Abstract:
Infrared digital holography has strong real-time performance, is not easily disturbed by visible light, and can be detected in complex environments. It is widely used in special fields. For example, dust aerosols in a blasting environment have strong absorption and scattering effects on visible light, and infrared light at the wavelength of the "atmospheric window" in the infrared band is less affected by aerosols. This advantage has been combined with digital holography. A smooth cement plate of moderate size was fixed on a three-dimensional force application frame as the research object, and the infrared digital holography method was used to change the dust concentration in the environment. The stress field changes of smooth cement plates under different pressures were measured, and the feasibility of this method was verified by comparing holograms and phase differences. Visible light digital holography was used as a control experiment. The results show that infrared digital holography can measure the force application point, relative pressure, and stress influence area of the stress field in an environment of high-concentration dust and realize real-time, nondestructive, and full-field detection, while visible digital holography in this environment is poor or even unable to complete the detection. The method proposed in this paper significantly expands the practicality of the stress detection method based on digital holographic interferometry.