US 11,686,875 B2
Stud finder employing photochromism
Jeremy Rubens, Palatine, IL (US); and Christopher Crowell, Chicago, IL (US)
Assigned to Robert Bosch Tool Corporation, Broadview, IL (US); and Robert Bosch GmbH, Stuttgart (DE)
Filed by Robert Bosch GmbH
Filed on Dec. 11, 2020, as Appl. No. 17/119,261.
Prior Publication US 2022/0187487 A1, Jun. 16, 2022
Int. Cl. G01R 19/00 (2006.01); G01V 3/08 (2006.01); F21V 9/08 (2018.01); G01V 3/165 (2006.01); G01R 27/26 (2006.01); G01V 3/15 (2006.01); F21Y 115/10 (2016.01); F21W 111/00 (2006.01); G01R 29/08 (2006.01); G01R 31/60 (2020.01); G01R 31/58 (2020.01)
CPC G01V 3/08 (2013.01) [F21V 9/08 (2013.01); G01R 27/2605 (2013.01); G01V 3/081 (2013.01); G01V 3/15 (2013.01); G01V 3/165 (2013.01); F21W 2111/00 (2013.01); F21Y 2115/10 (2016.08); G01R 29/085 (2013.01); G01R 31/58 (2020.01); G01R 31/60 (2020.01)] 11 Claims
OG exemplary drawing
 
1. A handheld stud finder system, comprising:
a housing having a surface configured to be placed proximate a substrate;
a stud-finding circuit disposed within the housing, the stud-finding circuit configured to locate an object behind the substrate;
an ultraviolet light source at least partially disposed within the housing, wherein the ultraviolet light source is configured to emit an ultraviolet light outward from the housing and towards the substrate;
a photochromic compound, configured to be applied to the substrate, wherein ultraviolet light causes the photochromic compound to change color; and
a control circuit in communication with the stud-finding circuit and ultraviolet light source, configured to activate the ultraviolet light source when the surface of the housing is slid over a location on the substrate behind which an object is located thereby illuminating a portion of the photochromic compound with the ultraviolet light causing the portion of the photochromic compound to change color,
wherein the changed color of the photochromic compound allows for the identification of a location on the substrate behind which an object is located based on the location of the portion of photochromatic compound that has changed color after the surface of the housing of the handheld stud finder is no longer proximate the substrate to where the object behind the substrate is located.