title: Perspectives of mid-infrared optical coherence tomography for inspection and micrometrology of industrial ceramics.
abstract: Optical coherence tomography (OCT) is a promising tool for detecting micro channels, metal prints, defects and delaminations embedded in alumina and zirconia ceramic layers at hundreds of micrometers beneath surfaces. The effect of surface roughness and scattering of probing radiation within sample on OCT inspection is analyzed from the experimental and simulated OCT images of the ceramic samples with varying surface roughnesses and operating wavelengths. By Monte Carlo simulations of the OCT images in the mid-IR the optimal operating wavelength is found to be 4 µm for the alumina samples and 2 µm for the zirconia samples for achieving sufficient probing depth of about 1 mm. The effects of rough surfaces and dispersion on the detection of the embedded boundaries are discussed. Two types of image artefacts are found in OCT images due to multiple reflections between neighboring boundaries and inhomogeneity of refractive index.
authors: Rong
authors: R
authors: Su
authors: Mikhail
authors: M
authors: Kirillin
authors: Ernest W
authors: EW
authors: Chang
authors: Ekaterina
authors: E
authors: Sergeeva
authors: Seok H
authors: SH
authors: Yun
authors: Lars
authors: L
authors: Mattsson
mesh_terms: D000465:Algorithms; D016477:Artifacts; D002516:Ceramics / Q000737:chemistry*; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008027:Light; D009010:Monte Carlo Method; D012031:Refractometry / Q000379:methods*; D012542:Scattering, Radiation; D041623:Tomography, Optical Coherence / Q000379:methods*