As a final step, we will add a rectangular acrylic lightpipe 20mm to the right (+Z) of the Detector #5.

Add Rectangular Volume object in the editor, after Detector #5, with the following parameters:

Ref Object:  -1
Z position:  20
Material:  Acrylic
X1 Half Width  70
Y1 Half Width: 70
Z length:  2000
X2 Half Width: 70
Y2 Half Width: 70
All other parameters: Default

When entering the material type Acrylic, you might get the following message. Click Yes and ZEMAX will add to your file the MISC glass catalog, in which the material Acrylic is defined.

This time, we have set the Ref Object parameter -1, which represent the previous object in the editor (Object #5 Detector Rect). This is same as typing “5” for this parameter. Specifying relative object using negative number for the Ref Object is useful when group of objects in the editor are to be copied and pasted into the same or different non-sequential component editor.

Place another Detector Rect as object #7 in the editor with following parameters.

Ref Object:   -1 (referenced to Rectangular Volume, using the relative object reference)
Z position:  0 (we will change this value later)
Material:  Absorb
X Half Width:  100
Y Half Width:  100
# X Pixels:  150
# Y Pixels:  150
Color:   1
All other parameters: Default