Vehicle light bar with straight and curved frame portions

1. A lighting apparatus for mounting on a vehicle cab, the apparatus comprising:

a frame having a straight central portion and first and second curved end portions on either end of the straight central portion, the straight central portion having a central portion length, the frame having a forward facing light mounting surface, the first and second curved end portions being curved rearwardly relative to the straight central portion;

a plurality of central light sources mounted on the straight central portion, the central light sources each having a light emitting axis projecting forward from and perpendicular to the central portion length so that the light emitting axes of the plurality of central light sources project parallel to each other;

a plurality of first end portion light sources mounted on the first curved end portion; and

a plurality of second end portion light sources mounted on the second curved end portion;

wherein the frame includes cooling fins extending rearward, the frame having a cross-section shape such that a cross-sectional profile of the rear ends of the fins as defined by an imaginary profile line joining the rear ends of the fins has a decrease in fin length adjacent upper and lower edges of the cross section causing a concave step in the imaginary profile line.

2. The apparatus of claim 1 , wherein:

the frame is a continuous extrusion from an end of the first curved end portion to an end of the second curved end portion.

3. The apparatus of claim 1 , further comprising:

a transparent cover mounted on the frame in front of the light sources;

upper and lower trim strips attached to upper and lower front edges of the frame to retain the transparent cover; and

upper and lower support pads protruding forward from the upper and lower trim strips, respectively, the support pads being located along the straight central portion of the frame nearer to the first and second curved end portions than to a center of the frame.

4. The apparatus of claim 1 , further comprising:

first and second end brackets, each bracket having an upper flange configured to attach to ends of the first and second curved end portions of the frame, and each bracket having a lip configured to attach to an A-pillar of the vehicle cab on which the apparatus is to be mounted.

5. The apparatus of claim 1 , wherein:

the frame has a frame length from an end of the first curved end portion to an end of the second curved end portion, and the central portion length is at least 40% of the frame length.

6. The apparatus of claim 5 , wherein:

the central portion length is at least 45% of the frame length.

7. The apparatus of claim 5 , wherein:

the central portion length is at least 22 inches.

8. The apparatus of claim 7 wherein:

each of the first and second curved end portions of the frame has an end portion length of at least 12 inches.

9. The apparatus of claim 1 , wherein:

at least a majority of the central light sources are each a spot light source;

at least a majority of the first end portion light sources are each a diffuse light source;

at least a majority of the second end portion light sources are each a diffuse light source; and

the spot light sources and diffuse light sources are defined relative to each other, with the spot light sources being more directionally concentrated than the diffuse light sources.

10. The apparatus of claim 9 , wherein:

the plurality of first end portion light sources includes at least one spot light source adjacent the central light sources; and

the plurality of second end portion light sources includes at least one spot light source adjacent the central light sources.

11. The apparatus of claim 9 , wherein:

the first end portion light sources each have a light emitting axis projecting forward from and perpendicular to the first curved end portion; and

the second end portion light sources each have a light emitting axis projecting forward from and perpendicular to the second curved end portion.

12. The apparatus of claim 9 , wherein:

all of the central light sources are spot light sources.

13. The apparatus of claim 12 , wherein:

the plurality of first end portion light sources includes at least one spot light source adjacent the central light sources; and

the plurality of second end portion light sources includes at least one spot light source adjacent the central light sources.