- #1

JulioHC

- 15

- 1

Good evening,

In the following weeks, I will be performing a lab project during three sessions and one of the things that I have to do is to create a microscope using a set of lenses (We are using a 50mm focal length convergent lens as the objective and a 100m focal length convergent lens as the eyepiece). In the last lab session we used to convergent lenses to create a microscope but without taking any readings, now at home I have done some research about microscopes and I have drawn some ray diagrams, I have also derived an equation to calculate the magnification of the system given the two focal lengths, the distance between lenses and the distance from the object to the first lens. The expression that I got is

$$\frac{f_{1}f_{2}}{(s_{1}-f_{1})(d-s_{1}^{'}-f_{2})}$$

Where

- ##f_{1},f_{2}## are the focal lengths of the objective and the eyepiece respectively.

-##s_{1}## is the distance from the object to the objective.

-##s_{1}^{'}## is the distance from the objective to the image it creates, which will then be used by the eyepiece to create the final image.

Using these and an online optics simulator I concluded that

- If the lenses are placed so that ##f_{2}## is located to the right of ##f_{1}##, the image is smaller than the object.

- If the lenses are placed so that ##f_{2}## and ##f_{1}## are at the same place then the magnification is equal to ##\frac{f_{2}}{f_{1}}## no matter where you place the object.

- If the lenses are placed so that ##f_{2}## is to the right of ##f_{1}## the magnification keeps increasing but the image is formed further from the eye piece. My thinking here is that although the magnification increases because the image keeps getting further it must be blurred or not more magnified but I will test this in the lab. Every ray diagram that I have seen on internet shows ##f_{2}## and ##f_{1}## coincident so I assume that ##\frac{f_{2}}{f_{1}}## might be the maximum possible magnification.

Now my question, as I want to test all these conclusions in the lab session I need to figure out a way of measuring experimentally the magnification of the microscope. However, I can't think of any way of doing it given that I can't project the image formed by the microscope as it is virtual. I have been searching online for some procedure to do it but I haven't found anything. That's why I wanted to ask you if you could provide me some help on this matter.

In the following weeks, I will be performing a lab project during three sessions and one of the things that I have to do is to create a microscope using a set of lenses (We are using a 50mm focal length convergent lens as the objective and a 100m focal length convergent lens as the eyepiece). In the last lab session we used to convergent lenses to create a microscope but without taking any readings, now at home I have done some research about microscopes and I have drawn some ray diagrams, I have also derived an equation to calculate the magnification of the system given the two focal lengths, the distance between lenses and the distance from the object to the first lens. The expression that I got is

$$\frac{f_{1}f_{2}}{(s_{1}-f_{1})(d-s_{1}^{'}-f_{2})}$$

Where

- ##f_{1},f_{2}## are the focal lengths of the objective and the eyepiece respectively.

-##s_{1}## is the distance from the object to the objective.

-##s_{1}^{'}## is the distance from the objective to the image it creates, which will then be used by the eyepiece to create the final image.

Using these and an online optics simulator I concluded that

- If the lenses are placed so that ##f_{2}## is located to the right of ##f_{1}##, the image is smaller than the object.

- If the lenses are placed so that ##f_{2}## and ##f_{1}## are at the same place then the magnification is equal to ##\frac{f_{2}}{f_{1}}## no matter where you place the object.

- If the lenses are placed so that ##f_{2}## is to the right of ##f_{1}## the magnification keeps increasing but the image is formed further from the eye piece. My thinking here is that although the magnification increases because the image keeps getting further it must be blurred or not more magnified but I will test this in the lab. Every ray diagram that I have seen on internet shows ##f_{2}## and ##f_{1}## coincident so I assume that ##\frac{f_{2}}{f_{1}}## might be the maximum possible magnification.

Now my question, as I want to test all these conclusions in the lab session I need to figure out a way of measuring experimentally the magnification of the microscope. However, I can't think of any way of doing it given that I can't project the image formed by the microscope as it is virtual. I have been searching online for some procedure to do it but I haven't found anything. That's why I wanted to ask you if you could provide me some help on this matter.