2.1 (2.1.1) Microscopy

maximum magnification of a light microscope

x1500

maximum magnification of an electron microscope

x500000

resolving power of a light microscope

200nm

resolving power of TEM

0.5nm

resolving power of SEM

3-10nm

differences between SEM and TEM

SEM creates a 3D image by detecting deflected electrons whereas TEM creates a 2D image by transmitting electrons through a specimen

formula for calculating magnification

magnification= image/actual

how does a laser scanning confocal microscope work

a single spot of focused light moves across a specimen. this causes fluorescence from the components labelled with a dye. the emitted light from the specimen is filtered through a pinhole aperture. only light radiated from very close to the focal plane is detected

what is laser scanning confocal microscopy used for and why

used in diagnostic procedures of the eye as it is non-invasive. endoscopic procedures. drug development

future uses of laser scanning confocal microscopy

virtual biopsies especially for skin cancer