Magnification in scanning electron microscope, Physics

Assignment Help:

How is magnification in scanning electron microscope controlled?

Magnification in scanning electron microscope:

Magnification into a SEM (scanning electron microscope) can be controlled over a range of regarding 5 orders of magnitude start from x25 or less to x 250,000 or more. Not like optical and transmission electron microscopes, representation magnification into the SEM (scanning electron microscope) is not a function of the power of the purpose lens. SEMs (scanning electron microscopes) may have objective and condenser lenses, but their purpose is to focus the beam to a spot, and not to illustrate the specimen. Given the electron gun can produce a beam with sufficiently small diameter, a SEM (scanning electron microscope) could in principle work fully without condenser or objective lenses, although this might not be extremely versatile or attain very high resolution. In an SEM, as in scanning probe microscopy, magnification results through the ratio of the dimensions of the raster onto the specimen and the raster onto the display device. Assuming which the display screen has a fixed size, higher magnification results by reducing the size of the raster onto the specimen, and vice versa. Therefore Magnification is controlled through the current supplied to the x,y scanning coils, and not through objective lens power.


Related Discussions:- Magnification in scanning electron microscope

Semiconductor materials: gallium arsenide, Energy gap: 1.4ev at room temper...

Energy gap: 1.4ev at room temperature Its charactistics are very closely related to those of germanium. This is under stable, since Gallium is the third column neighbour and a

Pendulum, a pendulum is timed ,first for 20 swings and then for 50 swings ;...

a pendulum is timed ,first for 20 swings and then for 50 swings ; time for 20 swings = 17.4 sec and time for 50 sec = 43.2. calculate the average time per swing/

Explain conservative force and non-conservative force, Conservative Force :...

Conservative Force : A force is told conservative when the work completed by the force in moving a particle from an instance to another instance is independent of the path followed

Find the electric flux, The elctric field in a certain region of space has ...

The elctric field in a certain region of space has components E x = 6.0 N/C, E y = 7.0 N/C, and E z = 0. Find the electric flux though the surface x = 6 y , 0 x

Explain angle of deviation, Angle of Deviation: When a ray of light pas...

Angle of Deviation: When a ray of light passes by a prism, It changes it's path inside the prism and forms an angle with the emergent ray. This angle is called as the angle of

Like and unlike pararell forces, what is the difference between like and un...

what is the difference between like and unlike pararell forces?

Find out the significancy, In the movie The Shooter starring Mark Wahlber...

In the movie The Shooter starring Mark Wahlberg, it is claimed that coriolis forces need to be taken into consideration when taking a shot at a target 4 kilometres away. To test

Types of light in order from lowest to highest frequency, Question Pu...

Question Put the different types of light in order from lowest frequency to highest frequency. Feedback: These are all instances of electromagnetic radiation. Elect

Radiography and depletion of ozone layer, Radiography and depletion of Ozon...

Radiography and depletion of Ozone layer: What is Radiography?  A. The method in which soft X-rays are used in medical diagnosis is called radiography. What are the uses

Newtons laws of motion, what is the concept behind solving question wedge b...

what is the concept behind solving question wedge block system if block i made to constrain . how to solve such question by using line of action of force

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd