Contrast – requires light pass through a sample. Often cells are too clear.
Add dyes, or contrast, to the cell to enhance features. Works well in light and fluorescent microscopy, but often this requires the cells to be fixed and will not be able to observe movement/behavior or cells to the signals.
N = refractive index. Oil is about 1.5 and the larger it is, the better the resolution. The SMALLER the resolution, the closer two points can be a still be distinct structures.
Bestlambda is 450, oil 1.5, and angular is 70 degrees. = 194 nm. This means that two objects that are 200nm apart can be seen as distinct objects. If they are closer than this, they will not be seen as distinct structures.
Lambda – wavelength. This sets the limit on how an object can be and be seen by particular microscope. Smaller the wavelength, the smaller the object that can be seen.
Insertion of nomarski optic - A prism that splits light into two separate waves through specimen. Changes wavelength of light and the interference leads to increased contrast, largest difference is the edges of cells and organelles.
Takes advantage of physics of light and the characteristics of it as a waveform. When two waves are in phase, they are at the same frequ and combine to create a better resolution. If out of phase, reduced intensity of light. When inphase, the unstained cell will disrupt one of the light waves creating a slowed speed for the wave form.