臺灣博碩士論文加值系統

隨著資訊產業的蓬勃發展，光儲存產品也不斷變化，然而技術提升 伴隨而來即是較大的振動及噪音，尤其是噪音與使用者最有直接關係， 也是最為人所詬病的地方，因此，了解光碟機產生噪音之機制，進而降低光碟機的噪音實為一重要之工程課題。

光碟機在高速運轉下所產生的噪音，有兩種。第一是因為光碟片本身高速運轉，使得週遭的氣流也跟著流動，光碟片受到週遭氣流而造成擺動的現象，因而產生噪音，稱為空氣動力噪音。第二是因為主軸馬達在高速轉動時，與光碟機產生的振動所引發的噪音，稱為結構振動噪音。

本論文藉由改變光碟片翹曲量，於光碟機下不同轉速下探討對噪音的影響，另外加入吸音泡棉一起做探討研究， 分別針對無貼附泡棉、高密度吸音泡棉及低密度吸音泡棉作實驗，最後找出最佳之搭配組合。

Following by the development of information industry, the optical storage is changed dramatically. However, the issue of vibration and noise is largely increased with the progressing of the technology. Therefore, to find out the cause of noise of DVD-ROMs and to reduce the noise of DVD-ROMs are important engineering issues.

There are two kinds of the noises generated when DVD-ROM running in high speed. The first one is aerodynamic noise and the cause is : the spindle motor drives disk rotating in high speed and the surrounded air would flow accordantly. Then the disk is vibrating due to the air flow which would cause noise. Another kind of noise is called structure vibration noise, which is generated by the vibration of DVD-ROM when spindle motor is running in high speed.

In this paper will show the influence of the different Disc-Vertical Deviation of DVD-ROMs on noise under the various high speed of spindle motor. Moreover, noise absorptive foams are included in this study. The experiment included the following three conditions: without using noise absorptive foam, attached with high density noise absorptive foam, and low density noise absorptive foam. Finally, the optimal combination will be identified according to the result of this experiment.

中英文摘要 I
目錄 Ⅲ
圖目錄 Ⅴ
表目錄 Ⅷ
第一章 前言 1
1.1 研究動機 1
1.2 文獻回顧 2
1.3 研究目標與方法 4
第二章 理論基礎 6
2.1 光碟片基本理論 6
2.2 光碟機之理論基礎 10
2.3 噪音基本理論 11
2.4 吸音基本原理 13
2.5 振動傳播原理 17
2.6 聲音的基本參數 19
第三章 實驗設備與方法 26
3.1 實驗設備 26
3.2 實驗方法 31
第四章 確認碟片翹曲量與吸音泡棉對噪音之影響 35
4.1 光碟片翹曲量之樣本製作 36
4.2 光碟片翹曲量對噪音的影響 47
4.3 光碟機貼附吸音泡棉對噪音的影響 56
第五章 結論 73
參考文獻 75

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