Online proceedings - EDA Publishing Association

11-13
May 2011, Aix-en-Provence, France
temperature 120 ℃ for 2 minutes. The OM photographs of
patterns before and after thermal reflow are shown in Fig. 9.
(a)
(b)
Fig. 7. The frame (a) and screen mold (b) for screen printing.
(a)
(b)
Fig. 9. OM photographs of patterns before (a) and after (b) thermal reflow.
III. RESULTS
The finish screen mesh mold has the average thickness
16μm. Eight microlens arrays with different patterns were
completed by using this screen printing process. The large
lens diameter trends to have a low sag height. An example is
shown in Fig. 10. Microlens with diameter 108.5μm, its sag
height is 3.87μm. Comparing a smaller microlens with
diameter 85µm, its sag height is 7.6µm. Since the screen
mold has the same thickness, the large lens diameter resulted
in a large radius of curvature. The sag height is getting
smaller. The experiment is successful to make the microlens
array in a simple manufacturing process with fast formation,
cost reduction and controllable microstructure appearance
advantages. The further related process technology is benefit
to optical lens industry.
(b)
Fig. 8. Pattern profiles of differenet mesh mold diameters; (a) 60μm, (b)
100μm.
(a)
(a)
(b)
Fig. 10. Microlens array fabricated by screen printing; (a) OM photograph,
(b) 3D profile.
IV CONCLUSION
The experiment was successful to use the screen printing
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