Dilun transmission reflection polarizing microscopeIt is an advanced microscopic device that combines optical microscopy and polarization technology, which can use polarized light to observe and analyze samples with birefringence properties. The principle of polarized light produced by the reflection, refraction, birefringence, or scattering of light under specific conditions. When natural light passes through a polarizer, its vibration is restricted in a specific direction, forming polarized light. When this polarized light passes through the sample, if the sample has birefringence, it will split the light into two beams with different vibration directions. By analyzing the interference phenomena of these beams, the internal structure and optical properties of the sample can be revealed.
Dilun transmission reflection polarizing microscopeThe operation steps are as follows:
1. Power on and preparation
Connect the power supply, turn on the power switch of the polarizing microscope, and wait for the instrument to preheat for a period of time, usually about 5-10 minutes, to ensure stable light source and normal operation of all components of the instrument.
Check whether the objective lens and eyepiece are clean and tidy. If there is dirt, use specialized lens cleaning paper to gently wipe them.
According to the observation requirements, choose a suitable objective lens and install it on the objective converter. Usually, start observing from a low magnification objective lens, such as a 10 × objective lens.
2. Place the sample
For transmission observation: Place the prepared transparent or semi transparent sample on a glass slide on the stage, cover it with a cover glass, and ensure that the sample is flat and located in the center of the light hole on the stage.
For reflection observation: Place the opaque sample directly on the stage and fix it with a clamp or other fixing device, so that the observation surface is facing up and the surface is flat.
3. Adjust the lighting system
Transmission lighting: If conducting transmission observation, ensure that the brightness of the light source is moderate, which can be achieved by adjusting the brightness knob of the light source. At the same time, check whether the position of the spotlight is correct. Generally, by raising or lowering the spotlight or adjusting its focal length, the light can be evenly directed onto the sample to obtain a clear image.
Reflective lighting: When conducting reflective observation, it is necessary to adjust the reflective light path. Usually, the reflective lighting source, such as halogen lamps or LED lamps, is first turned on. Then, by adjusting the angle of the reflector or using the built-in reflective light path adjustment device, the light is accurately directed onto the surface of the sample and reflected back to the objective lens.
4. Observation and focusing
Open your eyes and observe the field of view through the eyepiece, while rotating the coarse focus screw to slowly raise or lower the stage until you see a blurry image of the sample.
Then, gently rotate the fine focus spiral to gradually make the image clearer. During the focusing process, the objective lens converter can be adjusted appropriately to try different magnifications of the objective lens for observation, in order to obtain clearer details or a broader field of view.
5. Polarization observation and analysis
If observing in polarized mode, it is necessary to insert the polarizer (lower polarizer) and analyzer (upper polarizer) into the optical path. Normally, the polarizer should be positioned at an appropriate azimuth angle, such as 0 ° or 90 °, depending on the characteristics of the sample and the purpose of observation.
Rotate the analyzer and observe the changes in the image. When the analyzer and polarizer are orthogonal (i.e. their vibration directions are perpendicular to each other), extinction occurs, and the image is darkest at this time; When the analyzer rotates parallel to the polarizer, the image is at its brightest. By observing the changes in brightness and the interference color and multi-color characteristics of the sample under polarization, the optical properties of the sample can be analyzed and identified.
It is also possible to change the orientation angle of the sample by rotating the stage, and further observe the changes in the optical properties of the sample in different directions, in order to obtain more information about the sample structure.
6. Photography and Recording
If it is necessary to take photos and record the observed images, a camera or camera device can be connected to the photography interface of the microscope. According to the device's instructions, set the shooting parameters such as exposure time, white balance, etc., and then press the shutter button to take a photo.
At the same time as recording the image, detailed observation conditions should also be recorded, including objective magnification, light source brightness, azimuth angles of polarizer and analyzer, sample information, etc., for reference in subsequent analysis and research of the image.
7. Shutdown and organization
After observation, first adjust the brightness of the light source to low, and then turn off the power switch.
Remove the sample, clean the stage and work area, turn the objective lens to a low magnification position, cover it with a dust cover, and properly store the microscope.