Speckle pattern analysis of security holograms and related foils for quality assessment and authentication.

Krishnan S., Keerthy; Ambadiyil, Sajan; Jha, Avinash Kumar; Prabhu, Radhakrishna

Abstract

A speckle pattern is produced by the mutual interference of a set of coherent wavefronts. Speckle patterns typically occur in diffuse reflections of monochromatic light such a laser light. When a rough surface is illuminated by a coherent light is imaged, a speckle pattern is observed in the image plane. This study involves the quality assessment and authentication of security holograms and its related foils by analyzing the speckle pattern generated from the specimen itself. Speckle pattern from various type of security holograms and foils are taken. By processing the image of the speckle pattern, the size of the speckles is analyzed using MATLAB software. By evaluating the size of the speckle generated, the feasibility of analyzing the quality and authenticity of the security hologram is assessed. The paper discusses about the experimental setup, image capturing, and processing method and the result obtained in detail.

Citation

KRISHNAN S., K., AMBADIYIL, S., JHA, A.K. and PRABHU, R. 2022. Speckle pattern analysis of security holograms and related foils for quality assessment and authentication. In Bouma, H., Prabhu, R., Stokes, R.J. and Yitzhaky, Y. (eds.) Counterterrorism, crime fighting, forensics, and surveillance technologies VI: proceedings of the 6th Counterterrorism, crime fighting, forensics, and surveillance technologies, co-located with SPIE (Society of Photo-optical Instrumentation Engineers) Security + defence conference 2022, 5-6 September 2022, Berlin, Germany. Proceedings of SPIE, 12275. Bellingham, WA: SPIE [online], article 1227509. Available from: https://doi.org/10.1117/12.2635446

• Conference Name: 6th Counterterrorism, crime fighting, forensics, and surveillance technologies, co-located with the 2022 SPIE Security + defence conference
• Conference Location: Berlin, Germany
• Start Date: Sep 5, 2022
• End Date: Sep 8, 2022
• Acceptance Date: Apr 6, 2022
• Online Publication Date: Sep 6, 2022
• Publication Date: Oct 28, 2022
• Deposit Date: Jan 19, 2023
• Publicly Available Date: Jan 19, 2023
• Publisher: Society of Photo-optical Instrumentation Engineers
• Series Title: Proceedings of SPIE
• Series Number: 12275
• Series ISSN: 0277-786X ; 1996-756X
• Book Title: Counterterrorism, crime fighting, forensics, and surveillance technologies VI
• ISBN: 9781510655539
• DOI: https://doi.org/10.1117/12.2635446
• Keywords: Speckle pattern; Security holograms; Security holograms; Foils; MATLAB software
• Public URL: https://rgu-repository.worktribe.com/output/1854464