BIO 2271: Brightfield Microscopy

brightfield microscope

microscope that allows light rays to pass through a slide/specimen and then through various lenses to the eye

-the lenses magnify the object

how should you always transport a microscope?

using TWO hands. one on arm and one under base

What are the 3 lens systems of the microscope?

1.) oculars

2.)objective

3.)condenser

Oculars

these are the eye pieces. they = 10x and have two or more lenses

Objectives

-there are 4, which are attached to the nosepiece of the microscope

-scanning(red)= 4x

-low(yellow)= 10x

-high dry(blue)= 40x

-oil immersion(white)= 100x

total magnification formula

ocular magnification(10x) x objective magnification(4x, 10x, 40x, 100x)

condenser

under stage, collects and directs light

-diaphragm controls amount of light coming through

SHOULD ALWAYS BE IN ITS HIGHEST POSITION

resolution

ability to distinguish two points as separate objects

numerical aperture

measure of a lens' ability to capture light coming from a specimen and using it to make an image. increases with use of oil and higher objectives

numerical aperture for each objective

4x= 0.10

10x= 0.25

40x= 0.65

100x= 1.25