- Thread starter nikosb
- Start date

What is the easiest way for you to show me what I need to know to use it?

In the second box you'll input the divergence. A protractor is useful to do that if this is done for a raw diode. Now we get to the next set of boxes. Let's keep it simple; and use only two lenses, one a negative lens, the other a positive lens. In the first box input the focal length of the negative lens ex. like this -6. This app assumes all lenses are positive unless designated otherwise. Spacing of the first lens is arbitrary if this app is used to make a beam expander. If this is used to make an optical system for a raw diode than spacing of the negative lens will have to be place close enough that the beam directly from the diode is not truncated. Now, input the second lens which for example has a focal length of 50mm, decrease the spacing by a small amount ex. to say 44.9, watch the graphic, increase the spacing by a few millimeters, watch the graphic and the numbers below the graphic. Start at a spacing of 50mm. You'll also notice several columns listing information, the one that is important to understand is the one which reads "Beam Diameter at Surface" what that means is the diameter of the beam as it meets the positive lens. You'll need a lens of a larger diameter so the beam is not truncated.

If you want to collimate for lowest divergence watch the graphic. When the lines representing the beam run parallel that's the lowest divergence. More questions just ask.

Last edited: