US 12,203,838 B2
Smoke detector having light source surrounded by wall with varied heights
Yen-Chang Chu, Hsin-Chu County (TW); Cheng-Nan Tsai, Hsin-Chu County (TW); and Chih-Ming Sun, Hsin-Chu County (TW)
Assigned to PIXART IMAGING INC., Hsin-Chu County (TW)
Filed by PixArt Imaging Inc., Hsin-Chu County (TW)
Filed on Jan. 11, 2024, as Appl. No. 18/409,848.
Application 18/409,848 is a continuation of application No. 17/740,392, filed on May 10, 2022, granted, now 11,913,864.
Application 17/740,392 is a continuation in part of application No. 17/320,222, filed on May 14, 2021, granted, now 11,615,684.
Claims priority of provisional application 63/117,479, filed on Nov. 24, 2020.
Prior Publication US 2024/0142361 A1, May 2, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. G01N 15/06 (2024.01); G08B 17/107 (2006.01); G08B 29/18 (2006.01); G01N 15/00 (2006.01); G01N 15/075 (2024.01)
CPC G01N 15/06 (2013.01) [G08B 17/107 (2013.01); G08B 29/18 (2013.01); G01N 2015/0046 (2013.01); G01N 15/075 (2024.01)] 20 Claims
OG exemplary drawing
 
1. A smoke detector, comprising:
a substrate;
a light source, arranged on an upper surface of the substrate;
a light sensor, arranged on the upper surface of the substrate; and
a ring wall, arranged on the upper surface of the substrate and surrounding the light source, wherein a first part of the ring wall farther from the light sensor has a height more than that of a second part of the ring wall closer to the light sensor.