| 摘要 |
PROBLEM TO BE SOLVED: To provide a light emitting device having high emission efficiency to a specific angle range, and an illuminating optical system.SOLUTION: A light emitting device according to the present invention comprises a light emitting element, and a transparent plate provided above the light emitting element. One or more structures having inclined faces are formed on an emission side surface of the transparent plate, and an average inclination angle of the inclined faces of the structures is 40° or more and 90° or less. Also, an illuminating optical system according to the present invention comprises the light emitting device, and an optical member for taking a flux of light emitted from the light emitting device, and a capture angle of the optical member is smaller than 83.8°. |
