China Microscope - Wang Liang: 010-82967128 13910386343 The basic optical principle of the microscope

The basic optical principle of a microscope revolves around the behavior of light as it interacts with transparent media and lenses. Light travels in straight lines through uniform, isotropic materials, but when it encounters objects made of different densities, such as glass, refraction occurs. This happens because light moves at different speeds in different mediums. When light strikes a surface at an angle (not perpendicular), it bends, creating a refracted ray that forms a specific angle with the normal to the surface. Lenses are central to microscopes and are designed to manipulate light for magnification. There are two main types: convex (positive) lenses, which converge light, and concave (negative) lenses, which diverge it. Convex lenses focus parallel light rays to a point called the focal point, while concave lenses produce virtual images. The focal plane is the area where these focused rays intersect or appear to originate. Convex lenses follow five key imaging rules depending on the object's position relative to the focal points. For example, when an object is placed beyond the focal length, a real, inverted image is formed. If the object is at twice the focal length, the image is the same size. When the object is between the focal point and twice the focal length, an enlarged, inverted image is created. At the focal point itself, no image is formed, and if the object is inside the focal length, an erect, virtual image is produced. In terms of human vision, the eye can only distinguish details if the viewing angle is above a certain threshold. Without instruments, this angle is about 1 minute of arc. To observe smaller details, magnifying devices like magnifying glasses or microscopes are used. A magnifying glass creates a virtual image by placing the object within its focal length, and its magnification power depends on the focal length of the lens. A typical optical microscope includes components such as the stage, illumination system, objective lens, eyepiece, and focusing mechanism. The stage holds the specimen, while the focusing knobs allow precise movement to bring the sample into sharp focus. The illumination system, often including a condenser, ensures even and sufficient lighting. The objective lens provides the first level of magnification, and the eyepiece further enlarges the image for the viewer. Objective lenses vary in magnification, typically ranging from 5x to 100x, and some use immersion oil to enhance resolution. Eyepieces usually offer 5x to 20x magnification and come in different field-of-view options. Proper alignment and adjustment of the condenser and aperture diaphragm are crucial for optimal image quality. The resolving power of a microscope is limited by its numerical aperture and the wavelength of light. Excessive magnification without adequate resolution leads to blurry, uninformative images. Therefore, matching the numerical aperture with the total magnification ensures the best possible performance. Illumination techniques, such as bright-field or dark-field, also influence how details are observed, making them essential for different applications.

Aliphatic Polycarbonates APC

A polymer whose molecular backbone contains aliphatic esters. In other words, the parent nucleus R of the dihydroxyl compound HO -- R -- OH is polycarbonate of aliphatic group (CH2) M, (CH2)O(CH2), -- CH2 -- C(CH3)2 -- CH2 -- etc. It is characterized by low melting temperature, mostly below 60℃, and narrow melting range, greater solubility, low mechanical strength, hydrophilic, poor thermal stability, low glass transition temperature. Most aliphatic polycarbonate have low molecular weight and are mostly viscous liquid at room temperature or microcrystalline substance at low melting temperature. It can be prepared from aliphatic dihydroxyl compounds with dicarbonate or photogasification. Most of them have little industrial value, so their application is very limited.

Aliphatic Polycarbonates Apc,Rigid Bioplastics Aliphatic Polycarbonates Apc,Adhesives Aliphatic Polycarbonates Apc,Binders Aliphatic Polycarbonates Apc

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