The figure below shows the optical paths of the two closely spaced light waves a
ID: 1794308 • Letter: T
Question
The figure below shows the optical paths of the two closely spaced light waves at different scanning locations in the sample, from left to right: both waves passing through water; one wave passing through water and the other through the cell; both passing through the cell. After passing through the sample chamber, the two waves of light are recombined in the DIC microscope. How the resulting “recombined" wave appears depends on whether the two waves are in phase (crests and troughs of both overlapping), completely out of phase (crests of one overlapping troughs of the other), or somewhere in between. DIO Question 4: How many wavelengths of light fit into a cell of length Az? Write your answer N in terms of the wavelength of the light (Ao in air) and the cell's refractive index n.Explanation / Answer
given
cell length = dz
then
wavelength of light in this medium = lambda/n
where n is refractive index of the cell
so wavelengths fitting the medium = dz*n/lambda
number of wavelengths fitting the cell of width dz and refractive index n , N = n*dz/lambdao