Comment by crispyambulance

5 years ago

"Flexture" refers to the type of mechanism that moves the sample stage relative to the objective lens. It means that instead of a high precision rack-and-pinion gear system that moves the stage, it uses "flexure joints" which don't necessarily need to be precision machined (they can be 3D printed).

In a flexture mechanism you apply force to a flexible bar and, because of geometry, that displacement gets translated and reduced into a much smaller displacement somewhere else. It only works with very small displacements (thus fine for microscopy). If you want to position the sample large distances, you just need to move the sample.

It's a neat idea made inexpensive by 3D printing, but the major expense here will be the optics (the objective lens). To get decent pictures of cells, like in a textbook, you're talking about $1K minimum, and it can go much higher, into the 10's, depending on application, performance and other optics (the light source and it's lenses).

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crispyambulance

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hasmanean  5 years ago

Is it possible to use software to post process those images, apply a deconvolution filter and correct the optics?

Might that enable the use of cheaper lenses?

  • colincooke  5 years ago

    Unfortunately you can't recover information that was never captured, which is the main issue with cheaper lenses. They tend to have more abberations [1], which prevents capturing high quality information.

    [1]: https://en.wikipedia.org/wiki/Optical_aberration

    • hasmanean  5 years ago

      Do all optical aberrations go away if you use a curved image plane?

      And if you correct aberrations in software then you can use the cheapest lenses (a single element objective and eyepiece) without having to correct for these aberrations in glass.

    • shard  5 years ago

      What if you shift the lens or sensor and capture multiple images, then process the result, would that be able to overcome chromatic abberation?

      3 replies →

dann0  5 years ago

No, a very good Chinese made RMS objective can cost less than $25 at lower magnification. Plan Achromatic objectives cost a little more, but will give flatter, clearer images than cheaper ones.

It seems a tube lens is used anyway, so the advantages of infinity system objectives are not as obvious. I’d stick to DIN160 or so called Olympus compatible objectives.

mlyle  5 years ago

You'd be surprised at what you can accomplish with a couple hundred dollar plan achromat objective. (Though OpenFlexure's design complicates the use of immersion oil...)