Forensics 2A Microscope

What is part A

objectives

What is part B

stage clips

What is part C

stage

What is part D

light source

What is part E

base

What is part F

eye piece

What is part G

arm

What part is H

diaphragm

What part is I

Coarse Adjustment Knob

What part is J

Fine Adjustment Knob

What does the arm do?

Supports the objectives

What does the diaphragm do?

Controls the amount of light being passed up toward the eyepiece 

What does the base do?

Supports the microscope

What does the eyepiece do?

To see an image close up

What do the stage clips do?

Holds the object in place

What does the stage do?

Supports the slide being observed, lowest position when using/put it away

What does objective lenses do?

Provide magnification, (scanning shortest, high power highest) hear the click. scanning->low->high

What does the Coarse adjustment knob do?

Moves the stage and focuses the image, only use in scanning power (smallest objective lense)

What does fine adjustment knob do?

Sharply focuses the image, “fine tune” the image you already have in focus, smaller knob

how to get total magnification?

eyepiece x objective

10 × 4 = 40x

20 × 40 = 800x

what is the lowest objective lense and the total magnification?

scanning power

10 × 4 = 40x

what is the middle objective lenses and the total magnification?

low power

10 × 10 = 100x

what is the most powerful objective lense and the total magnification?

high power

10 × 40 = 400x

Which adjustment focus knob do you ONLY USE in scanning power?

Coarse Adjustment Knob moves the stage and because you could crack the lense or the glass cover slip

When might you need to adjust the diaphragm?

To let more or less light in through the eyepiece

What should you do if you look through the eye piece and see all black?

Make sure Microscope is plugged in, make sure light is on, make sure the objective lense is clicked into place

Why must the specimen be centered before switching powers?

you won’t be able to see the speimen since it won’t be in the field of view

Why does sample size change?

as magnification increases field of view decreases