CHENGDU, March 28 (Xinhua) -- Liao Zihua holds a 3D laser scanner to conduct an inspection of an old building in Chengdu, capital of southwest China's Sichuan Province.

In just a minute, a detailed 3D photo of the building is complete, creating a valuable tool for archaeologists in historic preservation.

"Using a laser scanner is quick and highly precise. It can detect the building's structure, data and original color and is very useful for future restoration," said Liao, an engineer at the Sichuan Academy of Safety Science and Technology.

"Some of these antiquities are suffering invisible damage, which is easy to identify after going through a laser 'body check,'" Liao added.

"The 3D photos are precise down to the millimeter. It allows visitors to admire the big picture of the buildings while also observing their exquisite details," said Wang Lijuan, head of the 3D technological institute of the academy.

3D laser scanning is increasingly being applied in the preservation of cultural relics in China. The institute has archived 3D images of many well-known sites including Deng Xiaoping's former residence, part of the Chengdu Wuhou Shrine, the Ganxi ancient tower and the ancient Tibetan village in Ganzi Tibetan Autonomous Prefecture in Sichuan.

In 2013, Wang's team spent a week creating images of the Tian'anmen Rostrum. They also made a 3D vector data model of the rostrum, which now provides important technical support for the restoration, cleaning and protection of the site.

The new technology has significantly improved efficiency and accuracy in historic preservation.

Traditionally, researchers have had to use a measuring tape and cameras to manually measure the antiquities, and a ladder is often needed to measure the top, leading to inaccurate data.

"Take a temple complex in Sichuan's Leshan for example. Measuring used to take five people two months to finish, but last time, using laser scanning, we completed it in just two weeks," said Tang Fei, vice president of the Sichuan Provincial Cultural Relics and Archaeology Research Institute.