Vehicle pillar structure

1. A vehicle pillar structure comprising:

a pillar portion, the pillar portion extending in parallel with an outer side end portion in a vehicle transverse direction of a windshield glass and, as viewed from a longitudinal direction of the pillar portion, having a hollow structure, and the pillar portion comprising:

an outer side wall forming a wall portion at a vehicle outer side of the pillar portion;

a solid inner side wall forming a wall portion at a vehicle cabin side of the pillar portion; and

a pair of side walls linking the outer side wall and the inner side wall together, wherein:

at least a portion of the outer side wall is an outer side transparent portion,

at least a portion of the inner side wall is an inner side transparent portion that is disposed so as to face the outer side transparent portion as viewed by a driver, and

portions of the pillar portion other than the outer side transparent portion and the inner side transparent portion are high-strength portions that have a higher flexural strength than the outer side transparent portion and the inner side transparent portion.

2. The vehicle pillar structure according to claim 1 , wherein:

a first holding portion is provided at one of the pair of side walls, the first holding portion protruding towards an inner side of the hollow structure, and holding a vehicle transverse direction outer side end portion of the windshield glass,

a second holding portion is provided at another of the pair of side walls, the second holding portion protruding towards the inner side of the hollow structure, and holding a sealing component, and

the high-strength portions are formed from an opaque material.

3. The vehicle pillar structure according to claim 2 , wherein:

transverse direction outer side end portions of the outer side wall and the inner side wall are connected to the pair of side walls, and

the transverse direction outer side end portions are configured by the high-strength portions.

4. The vehicle pillar structure according to claim 1 , wherein a plate thickness of the outer side transparent portion and the inner side transparent portion is from 0.5 mm to 5 mm.

5. The vehicle pillar structure according to claim 4 , wherein:

in a planar cross-sectional view from a vehicle upper side, the outer side transparent portion is formed in a curved shape and protrudes towards the vehicle outer side, and the inner side transparent portion is formed in a curved shape and protrudes towards a vehicle cabin inner side, and

a radius of curvature of the outer side transparent portion and of the inner side transparent portion is 500 mm or more.

6. The vehicle pillar structure according to claim 1 , wherein:

the outer side transparent portion and the inner side transparent portion are formed from a transparent resin material, and

the high-strength portions are formed from carbon fiber-reinforced plastic.

7. The vehicle pillar structure according to claim 3 , wherein, in a planar cross-sectional view from a vehicle upper side:

the outer side wall is provided with the transverse direction outer side end portions on both sides of the outer side transparent portion, and

the inner side wall is provided with the transverse direction outer side end portions on both sides of the inner side transparent portion.