在工業的領域，工程師經常面臨到一些需要使用感測器去量物體
的位置、速度、加速度來獲得系統運動時相關的資訊。在本篇論文裡，
我們提出使用三個光學讀頭來實現平面定位的方法，利用讀頭在循軌時
產生的循軌誤差訊號來計算跨越的軌數，因此可以得知讀頭所移動的距
離及位置。
當物體只進行平移的運動時，只需要兩個讀頭就可以知道物體移動
的距離及位置，但當物體並非進行平移時，也就是同時進行旋轉之運動
時，兩個讀頭則無法得知物體真正的運動量，而必須使用三個讀頭。利
用每一個光學讀頭所能量測到之移動量，經由計算後即可得知物體真正
的位移量及旋轉角度。由於光碟片的軌距為1.6 ，因此整個定位的精密
度可以達到1.6 之內，而物體旋轉量在90度以內均可利用本系統來量測
。

In the field of industry, the engineer often confronts with
problems demanded with transducers for position, velocity, and
acceleration of the object. In the thesis, we present a method
for measuring plane position with a commercially available
compact disc optical pickup. The method is used the tracking
error signal generated by the optical pick-up head during
tracking to count the track numbers. Thus, the distance which
the pick-up head has been moved, and the position of the
pick-up head can be measured.
When the object is doing translation, we only need two
pick-up heads to measure the displacement and the position of
the object. But if the motion of the object is not only the
translation but also the rotation, two pick-up heads are not
enough for us to measure. Thus, we need three optical pick-up
heads. The displacement of the pick-up head can be measured to
calculate the actual displacement and rotation angles of the
object. The distance of track is 1.6 , hence, the accuracy of
the positioning system is achieved to 1.6 . In this implement
we can measure displacement of pickup set which rotation less
90-degree.

Contents
摘要………………………………………………………………………i
Abstract…………………………………………………………………..ii
Contents…………………………………………………………iv
CHAPTER 1 INTRODUCTION………………………...…….1
CHAPTER 2 OPTICAL PICKUP SYSTEM………………..2
Section 2.1 Optical Pickup………………………………………..….…
..3
Section 2.2 Focus Sensors………………………………………………
..6
2.2.1 Astigmatic method…………………………………………………6
2.2.2 Knife-edge Method………………………………………………...7
Section 2.3 Tracking Method…………………………………………….8
2.3.1 Three-Spot Method………………………………………………...8
2.3.2 Push-Pull Method…………………………………………………10
Section 2.4 Basic signal………………………………………………
...11
Section 2.5 Decision of Direction………………………………………
12
Section 2.6 Pickup Actuator……………………………………………
.15
CHAPTER 3 CONTROL CIRCUIT……………………….16
Section 3.1 Signal Amplifier …………………………………………
...16
Section 3.2 Servo Chip………………………………………………….19
3.2.1 MT1105 Overview ……………………………………………….19
3.2.2 Microprocessor Interface…………………………………………
20
3.2.3 Addressable Registers……………………………………………
.21
3.2.4 Command Set……………………………………………………..23
3.2.5 Focus Servo Loop………………………………………………...24
3.2.6 Focus Servo Relative command …………………………………
.25
CHAPTER 4 PROGRAMMING…………………………...30
Section 4.1 Franklin Compiler…………………………………………
.30
4.1.1 Microcomputer Language Extensions……………………………
.30
4.1.2 Focusing Program Flow…………………………………………..31
Section 4.2 P-ICE Emulator…………………………………………….32
Chapter 5 Implementation…………………………………..34
Section 5.1. Experiment Flow and layout………………………………
34
Section 5.2. Monitor S curve …………………………………………
...35
Section 5.3. Measure Plan Position ……………………………………
.36
Chapter 6 conclusion………………………………………...39
References………………………………………………………………40

References
1. MEDIATEK, CD-ROM Digital Data/Servo Processor MT1105F, 1998.
2. MEDIATEK, CD-ROM Signal Amplifier MT1126F, 1998.
3. DEEMAX TECHNOLOGY, INC. P-ICE 8051, 1997.
4. 鄭時龍, A High Resolution Position Encoder Using an Optical
Pickup. of CD Player, 交通大學機械工程學系博士論文, 1996,
Chapter 2.
5. KENC. POHLMANN, The Compact Disc, Oxford University Press,
1989, p165~p225.
6. 鄧錦城, 8051組合語言, 益眾資訊有限公司, 民82, 第一章, 第四章
.
7. 卓聖鵬, 光碟技術入門, 全華科技圖書股份有限公司, 民84, 第二章
, 第三章.
8. 郭立華, 光學頭致動器機構簡介, 光電資訊雜誌第二十七期, 民84,
p14~p17.
9. 朱朝居, CD-ROM光碟機之光學頭, 光電資訊雜誌第二十一期, 民83,
p16~p25.