公开(公告)号：US20230333014A1

公开(公告)日：2023-10-19

申请号：US18182010

申请日：2023-03-10

Applicant: Melexis Technologies NV

Inventor： Jos RENNIES ,  Luc BUYDENS

IPC: G01N21/55

CPC classification number: G01N21/55 ,  G01N2201/123 ,  G01N2201/12746

Abstract: In a heating appliance comprising a substrate for receiving an item of cookware, a method of measuring reflectivity comprises emitting a time-varying electromagnetic signal from a first side of the substrate, a portion of the time-varying electromagnetic signal propagating through the substrate. Electromagnetic radiation is then received at the first side of the substrate, the received electromagnetic radiation comprising a background ambient component received and a component reflected by the substrate. A gain factor is applied to translate the received electromagnetic radiation to a receive electrical signal. An offset signal component is then identified from the receive electrical signal, the offset signal component arising from the background ambient component of the received electromagnetic radiation. The gain factor from the offset signal component is then estimated using a characterisation of the offset signal component, and the reflectivity is calculated using the receive electrical signal and the estimated gain factor.

公开(公告)号：US20220187135A1

公开(公告)日：2022-06-16

申请号：US17512776

申请日：2021-10-28

Applicant: Melexis Technologies NV

Inventor： Jos RENNIES ,  Wouter REUSEN ,  Luc BUYDENS

IPC: G01J5/10 ,  H04N5/33 ,  H04N5/369 ,  H04N5/347

Abstract: A thermal imaging apparatus comprising: a thermal detector device (100) comprising an array of thermal sensing pixels (102) and signal processing circuitry (104) coupled to the detector device (100). The circuitry (104) supports a background identifier (110) and a pixel classifier (112), the background identifier (110) comprising a common intensity identifier (114) and an expected background intensity calculator (116). The background identifier (110) receives pixel measurement data captured by the detector device (100) in respect of pixels of the array (102) and the common intensity identifier (114) identifies a largest number of substantially the same pixel intensity values from the pixel measurement data. The expected background intensity calculator (116) uses the largest number of substantially the same pixel intensity values to generate a model of expected background intensity levels. The pixel classifier (112) uses the model to determine whether an intensity measurement by a pixel (118) of the array (102) corresponds to a background or an object in an image.