Advantages of Confocal LaserMicroscopy
In practice, the vibration directions of the upper and lower polarising lenses of the polarising microscope should be orthogonal to each other, or in the east-west or north-south direction, and each should be in line with the cross wire of the eyepiece in the transverse and longitudinal directions. Sometimes only a lower polariser is used for observation, the vibration direction of the lower polariser must be determined, so the polariser must be corrected during operation.
1, eyepiece cross filament detection
To check whether the eyepiece cross filament is orthogonal, and whether it is consistent with the vibration direction of the upper and lower polarizers. At the same time, select a piece of black mica with complete resolution pole, move it to the centre of the eyepiece cross filament, place the resolution slit parallel to one of the cross filaments, write down the number of scales of the carrier table, then turn the animal table so that the resolution slit is parallel to the other cross filament, write down the number of scales of the carrier table, and the difference of two scales is 90°, which indicates that the cross filaments are orthogonal.
2,Determination and correction of the vibration direction of the lower polariser
Use black mica to check the vibration direction of the lower polarizer, because black mica is a widely distributed transparent mineral, which is very characteristic in single polarised light. First find a piece of solved and clear black mica, move it to the centre of the eyepiece cross filament, launch the upper polarizer, rotate the carrier table for one week, and observe the change of the colour of black mica, because the black mica absorbs the vibration light in the direction of solved * strong, so when the black mica colour reaches * deep, the direction of the solved slit is the vibration direction of the lower polarizer.
3,Correction of orthogonality of upper and lower polarizers
After the direction of the lower polarizer is corrected, remove the sheet and push it into the upper polarizer to observe whether the field of view is completely black, i.e. whether it is in an extinction state. If it is all black, it means that the vibration directions of the upper and lower polarisers are orthogonal to each other. Otherwise, the upper polariser must be corrected, i.e. rotate the upper polariser so that the field of view reaches * dark. When turning, the stop screw of the upper polariser must be loosened first, and then tightened after correction.
