Transcript Synopsis of Technical Report: “Lens Mounting Techniques

OPTI 521 – Fall 2008
Houssine Makhlouf
December 8th, 2008
Content
 Techniques to mount individual lenses
 Analysis of stress in glass-metal interface
 Application to real systems
 Comments and conclusions
Mounting individual lenses
1/ Lens burnishing
 Malleable material
 Hardened tool pressing
 Bent cell lip retains lens
Mounting individual lenses
2/ Snap ring
 Groove inside cell
 Insert fitting snap ring
 Hard to remove
 Quite permanent
assembly
Mounting individual lenses
3/ Elastomer injection
 Gap between lens and
cell
 Fill gap with resilient
material
 Hold lens axially
 Inject and let cure
Mounting individual lenses
4/ Threaded retainer
 Press lens against seat
 Use threaded retaining
ring
 Holds lens firmly
 Repeatable
 Mount several elements
in same housing
Mounting individual lenses
Cut for seat and retainer
 Square shape
most common and easiest to machine, can be beveled to
reduce nicks and burrs
 Tangent to lens surface
axial misalignment issue
 Spherical with same radius of curvature as lens surface
hard to make precisely and expensive
Mounting individual lenses
Cut for seat and retainer
Stress in glass-metal interface
 Constrain lens position is important
 Mounts cause stress
 Stress depends on type of contact and temperature
change
 Tangential contact reduces dramatically preload stress
 Models and formulas in Yoder’s paper
Some real system designs
Military use or severe environment
Comments and Conclusion
 Paper reports on lens mounting which is intended for
all opto-mechanical scientists
 Author computations show that special care about
designs is really required for specific applications
involving severe environment issues
 Laboratory-type environment is pretty safe