| 摘要 |
PROBLEM TO BE SOLVED: To provide an illumination device that can achieve sufficiently high levels both in anti-glare property and illuminance.SOLUTION: An illumination device 1 of the present invention includes: a linear-shaped light source unit 10; and a light diffusion body 20 provided on a light emission side of the light source unit 10. The light diffusion body 20 includes thereon: a first protruded and recessed pattern 21a in which protrusions and recessions are repeatedly formed along a direction in a range of ±20° with respect to an orthogonal direction to a longitudinal direction of the light source unit 10; and a second protruded and recessed pattern 22a in which protrusions and recessions are repeatedly formed along a direction in a range of ±20° with respect to the longitudinal direction of the light source unit 10. The first protruded and recessed pattern 21a has a tip of each protrusion facing the light source unit 10 side, whereas the second protruded and recessed pattern 22a has a tip of each protrusion facing the opposite side of the light source unit 10. Further, the second protruded and recessed pattern 22a has the most frequent pitch A of the protruded and recessed pattern of more than 1.0 μm and 30 μm or less, and has a ratio (B/A) of 0.1 to 3.0, which is the ratio of an average depth B of the protrusions and recessions to the most frequent pitch A. |
