From Biotechnology Procedures and Experiments Handbook

THE MICROSCOPY

Introduction

The microscope has been a valuable tool in the development of scientific theory and study of cells, microbes, etc, there are various types of microscopes available depending upon their use and functionality. A compound microscope is composed of 2 elements; a primary magnifying lens and a secondary lens system. Light passes through an object and is then focused by the primary and secondary lens. If the beam of light is replaced by an electron beam, the microscope becomes a transmission electron microscope. If light is bounced off of the object instead of passing through, the light microscope becomes a dissecting scope. If electrons are bounced off of the object in a scanned pattern, the instrument becomes a scanning electron microscope.

The function of any microscope is to enhance resolution. The microscope is used to create an enlarged view of an object so that we can observe details not otherwise possible with the human eye. Because of the enlargement, resolution is often confused with magnification, which refers to the size of an image. In general, the greater the magnification, the greater the resolution, but this is not always true. There are several practical limitations of lens design that can result in increased magnification without increased resolution.

If an image of a cell is magnified from 10X to 45X, the image gets larger, but not necessarily any clearer. The image on the left is magnified with no increase in resolution. The image on the right is magnified...

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Products & Services
Specialty Microscopes
Specialty microscopes are designed for specific applications such as metallurgy or gemology. They use specialized techniques or technologies such as acoustics to produce magnification.
Microscope Lenses and Objectives
Microscope lenses and microscope objectives include eyepieces or oculars, optical filters, objectives, adapters or mounts, condensers and other optical components for microscopy.
Scanning Probe Microscopes
Scanning Probe Microscopes forms images of surfaces by using a physical probe that scans the specimen. Examples include AFM (atomic force microscopes), MFM (magetic force microscopes), STM (scanning tunneling microscopes) and many others.
Measuring Microscopes
Measuring microscopes are used by toolmakers for measuring the properties of tools.  These microscopes are often used for dimensional measurement with lower magnifying powers to allow for brighter, sharper images combined with a wide field of view.

Topics of Interest

EXERCISE 1. THE BRIGHT FIELD MICROSCOPE Materials Binocular microscope Microscope slide Procedure Pick up a microscope from the cabinet by placing one hand under the base and the other on the arm of...

3.5 TEM Imaging System The imaging lenses of a TEM produce a magnified image or an electron-diffraction pattern of the specimen on a viewing screen or camera system. The spatial resolution of the...

EXERCISE 3. CELL SIZE MEASUREMENTS: OCULAR AND STAGE MICROMETERS Figure 11: Micrometery. Materials Microscope Ocular micrometer Stage micrometer Millimeter ruler Prepared slide Procedure Place...

2.8 Magnifiers and Microscopes The magnification of a microscope or a magnifier is, like that of a telescope, defined as the ratio of the angle subtended by the image to the angle subtended by the...

Overview As we saw in Chapter 1, the TEM is capable of displaying magnified images of a thin specimen, typically with a magnification in the range 10 3 to 10 6. In addition, the instrument can be...