US 11,940,533 B2
Proximity sensor including light shielding walls
Yoshitsugu Uedaira, Kyoto (JP)
Assigned to Rohm Co., Ltd., Kyoto (JP)
Filed by Rohm Co., Ltd., Kyoto (JP)
Filed on Aug. 30, 2019, as Appl. No. 16/556,621.
Claims priority of application No. 2018169778 (JP), filed on Sep. 11, 2018.
Prior Publication US 2020/0081122 A1, Mar. 12, 2020
Int. Cl. G01S 17/04 (2020.01); G01S 7/481 (2006.01); G01S 7/4865 (2020.01); G01S 7/497 (2006.01); G01S 17/06 (2006.01); H01S 5/023 (2021.01); H01S 5/0233 (2021.01); H01S 5/0683 (2006.01); H01S 5/183 (2006.01); H01S 5/02257 (2021.01); H01S 5/0235 (2021.01)
CPC G01S 17/04 (2020.01) [G01S 7/4813 (2013.01); G01S 7/4816 (2013.01); G01S 7/4865 (2013.01); G01S 7/497 (2013.01); G01S 17/06 (2013.01); H01S 5/023 (2021.01); H01S 5/0233 (2021.01); H01S 5/0683 (2013.01); H01S 5/02257 (2021.01); H01S 5/0235 (2021.01); H01S 5/183 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A proximity sensor, comprising:
a light emitter configured to irradiate light to a target to be inspected;
a first light receiver having a first crosstalk characteristic, configured to detect an external reflected light from a target to be inspected within a first detection region;
a second light receiver having a second crosstalk characteristic different from the first crosstalk characteristic, configured to detect an external reflected light from a target to be inspected within a second detection region relatively further than the first detection region;
a structural member including a first light shielding wall, a second light shielding wall and a horizontal portion, wherein
the first light shielding wall, the second light shielding wall and the horizontal portion are integrally formed with one another,
the first light shielding wall extends vertically from the horizontal portion and is configured to shield an internal reflected light and an internal leaked light toward the second light receiver,
the second light shielding wall extends vertically from the horizontal portion and is configured to reduce an internal reflected light and an internal leaked light toward the first light receiver,
the horizontal portion is between a first chip on which the first light receiver is disposed and a second chip on which the second light receiver is disposed, and is between the second chip and a third chip on which the light emitter is disposed,
the first light shielding wall is disposed between the first light receiver and the second light receiver,
the second light shielding wall is disposed between the light emitter and the first light receiver,
the first light shielding wall, the second light shielding wall and the horizontal portion collectively surround the first chip,
the first, second and third chips contact the horizontal portion,
the first light receiver is surrounded by the first chip, and
the light emitter is surrounded by the third chip isolated from the first chip by the second light shielding wall.