目前市面上，規格比較好的液晶電視，都會配有照度感應器，其功能主要是依照環境光源照度的變化，來自動調整電子產品螢幕背光亮度，使人類眼睛接受到舒適的光線。此元件不單可節省能源，更可讓使用者觀看電視時更清晰亮麗，得到更漂亮畫質的效果。這個元件如人類的眼睛一樣，可識別四周環境的照度，以控制顯示器的背光亮度。 但由於照度感應器之輸出訊號送到接收 IC 為類比訊號，因此容易受到電路上其他雜訊的干擾，進而讓接收 IC 容易判斷錯誤環境光源的強度，使得電視自動背光調整的結果，並不符合當時的環境，這樣電視反而讓使用者看起來更不舒服。 本論文提出了一個雜訊濾波以及類比、數位轉換電路，可避免照度感應器受到雜訊干擾而隨意改變面背光，因此可大大增強電視對周圍環境光源偵測的準確性，營造出良好之觀賞空間。 此研究之設計 (濾波 + 類比/ 數位轉換電路)，優點有二： 1. 採用較低成本之電子元件，電路架構不至於太過複雜，應用在現有量產電視上，不會對終端售價產生太大的變化，業界接收、導入的意願高。 2. 電路架構為業界首創，幾乎配有照度感應器的電子產品，均可用此設計解決背光調整不穩定的問題，大大增加電子產品的賣點以及達到省電、節能的效果。;At present on the market, the LCD TV with better specification, already all have the function of 〝Ambient Light Sensor〞. Its function is mainly to use for adjusting the backlight luminance of electronic product automatically according to the change of the environmental illumination of light source and make human eyes accept the comfortable light. This component not only save the energy, but also let the user feel clearer and receive more beautiful result of picture quality when consumer watching the TV. The component almost the same as eyes of mankind, can discern the illumination of environment all around and in order to control the backlight luminance of the display. Because Ambient Light Sensor output is analog signal to send to the receive IC, so this analog signal is easy to be interference by the other ripple and noise on circuit. Cause the receive IC didn’t correct to estimate the environmental illuminance of light source. The result making the TV automatic backlight adjust function, does not fit with the environment at that time. In this way the TV picture lets the user look more uncomfortable. This research to show a kind of method for noise reduction and analog to digital converter circuit. It could prevent the ambient light sensor interference by noise and ripple, cause arbitrary change backlight luminance. So this study can strengthen the accuracy of TV for detected surrounding environment illuminance and build out good view space.
