Patent classifications
G
PHYSICS
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G01
MEASURING; TESTING
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G01N
INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
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21/00
Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
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G01N21/17
Systems in which incident light is modified in accordance with the properties of the material investigated
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G01N21/47
Scattering, i.e. diffuse reflection
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G01N2021/4733
Discriminating different types of scatterers
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G01N2021/4733

Dust sensor
12584856 · 2026-03-24 · ·

A dust sensor includes a photo detector configured to detect light scattered from dust; and a signal processing circuit having a high-pass filter receiving an electric signal generated from output of the photo detector. The signal processing circuit generates a dust detection signal using a signal provided to the high-pass filter as well as a signal output from the high-pass filter.