裸眼3D全息技术来了！

    你如果认为当今电影和电视节目里的三维技术很酷，那就等你看到全息图像沙盘再说这话吧。在美国国防部的研究机构——国防部高级研究计划局（DARPA）的资助下，城市激光沙盘显示设备公司（Urban Photonic Sandtable Display）制作出了一种用于作战计划的360度三维图像（无需用镜子折射）。正在开发这项技术的斑马图像制作公司（Zebra Imaging）称，还需要至少三年的时间才能将这种沙盘应用于外科手术方案，甚至用于赌牌等商业目的，但这并不能阻止我们现在就想象一下其潜在的用途。以下是它的工作原理。

虚拟模型

    先使用普通设计软件或者激光扫描测距（LIDAR）设备，用各种肉眼看不见的激光扫描实体建筑物和物品，以形成详尽的三维图像。

制作全息图像

    再使用普通电脑上装载的一种专利软件插件，将三维图像转换成适合制作全息图像的格式。在这个阶段，用户可拉近、推远、旋转或者改变光线。

成像显示

    沙盘显示器内置的处理器和图形处理单元对这些数据进行处理后，通过一台光调制器和一组透镜把信息传输过去，便可做出一个由数以百万计的“全息素”——相当于三维像素——构成的图像。

    译者：王恩冕

    If you think today's 3-D technology in movies and TV shows is cool, wait until you see your first hologram table. Funded by DARPA, the Defense Department's research arm, for battle planning, the Urban Photonic Sandtable Display produces a 360°, 3-D image (no glasses needed). Zebra Imaging, the company that is developing the technology, says it'll take at least another three years before this table is set for business applications like surgical planning or even gaming, but that won't stop us from thinking about the possibilities now. Here's how it works.

    Virtual models: Detailed 3-D renderings are created from standard design software or Light Detection and Ranging (LIDAR) devices that sweep real-world buildings and objects with invisible lasers.

    Prepping the hologram: A proprietary software plug-in loaded onto a standard computer converts the 3-D image into a hologram-friendly format. During this stage, users can zoom in or out, rotate, or change the lighting.

    The display: Processors and graphics-processing units inside the display crunch the data and send it through a light modulator and a set of lenses to create an image made up of millions of "hogels," the 3-D equivalent of pixels.