Main components and functions of laser confocal microscope
1. Illuminating pinhole
Function: The laser passes through the illumination pinhole to form a point light source. The point light source has unique advantages such as strong light source directionality, small divergence, high brightness, high spatial and temporal coherence, and plane polarization excitation. And form a confocal device with the detector pinhole and focal plane.
2. Beam splitter
Function: Separate sample excitation fluorescence from other non-signal light.
3.Objective lens
4.Focal plane
Function: The laser point light source illuminates the object and focuses it on the focal plane, stimulating the fluorescently labeled 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 beam splitter, and is focused at the illumination pinhole and the detector pinhole respectively. This is where the meaning of confocal comes from.
5. Detector pinhole
Function: Acts as a spatial filter. Maximize the obstruction of non-focused plane scattered light and scattered light outside the non-focused spot on the focusing plane to ensure that all fluorescence signals received by the detector pinhole come from the focus position of the sample spot, so the diffraction focused spot on the sample and detection The pinhole imaging spot contains the same information (two points conjugate).
6. Photomultiplier tube (detector)
Function: Receive the light signal passing through the pinhole, convert it into an electrical signal and transmit it to the computer, so that a clear image of the entire focal plane appears 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), etc.
8. Multiple fluorescence channels: It has multiple fluorescence channels to achieve multiple labeling of samples at the same time.
