This research is in the field of document security and the investigation of existing security devices. Security documents can be of two types; those that have commercial value, namely currency, articles of value and those that have legal value, namely, passports, identification cards etc. It is of vital importance in today's world, where fraud and counterfeiting are the order of the day, to protect any article or document of aesthetic importance and value. After the tragic events of September 11th 2001, security and the lack of security in every sense of the word is a much talked and researched subject. The literature review in Chapter Two will reveal that there are many security devices being currently used for various applications and each of them has many advantages and disadvantages. Devices such as magnetic cards, chip cards, biometric technology, optically variable devices, holograms and kinegrams and others have been described and their uses explained. Chapter Three is a continuation of literature review on Digital Watermarking and the available Digimarc technologies and applications in the field of security. Digimarc Corporation, based in Tualatin, Oregon, United States has been the pioneer in the field of Digital Watermarking. Microbar Security Limited, a subsidiary company of Durand Technology Limited, based at the Shrivenam 100 Business Park, Shrivenam, Oxfordshire, United Kingdom has developed its own watermarking technique, which has many advantages in comparison to the Digimarc Technology has also been described here.In Chapter Four, an optical variable device, namely, the Lippmann Optical Variable Device, named after the nineteenth century scientist Gabriel Lippmann (1845-1921), has been studied in thorough detail. Much work has been done to prove it and to understand the principle behind the theory he proposed. Currently, this type of technique based on interferential photography can be applied as a unique security device on passports, identification cards etc. The principles and theory of Lippmann photography has been explained in considerable detail. Experimental work done using various methods and using different photographic materials has also been described along with the results obtained. The application that has been emphasized here, is for passports for which this research was conducted in collaboration with Holographic Dimensions, Florida. Chapter Five, explains the principle of Covert Bar Coding which is the basis of the Microbar Watermarking Technique. Experimental results have been presented, these have been obtained using the MATLAB software. Finally, Chapter Six gives some ideas that can be pursued for future work. This work has produced two papers on Lippmann Photography and the mathematical evaluation of the emulsion co-authored by the author of the thesis. Abstracts from the papers have been used in this thesis. Also, it has produced two patents, one by `Holographic Dimensions', Florida on the Lippmann Photography and second, `Microbar Security Limited' on the `Covert Bar Coding Technique'.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:548835 |
| Date | January 2003 |
| Creators | de Souza, Savita |
| Publisher | De Montfort University |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://hdl.handle.net/2086/5847 |
Page generated in 0.1174 seconds