Secure Quick Response codes or SQR codes are secure high data density two dimensional bar-codes. QR codes are high density 2D bar codes first created and patented by Denso Wave in Japan QR codes. They are becoming a popular means to encode data for quick machine readable (camera or bar-code scanner)retrieval and decoding on a worldwide basis. Nokia, Apple, and Android smart-phones often already have a mobile application to create and read QR codes and there are numerous mobile application available which can be downloaded from application stores.
Secure Quick Response codes are as the name implies a secure method for encrypting data into a bar-code which then becomes extremely difficult to decode into the original plain text in the absence of the encryption cipher or key. A typical implementation of SQR codes would be to create a one-time use SQR code on a mobile handset's high resolution screen to effectively create a highly secure one-time-pad type of encryption One Time Pad of for example an on-line account number. SQR codes because they can be used on hundreds of millions of already installed phones and because no additional hardware on the mobile handset is necessary, can operate in a similar fashion to NFC handsets for secure mobile payments. A typical implementation is to encrypt and use a precursor physical machine readable token such as the card identity number (CID) written in read-only-memory (ROM) of a Secure Digital microSD card contained in a mobile telephone or even the international mobile identity number (IMEI) IMEI in the event no microSD card is present as for example on an Apple iPhone. SQR codes may be securely machine read in a retail environment at the POS using prevalent 2D bar-code scanners or even a low cost web camera. Secure Quick Response codes were first developed by Yodo a company operating in Japan and are patent pending.