Passport Scanning: Airport Security's Inner Workings

Passport scanners are advanced devices that use a variety of technologies to accurately read and verify the information contained in passports and other travel documents. The process involves capturing high-resolution images of the passport page, extracting data from chips and barcodes, and verifying security features to ensure the document's authenticity. This enables border control authorities to confirm the traveller's identity and ensure the security of their destination country. The data extracted from passports is also shared with the destination country and may be stored in databases for decades.

Passport scanners use UV light to reveal security features like UV-visible inks

Passport scanners use ultraviolet (UV) light to reveal security features such as UV-visible inks and holograms. These security features are invisible to the naked eye under regular light conditions but become visible when illuminated by UV light. This technology is crucial for detecting forgeries or alterations to the passport.

UV-visible inks are used in passports to embed critical information, such as serial numbers or special patterns, that can only be revealed under UV light. This serves as an effective security measure, making it challenging for potential forgers to replicate the passport. The UV-visible inks add an extra layer of protection to the passport, working in conjunction with other security features.

One notable aspect of UV-visible inks is their ability to change colour and appearance as the angle of illumination changes. This feature is known as optically variable ink or Optically Variable Device (OVD). OVDs create a three-dimensional effect, enhancing the security of the passport. The use of OVDs adds complexity and makes it exceptionally difficult for forgers to replicate the intricate optical characteristics.

Additionally, passports may be printed on special paper known as UV-dull paper. This type of paper is designed to not reflect ultraviolet light, ensuring that the UV ink remains invisible under regular light conditions. When a UV light is shone on a document printed on UV-dull paper, it should exhibit a dark blue-purple colour. If the paper does not react to UV light, turning white instead, it indicates a potential forgery.

The combination of UV-visible inks and UV-dull paper in passports creates a robust defence against counterfeiting and tampering. By leveraging UV light technology, passport scanners can reveal these hidden security features, ensuring the authenticity and integrity of travel documents worldwide.

Infrared imaging verifies features only visible under infrared light

Passport scanners are sophisticated devices that incorporate multiple technologies to accurately read and verify the information contained in passports and other travel documents. One of the key technologies employed by these scanners is infrared (IR) imaging.

Infrared imaging is used to verify security features that are only visible under infrared light. This helps in the detection of forged or altered passports. By utilizing infrared light, the scanner can reveal details that are not visible to the human eye or with standard imaging technologies.

Infrared imaging takes advantage of the fact that certain materials have different reflectance and absorption properties when exposed to infrared light. This results in the ability to detect features that may be hidden or invisible under normal visible light conditions.

To achieve this, specialized IR cameras or sensors are used. These cameras are often modified to remove IR-cut filters, allowing them to capture infrared light. The removal of these filters enhances the camera's sensitivity to infrared radiation, enabling the detection of subtle details.

Additionally, infrared imaging systems can employ specific infrared filters, such as Kodak Wratten IR filters, to fine-tune the camera's sensitivity to particular wavelengths within the infrared spectrum. This flexibility allows for the optimization of the imaging system based on the specific security features being verified.

Optical Character Recognition (OCR) turns printed characters into digital data

Optical Character Recognition (OCR) is a technology that turns printed characters into digital data. It is a crucial component of passport scanners, enabling the extraction of text from the Machine Readable Zone (MRZ) of passports and other travel documents.

The MRZ typically includes essential information such as the passport number, name, nationality, date of birth, and expiration date. By using OCR, the scanner can decipher the printed characters within the MRZ and convert them into a digital format that the system can process and understand.

This digital data is then utilised to verify the document's validity and identify any discrepancies or anomalies. For instance, the system can cross-reference the printed information with the data stored in the passport's chip, ensuring that they match. Additionally, the digital data can be compared against various databases to check if the passport holder is on any watchlists or has any visa or travel history records.

OCR technology plays a vital role in enhancing the accuracy and efficiency of passport scanning processes at airport checkpoints. It enables the automated verification of travel documents, streamlining the identification and security checks for travellers.

Radio-Frequency Identification (RFID) chip data is captured

Radio-Frequency Identification (RFID) is a technology that uses electromagnetic fields to identify and track tags containing electronically stored information. These tags are tiny computer chips with antennas that can be affixed to objects, such as passports, to enable wireless data transmission when prompted by a reader.

RFID technology is used in passports to enhance security and expedite the identification and verification process at border checkpoints. The RFID chip in a passport stores crucial biographical data, including the passport holder's name, nationality, date of birth, passport number, expiration date, and a digital photograph. This chip is embedded in the passport and can be read by specialised scanners, which are a part of the Automated Border Control (ABC) system.

When a passport with an RFID chip is scanned, the chip broadcasts specific information to immigration authorities. This information is crucial for identity verification and ensuring the security of the destination country. The data transmitted by the RFID chip is protected by encryption and digital signatures, ensuring that only authorised individuals with the correct secret key can access or modify the information.

Additionally, the RFID chip data is cross-referenced with other security features in the passport, such as the Machine Readable Zone (MRZ), to ensure the integrity of the document. This multi-layered security approach helps to prevent forgery and tampering, as any discrepancies between the RFID data and other sources will be flagged by the system.

Data is cross-verified across different readings

Passport scanners are advanced devices that use multiple technologies to accurately read and verify the information in passports and other travel documents. The data verification process involves cross-referencing information across different readings to ensure accuracy and identify any discrepancies.

Passport scanners employ Optical Character Recognition (OCR) technology to extract printed text from passports. OCR is used to read the Machine Readable Zone (MRZ) of the passport, which contains crucial information such as the passport number, name, nationality, date of birth, and expiration date. By using OCR, the scanner can convert the scanned image into machine-readable text, facilitating data extraction and verification.

Additionally, passport scanners can read information from RFID chips embedded in passports. These chips contain biographical data, digital photographs, and other information, such as the passport number and expiration date. The data extracted from the RFID chip is cross-verified with the information obtained from the MRZ. This cross-verification ensures the consistency of the data and helps detect potential forgeries or alterations to the passport.

The scanner also captures high-resolution images of the passport using multiple wavelengths of light, including ultraviolet (UV) and infrared (IR) imaging. These images are used to expose both visible and invisible security features, such as UV-visible inks and holograms. By comparing the printed information with the data stored in the chip, the scanner can identify any discrepancies and enhance the accuracy of the verification process.

Furthermore, passport scanners are often integrated with national and international databases. This integration allows for real-time verification against watchlists, visa records, and travel history. The scanned passport data is cross-referenced with these databases to ensure the information provided by the traveller is accurate and up-to-date. This cross-verification across different systems helps maintain security and facilitate smooth border crossings.

Frequently asked questions