In the use of microscope, the imaging quality is one of the most concerned issues for researchers and experimenters. The quality of microscope imaging is often influenced by many factors. Today, phenix Optics will take you to discuss the key factors that affect microscope imaging.
1. Optical factors
Optical system is the core part of microscope, and its design and manufacturing quality directly affect the imaging effect.
(1) Color difference
Chromatic aberration is a serious defect in lens imaging, which occurs when polychromatic light is used as the light source. White light is composed of many colors, and the refractive index of light with different wavelengths is different when it passes through the lens, which may cause a spot on the object side to form a color spot on the image side. Color difference can be divided into position color difference and magnification color difference. Position color difference makes the image have spots or halo rings, while magnification color difference makes the image have colored edges.
(2) spherical aberration
Spherical aberration is the monochromatic phase difference of points on the axis, which is caused by the spherical surface of the lens. Spherical aberration will make a point become a bright spot with bright middle and gradually blurred edge after imaging, thus affecting the imaging quality. The correction of spherical aberration is often eliminated by lens combination.
(3) Astigmatism
Astigmatism is the monochromatic phase difference of off-axis points. When the field of view is large, the object point on the edge is far from the optical axis, and the beam is tilted greatly, which causes astigmatism after passing through the lens. Astigmatism makes the original object point become two separated and perpendicular short lines after imaging, forming an oval spot.
(4) Field Curvature
Field curvature is also called "image field curvature". When there is field curvature in the lens, the intersection of the whole beam does not coincide with the ideal image point, and the whole image plane is a curved surface. This makes it impossible to see the whole face at the same time during microscopic examination, which makes it difficult to observe and take pictures. The objective lens of a research compound microscope is generally a flat-field objective lens, which has corrected the field curvature.
Second, the factors of microscope components
(1) microscope objective lens
The microscope objective lens can be divided into about 6-8 grades according to the grade, and the flat-field achromatic objective lens is commonly used. The grade of the objective lens directly affects the imaging quality. The lower the grade, the worse the imaging quality. Therefore, it is recommended to choose an objective lens with a level above the flat field.
(2) condenser
The aperture stop of the condenser should match the numerical aperture of the objective lens as much as possible to get the best image resolution.
(3) Focusing system
Focusing system is an important part of mechanical part, and focusing accuracy is very important. For beginners or operators who are new to the microscope, skilled use of the focusing system can quickly find and focus the image and improve work efficiency.
(4) stage
When observing slices, the stage often moves X and Y.. The double-layer mechanical moving platform has good accuracy and stability, and can provide good imaging quality when observing microscopic images.
Third, lighting factors
(1) Lighting system
The influence of illumination system on the imaging quality of professional microscope can not be ignored. Using the lighting device with low temperature and high color temperature, the resolution and sharpness of the observed microscopic image will be higher.
(2) Field of view diaphragm
The aperture of the field of view should be opened to a suitable position according to the observation of different objects and the magnification of the objective lens. If it is too large or too small, the brightness of the field of view of the microscopic image will be affected.
IV. Sample preparation factors
When using a microscope, the preparation of the detected object is very important. For example, whether the slice thickness is appropriate and whether the cover glass meets the national standard will affect the imaging quality.
V. Other factors
(1) Aspheric condenser
Aspheric condenser can provide very uniform illumination light, thus improving the contrast of microscopic images.
(2) Cora lighting system
Cora lighting system can adjust the optical central image. This system is used by scientific microscopes to provide high-quality micrographs for microscopic examination and professional digital microscopic imaging systems.
The improvement of microscope imaging quality needs to start from optical design, component selection, lighting conditions and sample preparation. As a professional brand in the optical field, phenix Optics has been committed to providing users with high-quality microscope products and helping researchers and experimenters to obtain clearer and more accurate microscopic images. If you have more questions about microscope imaging, please feel free to consult phenix Optics.
