On-board display device
View Patent ↗An on-board display device installable in a vehicle cabin of a vehicle includes a liquid crystal panel and a light source. The liquid crystal panel displays an image of an outside of the vehicle, the image having been captured by a camera. The light source illuminates the liquid crystal panel. A direction of maximum luminance of the light source is a direction passing through an inside of an eye range preset in the vehicle. An equi-luminance line has a shape longer in a second direction that intersects a first direction than in the first direction in a luminance distribution map that represents luminance of the light source in each direction represented by a polar angle and an azimuth angle. The second direction and a longitudinal direction of an aggregate of points which represent polar angles and azimuth angles of tangential lines of the eye range, the tangential lines passing through the center of the liquid crystal panel, on the luminance distribution map are inclined to a same side with respect to a longitudinal direction of the liquid crystal panel.
1. An on-board display device for a vehicle, comprising:
a liquid crystal panel that displays an image; and
a light source that illuminates the liquid crystal panel,
wherein
a direction of maximum luminance of the light source passes through an inside of an eye range preset in the vehicle,
wherein a longitudinal direction of an equi-luminance line on a luminance distribution map and a longitudinal direction of an aggregate of points corresponding to a contour of the eye range on the luminance distribution map are inclined to a same side,
the equi-luminance line representing luminance of the light source in each direction represented by a polar angle and an azimuth angle,
the eye range statistically representing distributions of driver's eye positions,
the aggregate of points representing polar angles and azimuth angles of tangential lines of the eye range, the tangential lines passing through a center of the liquid crystal panel, and
the direction of the maximum luminance of the light source is one obliquely upward direction only with respect to a normal of a display plane of the liquid crystal panel.
2. The on-board display device according to claim 1 , wherein an inclination in the longitudinal direction of the equi-luminance line and an inclination in the longitudinal direction of the aggregate of points on the luminance distribution map are substantially same.
3. The on-board display device according to claim 1 , wherein the direction of the maximum luminance of the light source passes substantially through a center of the eye range.
4. The on-board display device according to any one of claim 1 , wherein the normal of the display plane of the liquid crystal panel passes through an outside of the eye range.
5. The on-board display device according to claim 1 , wherein the normal of the display plane of the liquid crystal panel passes through the inside of the eye range.
6. The on-board display device according to claim 1 , wherein a luminance of the light source in at least one position in the contour of the eye range is 50% or more of the maximum luminance of the light source.
7. The on-board display device according to claim 6 , wherein a luminance of the light source in a direction of a straight line passing through a center of the liquid crystal panel and at least one position in the contour of the eye range is 50% or more of the maximum luminance of the light source.
8. The on-board display device according to claim 1 , wherein
the light source includes:
a planar light emitter that emits light from a light emitting surface of the planar light emitter; and
a reverse prism-shaped prism sheet that is located between the liquid crystal panel and the light emitting surface of the planar light emitter, and has a prism surface located between the reverse prism-shaped prism sheet and the light emitting surface.