US 11,940,120 B2
Desktop illumination device
Takahiro Yoshikawa, Osaka (JP); Kozo Nakamura, Osaka (JP); and Yufeng Weng, Osaka (JP)
Assigned to NITTO DENKO CORPORATION, Osaka (JP)
Appl. No. 18/017,503
Filed by NITTO DENKO CORPORATION, Osaka (JP)
PCT Filed Jul. 19, 2021, PCT No. PCT/JP2021/026903
§ 371(c)(1), (2) Date Jan. 23, 2023,
PCT Pub. No. WO2022/024829, PCT Pub. Date Feb. 3, 2022.
Claims priority of application No. 2020-127348 (JP), filed on Jul. 28, 2020.
Prior Publication US 2023/0280005 A1, Sep. 7, 2023
Int. Cl. F21S 6/00 (2006.01); F21V 8/00 (2006.01)
CPC F21S 6/003 (2013.01) [G02B 6/005 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A desktop illumination device, comprising:
a light source; and
a light guide including a light guide plate and configured to guide light emitted from the light source, wherein the light guide is transparent to visible light and see through such that an area behind the light guide is visible,
wherein the light guide plate has a light incident surface on which the light from the light source is incident, a first main surface from which the light entering from the light incident surface is emitted, and a second main surface opposite the first main surface,
the first main surface is disposed substantially perpendicularly to an installation surface of the desktop illumination device, and
an angle at which an intensity becomes maximum in a light distribution of the light emitted from the first main surface is in a range of −90° or more to less than 0°, in a case where an axis passing through a center of the first main surface and perpendicular to the installation surface is defined as a vertical axis, and in a plane including the vertical axis and perpendicular to the installation surface, a direction parallel to the installation surface is defined as vertical 0°, an upward angle with respect to the vertical 0° is defined as a positive angle, and a downward angle with respect to the vertical 0° is defined as a negative angle.