3D-TV是電視未來發展的趨勢，且有越來越多的研究著重在3D-TV，我們相信在未來3D-TV將會取代現在的高畫質電視。近幾年來，3D-TV系統發產出一種Depth Image Based Rendering(DIBR) [2]的技術，DIBR只需傳送二維影像跟二維影像所對應的深度資訊(depth map)就可以透過立體顯示器使觀賞者觀看到立體的效果，且DIBR相較於傳統傳送左、右兩張影像來產生立體視覺的方法，DIBR對頻寬、編碼、儲存的需求是比較少的，這對整個3D-TV系統有相當大的幫助。
得到深度資訊的方法有很多種，在被動式的方法中，利用焦距的線索來求深度資訊又可以分為利用影像清晰程度(depth from defocus)跟影像模糊程度(depth from defocus)兩大類。相較於其它求深度資訊的演算法，spatial domain transform method(STM) [13] 是一個比較簡單、直觀的方法，所以我們選擇STM來求不同聚焦程度影像的深度資訊並使用硬體描述語言去設計其硬體架構，在Xilinx FPGA來實現設計的原型。
至於影像的取得，我們是藉由改變液晶變焦相機(Liquid-Crystal Lens camera)的電壓來改變相機的焦距，利用相機焦距的改變來拍攝兩張不同聚焦位置的影像，並利用STM來分析這兩張影像的模糊程度，藉此建立深度資訊圖，並利用立體顯示器來觀看實驗結果。

Three-dimensional television (3D-TV) is the trend of television development in the future and there are many researches focus on 3D-TV. We believe that three-dimensional (or stereoscopic) television (3D-TV) will replace high-definition television (HD-TV). Recently, an advanced 3D-TV system has been brought up on the new technology called Depth Image-Based Rendering (DIBR), which is also called 2D-plus-depth. This representation is generally considered to be more efficient for coding, storage, transmission and rendering than traditional 3D video representation which is transmitting left image and right image to receiver.
There are many approaches to 3D depth recovery and the approaches of 3D depth recovery can be divided into depth from focus (DFF) and Depth from defocus (DFD) for focus cue. We choose spatial domain transform method (STM) [13] to estimate the depth information of different defocused images because STM is more simple and direct than other methods. We use Verilog HDL to develop the hardware architecture of the STM algorithm and implement the prototype on Xilinx FPGA board.
About acquiring images, the different defocused images were recorded by applying different voltage to Liquid-Crystal Lens camera. Then we estimate depth map from blur degree of images by using STM algorithm. And we use three dimensional display to watch the experiment results.

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