Winlens lab instructions

The Windows menu
When you have many windows open, you may want to use the Windows menu
to find windows that have gone missing behind other windows. The System
Parameter Editor is always number 1 in the list, and the System Data Editor is
always number 2 – so you can access these from the keyboard by pressing Alt-
W-W-1 or Alt-W-W-2, respectively. The Tile Vertically option fills the
workspace with all open windows, and gives them equal sizes. You cannot undo
this, so if you have arranged the windows to a layout you like, don’t use this
option. The Cascade option puts the windows on top of each other, slightly
displaced so you can see all of them. Like Tile Vertically, Cascade cannot be
undone.
Adding a lens
A catalogue lens
In this section we set up a simple imaging system with one single lens and have
a look at some of its characteristics.
To open a catalogue of lenses with their respective design data,
• open the menu Data Base (ALT-D) and then choose Component Data
Base (SHIFT-C), or quicker: press F3 2
If you look at row 339 you will find an achromat, with focal length f=100mm,
and part no (NoMount) 322288000. If you don’t see it, click Full Database, and
it should appear. Click on the part no, and WinLens gives you a drawing of the
lens and informs you that the focal length is 100.04 mm at wavelength 587.6
nm, and that the diameter is 31.5 mm. To add the lens to your system,
• drag and drop the part no to the Component column in the System Data
Editor.
Now the lens is in place. (Typing the number into the Component column has
the same effect.) “Stop” on the same row as the lens means that the aperture stop
is immediately in front of the first surface of the lens.
The next step is to set the parameters of the imaging system. The System
Parameter Editor is where you do this. Look at the Main tab. Here you find,
among other things, the object distance. Its default value is –1000mm. To place
the object at infinity,
• change to the Conjugates tab and click the radio button Object at
Infinity.
To set the size of the aperture stop,
• go to the Aperture tab.
There, you find a number of different terms (NA, F/No etc) all describing the
size of the stop. If you are primarily interested in the flux of light through the
aperture, you should set the stop radius. To set the stop radius:
• click the Stop Rad radio button. Then enter the desired stop radius, say
5.0 mm, into the text box to the right of the radio button. Press Enter
and WinLens calculates the values for NA, F/No etc and fills in their values.