Appl Opt. 2020 Mar 20;59(9):2858-2865. doi: 10.1364/AO.381815.
Accuracy in vein detection is important for intravenous applications such as venipuncture and other medical procedures. The near-infrared (NIR) imaging technique is used to visualize veins based on the difference of absorption of the infrared light by the oxyhemoglobin present in the blood and surrounding tissue. A problem commonly found during the visualization of veins is attributed to the source of light, saturation, low contrast, and dispersion, which are causes of inhomogeneous illumination. In this work, the design and implementation of a light source with LEDs in the range of 750-860 nm are presented. To obtain the design, a numerical simulation was made using the near-field diffraction theory to obtain homogeneous illumination at 40 cm of the sample, with a radial arrangement of three concentric LED rings. With the developed light source, an experimental scheme for the acquisition of vein patterns was implemented. Using a basic algorithm for the identification of intravenous patterns, a prototype was obtained that we believe can be used in intravenous applications and other medical procedures.
静脉检测的准确性对于静脉穿刺等静脉内应用以及其他医疗程序非常重要。近红外（NIR）成像技术用于根据血液和周围组织中存在的氧合血红蛋白对红外光的吸收差异来可视化静脉。在静脉可视化过程中经常发现的一个问题归因于光源、饱和度、低对比度和分散，这些都是不均匀照明的原因。在这项工作中，提出了一种在 750-860nm 范围内使用 LED 的光源的设计和实现。为了获得设计，使用近场衍射理论进行了数值模拟，以在样品的 40cm 处获得均匀照明，采用三个同心 LED 环的径向布置。使用开发的光源，实现了采集静脉模式的实验方案。使用静脉模式识别的基本算法，获得了一个原型，我们相信它可以用于静脉内应用和其他医疗程序。
