Microscopes

Microscope - uses and areas of application in laboratory

Microscopes are used above all in laboratories in the fields of science, research, development, industry and production. A microscope is an essential piece of laboratory equipment in biology, medicine, chemistry or material sciences. For example, our microscopes are used in industrial, biological and medical laboratories for the examination of tissue and cell cultures, urine, blood, plasma, smears, microorganisms, bacteria, yeasts, fungi, mycoses or histological sections. The areas of application of the available microscopes by Kern & Sohn, Helmut Hund, A. Krüss Optronic or Levenhuk include hospitals, medical practices, research institutions, universities, specialist colleges and schools. Our cost-effective microscopes are suitable for professional use in cell and microbiology, in veterinary and human medicine, such as in dermatology, urology, gynaecology or pathology, and they are also used for the production of food and drinks in the food industry and breweries, as well as for the analysis of wastewater samples and slurry in treatment plants. In industrial production, microscopes are also used for materials examination and work materials testing. We are happy to advise you in selecting the most suitable microscope for your laboratory. For this use our contact form or simply call us on: +49(0)3338 - 7510456.

Microscopes - function and structure of a microscope

A microscope is an optical instrument for the examination and enlarged viewing of very small objects. Fundamentally microscopes consist of two optical components, the objective lens and the eye-piece. These are connected to each other by the microscope tube. The different microscopes vary depending on their design and area of application. In accordance with their design, in our online shop we classify the laboratory microscopes into upright and inverted types.

Essentially the structure of a conventional microscope usually comprises the following microscope components:

• Eyepiece - into which you look, enlarges the intermediate image produced by the objective lens and projects it onto the retina of the eye;
• Tube - binocular, mainly oblique tube on the upper end of the microscope;
• Objective - located on the microscope above the object being viewed;
• Objective revolver - allows objective lenses to be rapidly changed;
• XY cross-table - movable mechanical stage for the precise positioning of the object to be viewed on the microscope stage.
• Stage - working plate with a hole in the centre, including sample clips;
• Condenser - a lens system on the microscope below the object stage, optical light collector which concentrates the light
• Condenser drive - buttons for focusing the illuminated and applied preparation;
• Lighting - a microscope lamp or a mirror mostly serve to illuminate the preparations;
• Field diaphragm - restricts the illuminated area to the object being observed
• Frame with coarse and fine focussing - usually two adjusting wheels for focussing;
• Microscope foot - baseplate of the microscope.

Microscope - types of microscope

In the online shop the microscopes on offer are sub-divided by microscope type, structure, objectives, illumination method and contrasting methods.

Microscope types: At present our range includes stereomicroscopes and monocular microscopes, binocular microscopes as well as trinocular microscopes. A stereomicroscope always has two eyepieces like every binocular microscope whereby in a stereomicroscope the image is always produced simultaneously by two objective lenses which depict the object from different viewing angles which ultimately results in the stereo effect. In a trinocular microscope the third eyepiece is usually used with an additional vertically projecting photo tube for attaching a camera.

Microscope objectives: Many properties of the microscope image depend on the selected microscope objective. We currently sub-divide these into achromatic, epiplan objective, planachromatic, planachromatic, infinity corrected and semi-planachromatic. Due to their simple mechanical and optical design, achromatic objectives, known as achromates, are usually the least expensive and most widely used objective lenses in microscopy. As a rule these microscopes comprise three lenses and are excellently suited for many routine microscopic examinations in the laboratory. The imaging errors of achromatic microscope objectives are not corrected as much as in the case of, say, planachromatic microscope objectives, which normally eliminate the image field curvature that occurs in a microscopic image and are richer in contrast.

Microscope lighting: In terms of microscope lighting we sub-divide the microscopes in the shop into incident light, incident fluorescence light and transmitted light. In contrast to transmitted light microscopes, in incident light microscopes the sample being viewed is not transilluminated. In an incident light microscope the sample is lit from the direction of the objective, often by the objective itself. Fluorescence microscopes utilise the physical effect of fluorescence for the microscopy of samples. Here, fluorescence dyes are stimulated with light of a certain wavelength and a few nanoseconds later light at another wavelength is emitted. Special filters ensure that only the emitted light is observed.

Microscopy contrast methods: With regard to the contrast method we differentiate between incident light fluorescence, incident light bright field, dark field, tranmitted light bright field and phase contrast. Many microscopic samples, such as living cells or bacteria, are almost transparent in the unstained state and can hardly be seen with a classic bright field microscope. Therefore there are different contrast methods in microscopy, such as with a dark image background (dark field) or the widely used method of phase contrasting for which special objective lenses and a condenser are required.

Microscopes and microscopy - accessories

In our microscope range we only carry high-quality microscopes by established manufacturers. The robust microscopy solutions are characterised by their reliable quality, high level of diagnostic certainty and service-life as well as the functional feature of being able to interchange microscope parts or add accessory sets. Depending on the model and manufacturer you can order various replacement parts and accessories for your microscope online, such as various objective lenses, attachments, filters, eyepieces, condensers, stands, stages, sample clips, camera adapters, lighting elements as well as many other accessories and components for the microscopes on offer.