The main components and functions of laser confocal microscope
1. Illumination pinhole
Function: Make the laser light pass through the lighting pinhole to form a point light source. The point light source has unique advantages such as strong light source direction, small divergence, high brightness, high spatial and temporal coherence, and plane polarization excitation. And it forms a confocal device with the detector pinhole and the focal plane.
2. Beam splitter
Function: Separate sample-excited fluorescence from other non-signal light.
3. Objective lens
4. Focal plane
Function: The laser point light source irradiates the object and focuses on the focal plane, and excites the fluorescently marked sample to emit fluorescence to form a focal spot. The light spot is processed by a series of devices such as the objective lens and the beam splitter, and is focused on the illumination pinhole and the detector pinhole respectively. This is where the meaning of confocal comes from.
5. Detector pinhole
Function: Play the role of spatial filter. The scattered light on the non-focus plane and the scattered light outside the non-focus spot on the focus plane are hindered to the greatest extent, so as to ensure that all the fluorescence signals received by the detector pinhole come from the focus position of the sample spot, so the diffraction and collection of light spots on the sample and the detection The pinhole imaging spot of the detector contains the same information (two-point conjugate).
6. Photomultiplier tube (detector)
Function: Accept the light signal passing through the pinhole, convert it into an electrical signal and transmit it to the computer, and a clear image of the entire focal plane will appear on the screen.
7. Lasers: The development of confocal microscopy technology is inseparable from the rapid development of lasers. We can choose different lasers according to research needs. Such as ArUV (351.364nm), HeCd (442nm), AR (457,488,514nm), ArKr (488,568,647nm) Kr (568nm), HeNe (543nm), HeNe (633nm) and so on.
8. Multi-fluorescence channel: It has multiple fluorescence channels to realize multiple labeling of samples at the same time.
