
The device and the main parts of an optical microscope
Unlike a magnifying glass, a microscope has at least two stages of magnification. Functional and structural-technological parts of the microscope are designed to ensure the operation of the microscope and obtain a stable, most accurate, enlarged image of the object. Here we look at the structure of the microscope and try to describe the main parts of the microscope.
Functionally, the microscope device is divided into 3 parts:
Lighting part
Designed to create a luminous flux that allows you to illuminate the object so that the subsequent parts of the microscope perform their functions very accurately. The illuminating part of the transmitted light microscope is located behind the object under the lens in direct microscopes (for example, biological , polarization , etc.) and in front of the object above the lens in inverted . More about the types of light microscopes .
The illuminating part of the microscope design includes a light source (lamp and electric power supply) and an optical-mechanical system (collector, condenser, field and aperture adjustable / iris diaphragms).
The reproducing part
It is intended for reproducing an object in the image plane with the image quality and magnification required for research (i.e., for constructing such an image that would reproduce the object with the appropriate microscope optics resolution, magnification, contrast and color reproduction as accurately as possible).
The reproducing part provides the first stage of magnification and is located after the object to the image plane of the microscope.
The reproducing part includes a lens and an intermediate optical system.
Modern microscopes of the latest generation are based on optical systems of lenses adjusted to infinity. This additionally requires the use of so-called tube systems, which parallel light beams coming out of the lens “collect” in the image plane of the microscope.
The visualizing part
Designed to obtain a real image of the object on the retina, film or plate, on the screen of a television or computer monitor with additional magnification (second stage of magnification).
The imaging part is located between the image plane of the lens and the eyes of the observer ( digital camera ).
The visualizing part includes a monocular, binocular or trinocular visual nozzle with an observing system (eyepieces that work like a magnifying glass).
In addition, additional magnification systems (wholesale / change magnification systems) belong to this part; projection nozzles, including discussion ones for two or more observers; drawing machines; systems for analyzing and documenting images with appropriate adapters for digital cameras.
The mechanical part of the microscope
The microscope device includes a tripod, which is the main structural and mechanical unit of the microscope. The tripod includes the following main units: base and tube holder .
The base is a block on which the entire microscope is attached and is one of the main parts of the microscope. In simple microscopes, light mirrors or overhead illuminators are mounted on the base. In more complex models, the lighting system is built into the base without or with a power supply. Kindly visit this link for useful reference: parts of a compound microscope
Varieties of the base of the microscope:
- base with a lighting mirror;
- the so-called "critical" or simplified lighting;
- Koehler lighting.
The tube holder is a block, part of the microscope design , on which are fixed:
- a lens change unit having the following versions - a revolving device, a threaded device for screwing in the lens, a “slide” for threadless mounting of lenses using special guides;
- the focusing mechanism of rough and fine tuning the microscope for sharpness - the mechanism of focusing movement of lenses or tables;
- attachment point for removable subject tables;
- mounting unit for focusing and centering movement of the condenser;
- attachment point for interchangeable nozzles (visual, photographic, television, various transmitting devices).
Microscopes can use racks for attaching nodes (for example, a focusing mechanism in stereo microscopes or attaching a illuminator in some models of inverted microscopes).
A purely mechanical node of the microscope is a stage designed for fastening or fixing in a certain position of the object of observation. Tables are fixed, coordinate and rotating (centered and non-centered).
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