I need to compute the pixels projected from a 3D model that will end up inside the circle image area of the laparoscope image. I already know which pixels will appear in the rectangular image but I need to consider the case when I see the circle around. From my research I found that this circle is proportional to the apparent field of view of the endoscope but I haven't been able to find the way to compute it.
**If you know another way to compute the circle, it's welcome!
what kind of tool are you using ?
Just theoretical :
Since sensor array is 2D , the 3D point in space have to be transformed to 2D .
For which wither you consider perspective (this is ideal) or orthographic projection
https://www.scratchapixel.com/lessons/3d-basic-rendering/computing-pixel-coordinates-of-3d-point
Default : taking a conic section(say of a sphere) and then projecting on to the sensor (2D) like a circle's area after estimating the diameter.
The diameter can be width and height of illuminated (brightly )region based OR based on sources field of view (FoV) . Typically for a LED is is 20 degrees !!!
So if you use 8 LEDs then you have 20 *8 =160 degree (theoretical) . Again with light distance matters , so you can take steradian .
https://www.mathsisfun.com/geometry/steradian.html
Hello Aparna,,
Thanks for your answer. I'm not sure to understand what you mean with tool. I'm working on laparoscope pose estimation in an application for kidney. I'm considering a rigid laparoscope. What I know from the tool is the direction of the view that is usually 0 of 30 degrees but it can also be variable between 0 and 120 degrees. When you say estimation of the diameter, is it related with the diameter of the laparoscope?
I'll take a look to your suggestions and thanks again.
Like I briefly used Zemax (for understanding lens assembly design) + LightTools for source arrangement for a circular FoV.
Diameter is the FoV of the either source or lens ...
When you say apparent FoV do you mean the lens parameter :
https://www.edmundoptics.com/resources/application-notes/imaging/understanding-focal-length-and-field-of-view/
OR : source(s) LED or Laser ?
What I think is that the circle in the image depends on the zoom since the sensor in laparoscopes camera is bigger than the circular image. Hence, they should be a relation between the zoom and the size of the circle which is variable. But I think I can find some relation from the last link you sent me or at least I have some hints now.
Yes , zoom (lens dependent) and focal length are related .
I am not sure check Gullstrand's equation
http://hyperphysics.phy-astr.gsu.edu/hbase/geoopt/Gullstrand.html
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