As shown in FIG. 7E, an emitting direction of a designated point of the first portion 100p1 and an emitting direction of a symmetric point of the second portion 100p2 symmetric to the designated point are symmetric in direction in the top view with respect to the Y-axis. In the embodiment, the emitting direction may be defined as a direction towards which the LED chips face. Since the LED chips face the main lighting face Lm, the emitting direction may also be defined as the normal direction of the main lighting face Lm. For example, the designated point (x1, y1) of the first portion 100p1 has an emitting direction ED towards right in FIG. 7E, and the symmetric point (x2, y2) of the second portion 100p2 has an emitting direction ED towards left in FIG. 7E. The emitting direction ED of the designated point (x1, y1) and the emitting direction ED of the symmetric point (x2, y2) are symmetric with respect to the Y-axis. In addition, the designated point (x3, y3) of the third portion 100p3 has an emitting direction ED towards a lower-left direction in FIG. 7E, and the symmetric point (x4, y4) of the fourth portion 100p4 has an emitting direction ED towards a lower-right direction in FIG. 7E. The emitting direction ED of the designated point (x3, y3) and the emitting direction ED of the symmetric point (x4, y4) are symmetric with respect to the Y-axis. In addition, an emitting direction ED of any designated point of the first portion 100p1 and an emitting direction ED of a corresponding symmetric point of the second portion 100p2 symmetric to the designated point are symmetric in direction in the top view with respect to the Y-axis. An emitting direction ED of any designated point of the third portion 100p3 and an emitting direction ED of a corresponding symmetric point of the fourth portion 100p4 symmetric to the designated point are symmetric in direction in the top view with respect to the Y-axis.
