Differential Interference Contrast microscopy(DIC)

For some days I’ve been thinking about this type of microscopy .I saw this on a video on the youtube channel called ‘journey to the microcosmos’,this video blew my mind ,then i remembered that i do have a foldscope,from then i’ve tried to think on how i can do this ,but it was worth the time . .This type of microscopy has special type of 3D effect which is most fascinating .This is mainly about some fascinating optics which I’ve done some research on the internet(Since I’m a physics lover).

HOW DOES DIC WORK?

Light emitted from the source is linearly polarised by passing through a polariser. The linearly polarised beam of light enters an objective-specific prism, which splits it into two rays that vibrate perpendicular to each other. The rays are parallel as they pass through a condenser, but as they are vibrating perpendicular to each other, they are unable to cause interference. 

The split beams pass through the specimen. The specimen’s varying thickness and refractive indices alter the wave paths of the beams. They then enter the objective, where they are focussed above the rear focal plane. The two beams enter a second prism, in the nosepiece, which combines them. Because the beams passed through different parts of the specimen, they have different lengths.

The analyser, which is a second polariser, brings the vibrations of the beams into the same plane and axis, causing destructive and constructive interference to occur between the two wavefronts. The light then travels to the eyepiece or camera, where a DIC image with differences in intensity and colour, can be seen. 

please think about this type of microscopy (anyone down in the comments) and how we implement this on foldscope ,this could be a change on how we think about the foldscope.

I’m also attaching the link of the video i’ve mentioned above, below

3 Comments Add yours

  1. jot:entdecken says:

    The polarizers are easy to find as films or sheets. They’re therefore not the problem. Is there maybe a way to achieve whatever the prism does with a component that is also available in film or sheet form?

    Than you could simly stack all components in the necessary order and voila – there is your DIC-Foldscope…

  2. Anik Khan says:

    i know but the prism would take up some space as there are two prisms which are placed above and below the sample ,that’s how the light interferes ,which would make the sample difficult to focus ,that prism even LOOKS costy. We need to think of some other way

  3. Manu Prakash says:

    Here is a tutorial to collect phase contrast data with a foldscope – technically this is an oblique angle illumination, but the visual effect is the same. The video also shows how to do both transmitted light, phase contrast and dark field – all with the same simple technique.

    https://microcosmos.foldscope.com/?p=16093

    This has a lot of content – and is backward compatible to foldscope v1 as well.

    Once you implement it; please do share videos here.

    Cheers
    Manu

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