Light adjusting apparatus

1. A light adjusting apparatus comprising:

a first substrate that has a first light passage shaped portion for allowing incident light to pass therethrough;

a second substrate that is disposed parallel to the first substrate at a predetermined distance therefrom and has a second light passage shaped portion for allowing incident light to pass therethrough;

a rotating shaft member rotatably attached to the first substrate and the second substrate so as to be perpendicular to substrate surfaces of the first substrate and the second substrate;

a drive section that rotates the rotating shaft member;

an incident light adjusting section that has an engaging surface shaped so as to contact an outside surface of the rotating shaft member, is joined to the outside surface of the rotating shaft member so as to rotate integrally therewith on the engaging surface, is arranged so as to rotate within the predetermined distance along with rotation of the rotating shaft member, and is provided with a light adjusting function; and

a reinforcing portion for increasing a junction area of a joint portion between the rotating shaft member and the incident light adjusting section,

wherein the incident light adjusting section is rotated by the drive section via the rotating shaft member to be displaced to a retracted position which is retracted from an optical path of the incident light passing through the first light passage shaped portion and the second light passage shaped portion and to an inserted position located in the optical path of the incident light to thereby adjust the incident light.

2. The light adjusting apparatus according to claim 1 , wherein the reinforcing portion is provided only in a vicinity of the joint portion between the rotating shaft member and the incident light adjusting section.

3. The light adjusting apparatus according to claim 2 , wherein the reinforcing portion is provided so as to be integral with the incident light adjusting section, and the incident light adjusting section together with the engaging surface is further joined to the rotating shaft member in the reinforcing portion.

4. The light adjusting apparatus according to claim 2 , wherein the reinforcing portion is provided so as to be integral with the rotating shaft member, and the rotating shaft member together with the outside surface is further joined to the incident light adjusting section in the reinforcing portion.

5. The light adjusting apparatus according to claim 3 , wherein the reinforcing portion is a ring-shaped protruding portion that protrudes in an axial direction of the rotating shaft member along the outside surface of the rotating shaft member.

6. The light adjusting apparatus according to claim 5 , wherein the ring-shaped protruding portion comprises a second engaging surface shaped so as to contact the outside surface of the rotating shaft member, and

the incident light adjusting section together with the engaging surface is joined to the second engaging surface to thereby increase the junction area and joined to the rotating shaft member.

7. The light adjusting apparatus according to claim 5 , wherein the ring-shaped protruding portion comprises a second engaging surface shaped so as to include a gap with the outside surface of the rotating shaft member, and

the incident light adjusting section is joined to the rotating shaft member by filling the gap with an adhesive to thereby increase the junction area.

8. The light adjusting apparatus according to claim 6 , wherein the engaging surface and the second engaging surface of the incident light adjusting section comprise a cut-out portion formed in part in the circumferential direction, into which the rotating shaft member can be inserted in a direction crossing the axial direction.

9. The light adjusting apparatus according to claim 7 , wherein the engaging surface and the second engaging surface of the incident light adjusting section comprise a cut-out portion formed in part in the circumferential direction, into which the rotating shaft member can be inserted in a direction crossing the axial direction.

10. The light adjusting apparatus according to claim 4 , wherein the rotating shaft member comprises a different diameter portion having a different cross-sectional area perpendicular to an axial direction of the rotating shaft member,

the reinforcing portion is a stepped surface connecting the different diameter portion and the rest of the rotating shaft member and perpendicular to the axial direction, and

the stepped surface of the rotating shaft member is bonded to a surface perpendicular to the axial direction of the incident light adjusting section.

11. The light adjusting apparatus according to claim 4 , wherein the rotating shaft member comprises a different diameter portion having a different cross-sectional area perpendicular to the axial direction of the rotating shaft member,

the reinforcing portion is a tapered surface connecting the different diameter portion and the rest of the rotating shaft member and inclined with respect to the axial direction,

the engaging surface of the incident light adjusting section is shaped so as to contact the tapered surface, and

the tapered surface of the rotating shaft member is bonded to the engaging surface of the incident light adjusting section.

12. The light adjusting apparatus according to claim 1 , wherein the rotating shaft member is an axial magnet magnetized so as to have different magnetic poles around the axis and is included in the drive section, and

the drive section further comprises a coil core member located in proximity to a side surface of the axial magnet at an end of the core member and a coil wound around the coil core member, and rotates the axial magnet by transmitting a magnetic force generated by passing a current through the coil to the axial magnet via the coil core member.