| 摘要 |
Embodiments provide a light-emitting device including a light source, and a lens disposed above the light source. The lens includes a lower part having a first recess formed in an optical-axis direction so as to face the light source, and an upper part having a second recess formed in the optical-axis direction so as to be opposite to the lower part. The first recess and the second recess are spaced apart from each other by a separation distance within a range from 1 mm to 4.7 mm on an optical-axis. |
