# What is the field of view of a microscope at 400x?

**Field of view**is how much of your specimen or object you will be able to see through the

**microscope**. At

**40x**magnification you will be able to see 5mm. At 100x magnification you will be able to see 2mm. At 400x magnification you will be able to see 0.45mm, or 450 microns.

A.

### How do you calculate the field diameter of a microscope?

To

**calculate**the magnification, simply multiply the ocular lens (10x) by the objective lens. With this**microscope**you can obtain four different magnifications: 40x, 100x, 400x and 1000x. The original diameters of**field**of view (**fov**) were determined with a transparent mm ruler.#### How do you calculate the total magnification?

To figure the**total magnification**of an image that you are viewing through the microscope is really quite simple. To get the**total magnification**take the power of the objective (4X, 10X, 40x) and multiply by the power of the eyepiece, usually 10X.#### What is the field number of a microscope?

**Field number**is the diameter of the eyepiece lens and is most often expressed in millimeters.**Field**of View (FOV) is the amount of the object that can be seen with a particular optic combination (eyepieces + objective lens). It is the circular area that is seen when looking through the**microscope**.#### How do you calculate the size of a cell?

*To figure the length of one**cell**, divide the number of**cells**that cross the diameter of the field of view into the diameter of the field of view. For example, if the diameter of the field is 5 mm and you estimate that 50**cells**laid end to end would cross the diameter, then 5 mm/50**cells**= 0.1mm/**cell**.

B.

### What does diameter of the field mean?

In fiber optics, the mode

**field diameter**(MFD)**is**an expression of distribution of the irradiance, i.e., the optical power per unit area, across the end face of a single-mode fiber.#### What is the field of view of a microscope?

When you look through the lens of a**microscope**you see a circular area, the diameter of which is known as the**field of view**. To work out the**field of view**we need to know the**field**number and the magnification of the objective lens. So the image, when seen with the eyepiece only, has a diameter or 20 mm.#### How do you calculate the size of a cell?

*To figure the length of one**cell**, divide the number of**cells**that cross the diameter of the field of view into the diameter of the field of view. For example, if the diameter of the field is 5 mm and you estimate that 50**cells**laid end to end would cross the diameter, then 5 mm/50**cells**= 0.1mm/**cell**.#### How does the field of view change from low to high power?

Going to**high power**on a microscope decreases the area of the**field of view**. The**field of view**is inversely proportional to the magnification of the objective lens. The specimen appears larger with a higher magnification because a smaller area of the object is spread out to cover the**field of view**of your eye.

C.

### What is the total magnification at 4x 10x and 40x?

Objective Lenses: Usually you will find 3 or 4 objective lenses on a microscope. They almost always consist of 4x, 10x, 40x and

**100x**powers. When coupled with a 10x (most common) eyepiece lens, total magnification is 40x (4x times 10x),**100x**,**400x**and**1000x**.#### What is the total magnification of the microscope is on low power?

To figure the total magnification of an image that you are viewing through the microscope is really quite simple. To get the total magnification take the power of the objective (**4X**,**10X**,**40x**) and multiply by the power of the eyepiece, usually**10X**.#### What can you say about the relationship between magnification and field of view?

There is an**inverse**relationship between the total magnification and the diameter of the field of view – i.e., as magnifications**increases**the diameter of the field decreases in proportion, so the diameter of field of view at different magnification can be**calculated**mathematically, using the formula.#### What does an iris diaphragm do on a microscope?

**Iris Diaphragm**controls the amount of light reaching the specimen. It is located above the condenser and below the stage. Most high quality microscopes include an Abbe condenser with an**iris diaphragm**. Combined, they control both the focus and quantity of light applied to the specimen.

Updated: 2nd October 2019