Reflective fiber optic sensors for nondestructive monitoring of orange penicillin on ink stained paper artefact surfaces

In order to obtain the characteristics of orange penicillium growth on the surface of paper cultural relics, a reflective concave stepped oblique lens fiber optic sensor was developed. And in order to be more in line with the characteristics of paper artefacts, the paper artefacts were subjected to ink dyeing treatment. The sensor was used to monitor and analyse the growth process of Penicillium oryzae on the surface of ink-dyed cotton paper samples and burlap samples, and the structure and height of Penicillium oryzae biofilm were characterized by super depth-of-field microscope. The study shows that the sensor can accurately measure the biofilm height of the growth information of Penicillium oryzae on the surface of ink-dyed paper samples, and the output signal of the sensor has a linear relationship with the biofilm height of Penicillium oryzae.