Fig. 1. Schematic representation of circular film

Fig. 2. Schematic of digital holographic endoscopy interference light path

Fig. 3. Simulation results of first-order vibration modes of perforated films. (a) Defect-free film; (b) film with a 3 mm diameter perforation in the center; (c) film with a 5 mm diameter perforation in the center; (d) film with an eccentric 3 mm diameter perforation; (e) film with an eccentric 5 mm diameter perforation

Fig. 4. Section of amplitude at y=0. (a) Central perforated film; (b) eccentric perforated film

Fig. 5. Simulation results of first-order vibration modes of scratched films. (a) Film with a 3 mm scratch in the center; (b) film with a 6 mm scratch in the center; (c) film with an eccentric 3 mm scratch; (d) film with an eccentric 6 mm scratch

Fig. 6. Section of amplitude of scratched films. (a) Section at y=0.1 of the centrally scratched film; (b) section at y=-3.7 of the eccentrically scratched film

Fig. 7. Simulation results of first-order vibration modes of calcified films. (a) Schematic of calcified film; (b)-(e) films with calcification thickness of 0.1, 0.2, 0.3 and 0.4 mm, respectively

Fig. 8. Section of amplitude at x=0

Fig. 9. Experimental device for out-of-plane deformation detection. (a) Optical path system; (b) J0900D endoscopic otoscope; (c) sample fixture; (d) sound generator

Fig. 10. First-order vibrational mode diagram of a defect-free film

Fig. 11. First-order vibrational mode diagrams of perforated films. (a) Film with a 3 mm diameter perforation in the center; (b) film with a 5 mm diameter perforation in the center; (c) film with an eccentric 3 mm diameter perforation; (d) film with an eccentric 5 mm diameter perforation

Fig. 12. First-order vibrational mode diagrams of scratched films. (a) Film with a 3 mm scratch in the center; (b) film with a 6 mm scratch in the center; (c) film with an eccentric 3 mm scratch; (d) film with an eccentric 6 mm scratch

Fig. 13. First-order vibrational mode diagrams of calcified films. (a) Film with calcification thickness of 0.1 mm; (b) film with calcification thickness of 0.3 mm