自製烘豆機整體架構，包含紅外線穿透材料、熱風、紅外線發射管，是多元化的加熱模組。紅外線發射管的熱輻射，不需熱傳介質，有著良好的熱效應，並且其本身有著極高的熱電轉換效率，可以省掉大量的功耗，是值得選用的熱電元件。

本論文研究開發的紅外線穿透材料，經過高週波加熱實驗驗證，可高過加熱源溫度的優異表現，乃因兼具蓄熱與高放射特性。光譜穿透性能驗證，此材料中的200度、1000度的光譜數據顯示出中遠波長的穿透率分別達90%、80%以上，因此在中遠波段有良好的穿透率。咖啡豆內的水份吸收此波段的能量，達到烘焙的效果。

自製機與市售烘焙機進行烘焙結果的比較，經過色度、失重率與NIR進紅外光譜儀量測的比較後，其烘焙程度結果闡明，能區分出淺焙、中焙、深焙的結果。

關鍵字：紅外線、熱輻射、紅外線穿透材料、紅外線發射管、熱風、烘豆機

The overall structure of the self-made coffee roaster includes infrared penetrating materials, hot air, and infrared emission tubes. It is a diversified heating module. The thermal radiation of the infrared emission tube does not require a heat transfer medium, has a good thermal effect, and itself has a very high thermoelectric conversion efficiency, which can save a lot of power consumption, and is a thermoelectric element worth choosing.

The infrared penetrating material researched and developed in this paper has been verified by high-frequency heating experiments, and achieve higher temperature than a heat source due to possessing both heat storage and high emissivity. The spectral data of 200 degrees and 1000 degrees in this material shows the penetration of medium and long wavelengths. The penetration rate is over 90% and 80% respectively, so it has a good penetration rate in the mid- and long-range bands. The water in the coffee beans absorbs the energy of this band to achieve the roasting effect.

The roasting results of the homemade machine and the commercial roasting machine were compared. After comparing the chromaticity, weight loss rate and NIR into the infrared spectrometer, the roasting degree results were clarified, and the results of light roasting, medium roasting and dark roasting could be distinguished.

Keywords：Infrared、Thermal Radiation、Infrared Penetrating Material、Infrared Emission Tubes、Hot Air、Coffee Roasting.

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