52300

Sensing and Actuation in Miniaturized Systems

Professor ： Cheng-Hsien  Liu

Students ： Den-Hua Lee

Tsu-Wei Huang

Topics ： Microlens array bio-sensing system

2008/11/11 1

Contents

• Introduction

• The Goal

• Discussion

• Conclusion

2008/11/11 2

Introduction

• Improved light out-coupling in organic light emitting diodes employing ordered microlens arrays. 2002

• A novel method to fabricate gapless hexagonal micro-lens array. 2004

• Microlens array film with full fill factor for enhancing outcoupling efficiency from OLED lighting. 2007

2008/11/11 3

Improved light out-coupling in organic light emitting diodes employing

ordered microlens arrays

S. Möller and S. R. Forrest

J. of Applied Physics, 91 p.3324-3327 (2002)

2008/11/11 4

PDMS microlens array fabricated from the mold

Si mold was etched in HNO3+CH3COOH+HF used Si3N4 layer as a mask

2008/11/11 5

Mold transfer process

Image blurring due to the thickness

Paper printout Lens sheet covered OLED with lens sheet covered

Covered area is brighter

2008/11/11 6

A novel method to fabricate gapless hexagonal micro-lens array

M.C. Chou, C.T. Pan, S.C. Shen, M.-F. Chen, K.L. Lin, and S.T. Wu

Sensors and Actuators A, 118, p298-306 (2005)

2008/11/11 7

Reflow process of AZ4620 thick PR forfabricating half-spherical column

Si

Ni as seed layerElectroplate Ni-Co moldCMPHot embossing PMMA2008/11/11 8

90% 45%

95% 100%

Different shape with different fill factor Distribution reflowing to form gapless hexagonal lens2008/11/11 9

Sequence of Ni-Co electroplating process Different gapless lens form by

different distributions2008/11/11 10

Laser passes through hot-embossed PMMA-based gapless hexagonal micro-lens.

2008/11/11 11

Microlens array film with full fill factor for enhancing outcoupling efficiency

from OLED lighting

Hyouk Kwon, Youngjoo Yee, Chi-Hwan Jeong1, Hyo-Jin Nam, Ki-Won Park, Gun-Woo Lee, and Jong-Uk Bu

uTAS proceeding, 2EK5P, p1091-1094 (2007)

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Micro Lens Array provide brightness increasing

Higher fill factor, higher efficiency

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Conformal coating process decrease the height of lens

Applying trench to keep higher sag height

Trench structure keep lens’ shape closing to half-spherical

Outcoupling efficiency according to the sag ratio

2008/11/11 14

MLA is made by UV stamping on transparent PET film2008/11/11 15

31.3% improvement2008/11/11 16

OLED with MLA looked brighter2008/11/11 17