Page 612 - Ultimate Visual Dictionary (DK)

THE MODERN WORLD
High-performance

microscopes FEI TECNAI G TRANSMISSION
2
ELECTRON MICROSCOPE
Electron
gun
OPTICAL MICROSCOPES FORM A MAGNIFIED image by using housing
lenses to bend light. Some special-purpose optical microscopes
used in industry and research are designed for observing
particular materials, such as living cells. They produce
magnifications of up to about 2,000. Electron microscopes
produce magnifications of as much as 50 million, although
2 million is more typical. Their images are formed by means
of electrons focused by magnetic lenses. There are two main
types: scanning electron microscopes (SEMs) scan electrons
back and forth across the surface of a specimen; transmission
electron microscopes (TEMs) transmit electrons through a
thin slice of the specimen.
TEM IMAGE OF A VIRUS

Evacuated
Video camera column

Right Condenser
eyepiece aperture
Condenser
housing
Filter turret
OPTICAL MICROSCOPE IMAGE Objective
OF DYING NERVE CELLS lens and
Objective lens specimen
stage
Left eyepiece Manipulator
Objective
Manipulator aperture
Imaging system
housing
Vacuum valve

Detector

Specimen Binocular
eyepieces
Specimen
stage

Viewing screen
OLYMPUS BX51W1 OPTICAL MICROSCOPE

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