This is the VOA Special English Economics Report.
这里是美国之音慢速英语经济报道。
When we print something, a flat page comes to mind. For example, you might use a photocopier.
当我们打印东西的时候，就会想到平滑的纸张。例如，你可能会使用复印机。
Photocopiers print in two dimensions.
复印机打印出来是二维的。
Now, imagine how this would work for three dimensions. A machine prints layers of material—usually plastic—one on top of the other. The layers are very thin—usually one-fifth or one-tenth of a millimeter. The layers then combine to form a solid object.
现在，想象一下，如果是三维打印，应该是如何工作的？三维打印机打印一层层的材料 -- 这种材料通常是塑料 -- 层层叠加起来。每层都非常薄 -- 通常只有1/5或1/10毫米。然后各层组合成一个坚固的物体。
There are many versions of this kind of technology. But the basic idea is the same for most 3-D printers. The process is called additive fabrication.
三维打印技术存在多种版本。但对大部分的3D打印机来说，基本原理都相同。这个过程被称为迭加成形（additive fabrication）。
注:所谓3D打印机就是可以“打印”出真实3D物体的一种设备，功能上与激光成型技术一样，采用分层加工、迭加成形，即通过逐层增加材料来生成3D实体，与传统的去除材料加工技术完全不同。称之为“打印机”是参照了其技术原理，因为分层加工的过程与喷墨打印十分相似。
These 3-D printers have become powerful tools for product designers. Computer-aided design programs use software to direct the printer. Designers can then create a solid model in a short time and easily make changes and tests.
这种三维打印机已经成为产品设计者的得力助手。计算机辅助设计程序使用软件来控制打印机。这样设计者可以在很短的时间内创建实体模型，并且修改和测试极其简单。
The 3-D printing technology was first developed in the nineteen eighties. But high cost put them out of the reach of many researchers and businesses. Early printers were limited. High cost and limited uses meant the 3-D printer market was small.
三维打印技术最早成型于20世纪80年代。但高昂的成本将其置于大多研究人员和企业界遥不可及的位置。早期的三维打印机应用范围有限，高昂的成本和有限的应用范围也意味着三维打印机的市场很小。
Now, lower-cost printers are available to a much wider market, including small businesses and individuals.
现在，低成本的三维打印机获得了更广阔的市场，包括小型企业和个人都可以使用。
In January, the global technology company Hewlett-Packard agreed to sell 3-D printers manufactured by Stratasys. Stratasys has made 3-D printers for years. Last year, it introduced one for less than fifteen thousand dollars.
今年1月，跨国科技公司惠普同意销售Stratasys公司制造的三维打印机。Stratasys公司生产三维打印机多年。去年，它推出了一款不到1.5万美元的三维打印机。
More companies are using 3-D printing to directly manufacture some products. For example, Freedom of Creation, based in Amsterdam, the Netherlands, prints furniture and art. Bespoke Innovations in San Francisco, California wants to design and print artificial limbs. Co-founder Scott Summit says these prosthetic limbs can be designed exactly for a patient's body for less money than existing products.
越来越多的公司正在使用三维打印机来制造某些产品。例如，总部位于荷兰阿姆斯特丹市的Freedom of Creation公司用三维打印机打印家具和艺术品。加利福尼亚州旧金山市的Bespoke Innovations公司希望用三维打印机设计和制作假肢。该公司的联合创始人斯科特·萨米特（Scott Summit）表示，这种假肢可以为病人量身定做，且价格比现有产品低。
But 3-D printing still has limits. For example, metals are more difficult to print than plastics. However, airplane maker Boeing prints some airplane parts. And printers are being used to create some rare parts for old machines.
但三维打印机的使用范围仍然存在一些限制。例如，金属制品要比塑料制品更难打印。然而，飞机制造商波音公司用三维打印机打印了一些飞机零部件。同时，三维打印机被用于制造一些老机器的稀缺零部件。
For people interested in new technology, a New York based company, Makerbot, sells kits to people who want to build a small 3-D printer. Some kits cost less than one thousand dollars.
对于那些对新技术比较感兴趣的人，总部位于纽约的一家名为Makerbot的公司，向这些希望组装一台小型三维打印机的人出售零件包。有些零件包价格低于1000美元。