Lab Quiz 9/17

What part of the microscope is used to focus light on the specimen (slide)?

condenser

Magnification

the image would be larger/the factor by which an object's image appears larger than its actual size

the ability to distinguish detail

resolving power

resolving power is increased by

reducing the wavelength of light used

What two ways can be used to increase resolution of a microscope?

reducing wavelength of light used

increasing NA (numerical aperture) of objective lens

numerical aperture

unitless measurement of an optical system's ability to gather light and resolve fine details

What can one do to increase the contrast of a viewed specimen?

use of stains or dyes that bind to cellular structures and absorb light to provide contrast

What happens to the field of view when magnification is increased?

FOV decreases, and the brightness of the field is reduced.

What happens to working distance when magnification is increased?

working distance also decreases as magnification is increased.

Name two ways in which the stereoscopic (dissecting) microscope differs from the Light (compound) microscope.

Stereoscopic— it has two objective lenses for each magnification, can be observed in three dimensions, resolution + magnification less eff. bc of alignment

Light microscope

Uses white light, magnifying lenses, eyepieces to examine objects too small to observe with the naked eye

Contrast

is based on the differential absorption of light by parts of the specimen

field of view

the portion of the specimen which is observed

working distance

the distance between the specimen and the objective lens