Microscope Flashcards

Flashcards about the compound light microscope and its parts.

Base

Where the microscope rests; serves as support for the whole microscope

Arm

Where the upper part of the microscope rests; where it is held.

Eyepiece

Where the user views the magnified image of the specimen; magnifies the image.

Objective lenses

Determines the amount of magnification.

Adjustment knobs

Allows user to move either the body tube or stage. This focuses the specimen to observe the contrast of details with the specimen to the background.

Mirror/Lamp

Light source.

Condenser

Focuses the light on the specimen; prevents scattering of light in the environment.

Iris diaphragm

Regulates the light that passes through the aperture and helps to adjust the brightness and contrast of the specimen.

40x / 0.65

Magnification / Numerical Aperture

Scanning Objective magnification

4x

LPO (Low Power Objective) magnification and NA

10x and 0.25

HPO (High Power Objective)

40x

OIO (Oil Immersion Objective)

100x

Total linear magnification

eyepiece magnification ✕ objective lens magnification

Numerical Aperture

Denotes resolving power of an objective.

Stage micrometer

slide with a scale with known values

Eyepiece micrometer

possess a graduated scale with no inherent value

proper handling of microscope

Hold the microscope with one hand by the arm and another supporting the base

Enumerate things that the microscope should be at upon receiving/returning

1. Stage should be at the lowest point

2. Objective lenses should be set to the lowest objective

3. Cord should be wrapped around the pillar

how does the viewed object move in relation to the movement of the slide

viewed object is flipped upside down and backwardsin relation to the slide movement.

what happens to contrast of image as the diaphram is closed

The contrast of the image increases as the diaphragm is closed, allowing less light to pass through and highlighting the details of the specimen.

for stained slides, diaphram should be

open to allow more light

for low contrast samples, diaphram should be

closed to reduce light —> better contrast

area ____ when changing from LPO to HPO

becomes smaller

total linear magnification

the product of the magnification of the eyepiece and the magnification of the objective lens used.

total linear magnification is denoted by

SOME VALUE X

numerical aperture

denotes the resolving power of an objective

the ability of the lens to gather light

higher NA higher brightness higher resolution

magnification of drawing is equal to __ and is denoted by

size of drawing / size of specimen

x SOME VALUE

how to calibrate eyepiece micrometer

1. align the two scales such that one line coincides with another

2. compute the calibration constant c =( #SMD / #EMD )x 10 mu m / mm

3. repeat for each objective lens

length of specimen

l = #EMD x c