臺灣博碩士論文加值系統

對於一般市面上的可攜帶式電子產品例如手機、PDA、及筆記型電腦而言，微型化是目前發展的趨勢。因此，如何將其所組成的模組縮小便是首要任務。對於鏡頭模組而言，傳統上使用步進馬達來驅動的鏡頭模組在微型化的過程中已經遇到了瓶頸，因為這樣的系統無論是在自動對焦或是光學變焦的過程中，都需要空間來移動鏡子。一種解決的方式是結合反射式光學以及利用微機電系統技術所製造的可形變鏡面。反射式光學不但有低色散的特性，並且因為其原理是將光路在系統內反射數次後再成像於系統之外，整個系統的大小可以縮小許多；另一方面，由微機電系統技術所製造的可形變鏡面，不但適合大量製造，其光學上的等效焦距也是可調變的。結合這兩種技術，在本文中我們將討論如何設計並實現一個長約8.5毫米、寬約4.5毫米的自動對焦系統並討論其改進方法及可能性，以及如何運用這兩種技術來設計一個微型光學變焦系統。

Miniaturized imaging system is the modern trend in commercial products, especially for portable devices such as mobile phones, PDAs, and computer laptops. However, motor-driven lens modules in conventional cameras are difficult to be miniaturized since they require space to achieve auto-focusing and zooming function. One possible solution is to combine the reflective optics, which features low color dispersion, and MEMS deformable mirrors, which feature tunable focal length. What’s more, reflective optics is space-efficient by bending optical path several times within the system. Combining these two technologies, we present an optical design of an auto-focusing system with only 8.5 mm in length and 4.5 mm in thickness. Besides, we also discuss some possible ways to improve our auto-focusing system, and how reflective optics and MEMS deformable mirrors can be applied to compact zoom systems.

ABSTRACT i
中文摘要 ii
致謝 iii
LIST OF FIGURES vii
LIST OF TABLES x

CHPATER 1: INTRODUCTION 1

CHAPTER 2: MEMS-BASED ORGANIC DEFORMABLE MIRRORS 3
2.1 Adaptive Optics and Deformable Mirrors 3
2.2 Micro-electro-mechanical Systems (MEMS) 5
2.3 MEMS-based Organic Deformable Mirrors 7
2.3.1 Fabrication Process of MEMS-based Organic Deformable Mirrors 7
2.3.2 Optical Properties of MEMS-based Organic Deformable Mirrors 10

CHAPTER 3: AUTO-FOCUS SYSTEM AND ADAPTIVE OPTICS 13
3.1 Traditional Auto-focus System 13
3.1.1 Driving Power of Traditional Auto-focus Systems 13
3.1.2 Basic Theory of Traditional Auto-focus Systems 15
3.2 Auto-focus System with Adaptive Optics 16
3.3 Two Types of Adaptive-optical Components 17
3.3.1 Refractive-type Adaptive-optical Component 17
3.3.2 Reflective-type Adaptive-optical Component 19

CHAPTER 4: AUTO-FOCUS SYSTEM WITH DEFORMABLE MIRROR FOR PORTABLE DEVICES 22
4.1 Previous Works 22
4.2 Modified Auto-focus System 24
4.2.1 Simulation Results When MEMS Mirror Is Flat 26
4.2.2 Simulation Results When MEMS Mirror Is Actuated 28
4.2.3 System Packaging 29

CHAPTER 5: EXPERIMENTAL RESULTS AND DISCUSSION 31
5.1 Experiment Devices and Setup 31
5.1.1 Acrylic Solid Lenses 31
5.1.2 Lens Module Package 33
5.1.3 CMOS VGA Image Sensor 36
5.1.4 Miniature High Voltage Power Supply 37
5.2 Experiment and Results 38
5.3 Discussion 41

CHAPTER 6: ZOOM SYSTEM WITH DEFORMABLE MIRRORS FOR PORTABLE DEVICES 43
6.1 Traditional Zoom Theory for Moving Lenses 43
6.2 Zoom Theory for Stationary Components 44
6.2.1 Magnification According to “fm1” and “fm2” 45
6.2.2 Keeping The Distance Between Object and Image a Constant 47
6.3 An Example of Zoom Theory 48
6.4 Using The Zoom Theory 51
6.5 Conclusion of Zoom Theory 54

CHAPTER 7: CONCLUSION AND FUTURE WORK 56
7.1 Conclusion 56
7.2 Future Work 57

REFERENCES 59
Appendix 1: LIST OF PUBLICATIONS 61
Appendix 2: DETAILED AUTO-FOCUS SYSTEM DESCRIPTION 62
Appendix 3: EXCEL® OF ZOOM THEORY 63

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