An electronic device for detecting and classifying a defect of a wafer and a method of detecting and classifying a defect of a wafer are provided. The method includes obtaining an image of a wafer, dividing the image into a plurality of patches and extracting first features from the plurality of patches, selecting a target feature group from a plurality of feature groups, based on the first features, determining whether a defect exists in the wafer, based on the target feature group and the first features, and when the defect exists in the wafer, determining a defect type of the defect, wherein the plurality of feature groups is obtained through clustering based on second features extracted from a plurality of normal images.

In some examples, a method includes transmitting first light pulses according to a pre-determined pulse pattern in a first measurement period. The method also includes transmitting second light pulses according to the pre-determined pulse pattern in a second measurement period consecutive to the first measurement period, in which at least some of the first and second light pulses being unequally spaced in time across the first and second measurement periods. The method also includes receiving first detection signals representing detection of the first light pulses. The method also includes receiving second detection signals representing detection of the second light pulses. The method also includes providing a first light scattering measurement signal representing the first measurement period responsive to the first detection signals. The method also includes providing a second light scattering measurement signal representing the second measurement period responsive to the second detection signals.

A well counting device comprises an image acquisition unit that acquires one or more images of a plurality of wells capturing a target substance; and a counting unit that counts the number of wells emitting fluorescence among the plurality of wells for each of the one or more images acquired by the image acquisition unit, wherein the counting unit counts the number of wells emitting fluorescence, excluding a well that also emits fluorescence in adjacent wells, among the plurality of wells.

Method is presented for monitoring time-varying fluorescence. The method includes providing a measurement data set, transforming each Flr signal of each measurement data entry of the measurement data set to an agent intrinsic fluorescent (IF) signal, monitoring the agent IF signal for each measurement data entry within the measurement data set, whereby fluorescence emission of the agent is determined with reduced sensitivity to the time-varying optical properties of the medium.