The embodiment of the invention provides an optical detection device which comprises an imaging
assembly and a photoelectric detection device, and the imaging
assembly is used for forming an image on an
image plane of a to-be-detected area of a
wafer. And the photoelectric detection device is used for receiving images and is arranged at the
image plane. The photoelectric detection device comprises a
light beam separation
assembly and a sensor assembly, the
light beam separation assembly is used for dividing a continuous
first light signal in an image into multiple beams of second light signals, and the
light beam separation assembly comprises a
microlens array. The sensor assembly is used for receiving multiple beams of second optical signals, and each pixel unit of each sensor in the sensor assembly is used for receiving one beam of second optical
signal in the multiple beams of second optical signals. The sensor assembly comprises a single-pixel sensor, and the single-pixel sensor corresponds to one micro lens in the
micro lens array; and / or, the sensor assembly comprises a multi-pixel sensor, the multi-pixel sensor corresponds to a plurality of microlenses in the
microlens array, and spatial segmentation is beneficial to improving the
signal-to-
noise ratio.