Explanation of the difference between laser confocal microscope and scanning electron microscope
Laser confocal microscope and scanning electron microscope are both point-source scanning imaging, and the magnification is adjusted by controlling the scanning driving range. Laser confocal microscope works by laser scanning and can obtain three-dimensional images. Scanning electron microscope (SEM) uses various physical signals excited by fine-focused electron beam scanning on the sample surface to modulate imaging, and only two-dimensional images can be obtained, but not three-dimensional images.
1. Different limit resolutions (different amplification signal sources)
Laser confocal: the limit resolution is 150nm.
Scanning electron microscope: 20nm~0.8nm
2. Different scanning driving modes.
Laser confocal: the laser rotating mirror controls the laser scanning range and scanning speed.
Scanning electron microscope: electromagnetic coil controls the scanning range and scanning speed of electron beam.
3. Stereo imaging is different
Laser confocal: the sample is imaged layer by layer in the Z-axis direction by a nano-precision stepping motor, and the software synthesizes the set images of each layer into a clear three-dimensional image.
Scanning electron microscope (SEM): Single-frame image has great depth of field and belongs to two-dimensional image.
4, the application scope is different
Laser confocal: several times to several thousand times
Scanning electron microscope: several times to several hundred thousand times
5. Different working environment
Laser confocal: It can test samples in atmospheric environment.
Scanning electron microscope: test samples in high vacuum environment.
