The imagiology using Narrow Band Light (NBL) is widely employed in detection of mucosa's premature changes of gastrointestinal tract, while taking advantage of light spectral features by enhancing the vascular structures without the application of any type of dye. NBL uses two specific spectral bands centered in blue (415 nm) and green (540 nm). Despite their greater advantages, this technique is not available on intra-corporal imagiology devices yet. Thus, this paper presents a low-cost method to adapt such devices without the need to develop specific and expensive LEDs (Light-Emitting Diodes) centered at 415 nm and 540 nm. The method combines optical filters with commercial LEDs to provide transmitted light with the desired peaks at 415 nm and 540 nm. Two optical filters were designed and fabricated, using 7 thin-films layers of SiO2 and TiO2 deposited by RF sputtering. The measurements showed that the transmitted light through the filters presented relative transmittance peaks located at 414 nm and 542 nm wavelengths with relative transmittances of 31% and 62% and FWHM (Full-Width-Half-Maximum) of 17 nm and 29 nm, respectively. The measurements also showed significant relative transmittances located at NBL central wavelengths of 415 and 540 nm with 30% and 60%.

中文翻译：

---

用于成像设备上窄带光适应的滤光片

使用窄带光 (NBL) 的影像学被广泛用于检测胃肠道粘膜的过早变化，同时通过增强血管结构而不使用任何类型的染料来利用光谱特征。NBL 使用两个以蓝色 (415 nm) 和绿色 (540 nm) 为中心的特定光谱带。尽管它们具有更大的优势，但这种技术在体内成像设备上尚不可用。因此，本文提出了一种低成本方法来适应此类设备，而无需开发以 415 nm 和 540 nm 为中心的特定且昂贵的 LED（发光二极管）。该方法将滤光片与商用 LED 相结合，以提供在 415 nm 和 540 nm 处具有所需峰值的透射光。设计并制作了两个滤光片，使用通过射频溅射沉积的 7 层 SiO2 和 TiO2 薄膜层。测量结果表明，通过滤光片的透射光在 414 nm 和 542 nm 波长处出现相对透射率峰值，相对透射率分别为 31% 和 62%，FWHM（全宽半最大值）分别为 17 nm 和 29 nm . 测量还显示位于 415 和 540 nm 的 NBL 中心波长处的显着相对透射率分别为 30% 和 60%。