• State TI Thinks Resolved
  • Locked Locked
  • Replies 2 replies
  • Answers 1 answer
  • Subscribers 28 subscribers
  • Views 815 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

NIR Lenses

Marco Tramacere
Prodigy 155 points

Hello

I want to know why the lenses aren't simply Plano convex lenses? I see from the assembly drawings that the lenses, got from Optimax, have a little curvature in the "plano" region. Why this? Is it a reason linked to focusing problem?

Moreover I'd want to know if I may change all 6 lenses and replace them with other 6 (plano convex) which work in spectral range (900nm-2500nm) of my interest.

(I am worried that if I put 6 plano convex lenses in the system I would ruin the focusing or something similar)

Final query: Optimax doesn't seem an online "Store". Do you think that if I request them 6 lenses with same dimensions of those placed in NIR scan nano EVM, but working in the spectral range mentioned above, they might provide them to me?

Thank's a lot

  • 0
    TI__Guru 54675 points

    Marco,

    The design team will need to be consulted to answer this question.  It may take a couple of days.

    Fizix

  • 0
    TI__Guru 54675 points

    Hello again Marco,

    Here is the  response from the TI DLP NIRscan-Nano design team:

     

    Four of the six lenses in the Nano actually are plano-convex, but the first two 2 immediately after the slit are not. Allowing curvatures on both sides resulted in better imaging performance on the slit to DMD path. Simply dropping in plano-convex lenses in their place would likely not work. Even if you managed to keep the focal plane at the DMD, it would introduce aberrations into the imaging path which would degrade the spectral resolution, possibly very severely.

     

    Trying to swap out lenses like that would very likely require an optical designer to modify the zemax design to accommodate the changes, just dropping in random off the shelf components will not be successful. The lenses would also mount differently in the chassis.

     

    You also mentions 900-2500nm measurement range. The anti-reflective coating on the lenses is certainly one issue with trying to change the measurement range, but far from the only one. Optimax will happily manufacture lenses with different coating specifications, although 900-2500nm is very broad and might be challenging. However, it is likely be quite how expensive to have Optimax manufacture anything, it is orders of magnitude higher than buying things from Newport, Thorlabs, Edmund, etc. . .  for instance.

     

    Unfortunately, even with appropriate coatings, the Nano will not support a 900-2500nm measurement range.

     

    Here are some other E2E posts that might be useful:

     

    NIRscan or Nano NIRscan use at 575 nm possible and what would be needed? 

     

    Extend the spectral range of NIRscan Nano 

     

    DLP-NIR systems

    I hope this helps.

    Fizix