News Release：Pioneer’s Terahertz Scanner Contributes to Research into the Preservation Condition of Takamatsuzuka Tomb's Wall Paintings in Nara Prefecture, Japan

Research to determine the preservation condition of the Takamatsuzuka Tomb's wall paintings was conducted by the Nara National Research Institute for Cultural Properties from February 29 to March 2, 2016, and Pioneer’s terahertz scanner was utilized for it. This is the first time that the terahertz scanner made by a Japanese manufacturer was adopted in this research.

The Takamatsuzuka Tomb, which is located in the Asuka Historical National Government Park in Nara Prefecture, is a circular tomb built between the 7th century and the beginning of the 8th century, and it is renowned for its colorful wall paintings depicting a group of female figures on the inside walls of the stone burial chamber. Since its excavation in 1972, the wall paintings have been damaged by fading and discoloration due to the penetration of rainwater and mold, and it was possible that peeling may occur. The stone burial chamber was therefore disassembled and moved to another location, and work to preserve and restore them began in 2006.

Terahertz waves are electromagnetic waves that have the characteristics of both light and radio waves. While they penetrate cloth, paper, wood, plastic, and ceramic, they do not penetrate metal and water. Our terahertz scanner, which takes advantage of these characteristics, consists of a high-precision scan mechanism with a light, compact main unit and head unit, and it is able to measure wall paintings of diverse sizes and shapes. In this research, our scanner precisely captured the transmission image inside the plaster layer where the wall paintings were depicted, and confirmed the level of degradation of the wall paintings.

Our terahertz scanner was also used last year for measuring the internal structure of “The black lacquered zushi (miniature shrine)” of the Teizo Kimura Collection owned by the Aichi Prefectural Museum of Art. In addition to the measurement of cultural properties, various applications to make effective use of terahertz waves are being considered, including applications for confirming the peeling off of general buildings and for security purpose.