Disclosures of the present invention describe a use of light source for inhibiting melatonin secretion. In the present invention, an illumination device is particularly configured for emitting an illumination light with a specific wavelength that is in a range between 581nm and 590nm, and a variety of experimental data have proved that the illumination light functions as a melatonin secretion inhibitor. Therefore, the illumination device of the present invention is evidenced to be suitable for use in light therapy, so as to treat seasonal affective disorder (SAD) by way of inhibiting melatonin secretion. Briefly speaking, after a SAD patient received the irradiation of the illumination light having wavelength ranged in 581-590 nm for a treatment course, the SAD patient is eventually leaded to stay in good spirits and a stable condition of emotion, thereby curing the abnormal symptoms of sleepiness and emotional disorder.本發明提供一種光源於抑制褪黑激素分泌的用途。在本發明中，一照明裝置被特別設計用以發射具有波長範圍介於581nm和590nm之間的一特定波長的一照明光，且各種實驗數據已經證明此照明光可以被使用作為一褪黑激素分泌抑制劑。因此，實驗數據已證實本發明之照明裝置適用應用在冬季憂鬱症之燈光療法，從而通過抑制褪黑激素的分泌來治療季節性情感障礙(即，冬季憂鬱症)。 簡言之，在冬季憂鬱症患者接受波長範圍在581-590nm的照明光的一光療療程之後，冬季憂鬱症患者最終會因為具有良好的精神狀態和穩定的情緒狀態，從而治癒其冬季憂鬱症之症狀，包括嗜睡、情緒障礙等。
