A method of laser ultrasound tomography for solid surfaces mapping

Abstract

Abstract. Surface control is an important problem for production inspection in industry. Traditionally it is solved using mechanical and optical profilometry, providing high spatial resolution. However, such methods are inappropriate for bodies immersed in opaque liquids and require preliminary preparation of samples. Current work focuses on an application of a method of laser ultrasound tomography to mapping of solid surfaces. The suggested approach combines high acoustical resolution, high performance and allows profilometry of contaminated and immersed samples. An automated prototype for real-time surface profile measurements is constructed and tested on several bodies of revolution. Linear approximation of a cylinder profile obtained by the prototype shows maximum approximation inconsistency of 15. The results are verified by those obtained by the conventional x-ray method.

The Progress in Photoacoustic and Laser Ultrasonic Tomographic Imaging for Biomedicine and Industry: A Review

“…If, however, the acoustic boundary is highly reflective, the travel-time can be estimated using dedicated time-delay estimation algorithms. In this case, the distance to the boundary can be found with much better accuracy than the size of LU PSF [52,53].…”

“…LUT was applied to the immersion ultrasound profilometry of solid samples [52,53], measurements of internal geometry of solid samples with complex external surface [54], inspection of thick welded joints [55], and evaluation of internal structure of rock samples [56] and biological objects [45,[57][58][59][60][61] (often in combination with PAT). These applications will be reviewed, in more detail, below.…”

Преобразование Данных Лазерной Ультразвуковой Томографии В Медицинский Формат DICOM

“…На текущий момент экспериментальные системы на основе оптико-акустической томографии только разрабатываются для различных биомедицинских задач (диагностика раковых заболеваний человека, исследование отдельных органов и томографии мелких животных) [18,19]. Участники проекта уже разработали методы применения ЛУ томографии для иммерсионной ультразвуковой профилометрии твердых объектов [20,21], измерений внутренней геометрии твердых образцов со сложной геометрией наружной поверхности [22], контроля толстых сварных соединений [23] и оценки внутренней структуры образцов горных пород [24]. ЛУ томография была применена для иммерсионных ультразвуковых исследований биологических объектов в работах [25][26][27] (часто в сочетании с ОА томографией).…”