment members,

wherein the plurality of attachment members are provided on at least one side face of the light guide main body, and

wherein the plurality of attachment members intersect the light guide main body.

15. The light guide unit according to claim 4 , wherein the recessed groove includes:

a first attachment groove; and

a second attachment groove,

wherein in the recessed groove, a main groove portion is formed at a center of the holding member in a longitudinal direction, and

wherein the first attachment groove and the second attachment groove are formed in a direction perpendicular to the main groove portion.

16. The light guide according to claim 10 , wherein the exit surface is disposed in a direction that is orthogonal to the incident surface.

17. The light guide according to claim 1 , wherein the attachment member is connected to the light guide main body in a position that is between the incident surface and the exit surface.

18. The light guide according to claim 1 , wherein a thickness of the attachment portion is greater than a thickness of the connection surface.