What are the principles of microscopic imaging? Imaging principles of microscopy

In fact, ordinary optical microscopes are based on the imaging principle of convex lenses, and they need to go through two imaging of convex lenses. The first time is imaged through the objective lens (convex lens 1), the object should be between one and two times the focal length of the objective lens (convex lens 1), and according to the principles of physics, the real image should be magnified and inverted. Then, the first image of the object is used as the "object", and the second image is taken through the eyepiece.

Since we observe on the other side of the eyepiece, according to the principle of optics, the second image should be a virtual image, so that the image and the object are on the same side. Therefore, the image of the first time should be within one time of the focal length of the eyepiece (convex lens 2), so that after the second imaging, the image of the second image is an enlarged upright virtual image. If it is relative to the real thing, it should be an upside-down enlarged virtual image.

The working principle of the microscope is as follows:

1. Optical microscope.

An optical microscope mainly consists of an eyepiece, an objective lens, a stage, and a reflector. Both the eyepiece and the objective lens are convex lenses with different focal lengths. The focal length of the convex lens of the objective lens is smaller than that of the convex lens of the eyepiece.

The objective lens is equivalent to the lens of the projector, and the object passes through the objective lens into an inverted and magnified real image. The eyepiece is equivalent to an ordinary magnifying glass, and the real image is formed into an upright and magnified virtual image through the eyepiece.

2. Electron microscope.

Electron microscope is an instrument that replaces light beams and optical lenses with electron beams and electron lenses according to the principle of electron optics to image the fine structure of matter at very high magnification.

Microscopes: Optical microscopes and electron microscopes: The optical microscope was pioneered in 1590 by Janssen & Sons of the Netherlands. Now the optical microscope can magnify the object 1600 times, the minimum limit of resolution up to 1 2 wavelength, the length of the domestic microscope mechanical tube is generally 160 mm, which has made great contributions to the development of the microscope, microbiology for Leeuwenhoek, the Netherlands.

It's the same as a magnifying glass...

The microscope uses the magnification imaging principle of the convex lens to enlarge the tiny objects that the human eye can not distinguish to the size that the human eye can distinguish, which is mainly to increase the opening angle of the near tiny objects to the eye (objects with a large viewing angle are imaged on the retina), and use the angular magnification m to represent their magnification ability.

Since the angle of the same object to the eye is related to the distance of the object from the eye, it is generally stipulated that the magnification at a distance of 25 cm from the eye (photopic distance) is the magnification of the instrument. Microscopes usually have very small viewing angles when looking at objects, so the ratio of the angle of view can be replaced by the ratio of its tangent.

The microscope is one of the greatest inventions of the 20th century. Before its invention, human ideas about the world around us were limited to what the naked eye could see, or by using a hand-held lens to help the naked eye.

Microscopes have opened up a whole new world to human vision, and for the first time people have seen hundreds of "new" tiny animals and plants, as well as the inner workings of everything from the human body to plant fibers. Microscopes also help scientists discover new species and help doctors with diseases.

The first microscopes were made in the Netherlands in the late 16th century. The inventors were Yas Jensen, a Dutch optician, or another Dutch scientist, Hans Lipperch, who made a simple microscope out of two lenses, but did not make any significant observations with these instruments.

The microscope uses the magnifying imaging principle of a convex lens to magnify tiny objects that cannot be distinguished by the human eye to a size that the human eye can distinguish. The microscope needs to be imaged twice through a convex lens, and the first time the object is between one focal length and two times the focal length of the objective lens, forming an inverted magnified real image; According to the imaging law of the convex lens, it can be seen that the real image is located in the focal point or focus of the eyepiece, and is magnified again, forming an inverted magnified virtual image.

The first microscope was developed at the end of the 16th century by Jas Jensen of the Netherlands. The microscope is one of mankind's greatest inventions, and it has opened up a whole new world to mankind.