Page 168 - Chalcogenide Glasses for Infrared Optics

144 Cha pte r S i x

FIGURE 6.11 Photograph of a molded 5.38-in-diameter Amtir 5 JSF lens.

AMI found itself in a seemingly impossible situation when an
agreement was made to mold a lens 8 mm in diameter. Early attempts
proved fruitless. Another approach was needed. We decided to place
a thin metal ring in the mold, the outside diameter the same as the
bottom of the mold and the height of the ring the same as the lens
edge, so the glass would bond to the ring. The lens could then be
removed because the metal ring would not stick to the metal mold.
The scheme worked, and the 8-mm lens fell right out. Figure 6.12
shows a fuzzy photo of the 8-mm molded lens encased in the metal
ring at the base. Figure 6.13 shows a diagram of the scheme we
followed. Another example is shown in Fig. 6.14. In this case, a fragile

FIGURE 6.12 Photograph of a molded 8-mm-diameter lens in a metal ring.