• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 28 subscribers
  • Views 414 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.

Original question:

DLP470TP: getting projection beam same size as the DMD, without lens?

relationship between F-number and contrast?

Armen Tmsn
Intellectual 900 points

Is there some rule of thumb on how and how much changing the F-number of the projection lens changes the projection contrast? The fact that they are related has been mentioned several times to me but I can't find info on about how much it affects contrast to determine whether its worth asking the engineer to consider.

  • 0
    TI__Mastermind 23070 points
    Hi Armen,
    In a well designed optical system, our customers have been able to achieved ~1000:1 contrast ratio with F/1.7 optics, ~2000:1 contrast ratio with F/2.4 optics and more than 3000:1 with F/3.0 & higher. It very critical to minimize the stray light for good contrast.
    I hope this answers your question.
    regards,
    Vivek