Monthly Archives: June 2010

How an HID Prox Card Works

ISOPROX

A proximity card by HID is capable of storing embedded information inside. The information stored can be extracted and transmitted to a control system for processing. If the information transmitted lines up with the data stored in the control system, the system will provide an appropriate action, such as unlocking a door for a card holder.

The HID prox card, sized the same as your credit card, is part of a system that includes the cards, a card reader or readers, computer and an access control panel. Together, these components work together to act as a security officer in an organization to approve access to secure facilities or networks. Detailed, accurate reporting occurs with this system as the electronic devices log each transaction.

HID cards work as they carry an embedded binary code unique to the card holder. The code is referenced to the card holder in the database in the access system and is a specific sequence number that can be extracted by a card reader when swiped or held near the card reader.

The card reader connected to the access control system relays the sequencing for review when the card is held near. The control panel accepts the information and reviews it in a specific order to determine access eligibility. The data string is first reviewed for length. If that is correct, the binary code formatting is reviewed to determine if it can be recognized. With positive results, the system advances to review the facility code and the site code for positive matching results. If the card number is then confirmed in the database without restrictions on current time or location, the card holder is approved for access. The controller provides authorization to unlock the mechanisms restricting the door or network from opening.

The security personnel in charge of the software application have authorization to enter the database and update card holder information. Authorized people can configure the door access hardware to open and they can approve of the HID prox card entry at specific times. Reports for all activities can be generated as needed for management review.

Want to learn more about HID access cards and systems? Check out these links from our blog:

Using an HID card as an Identification Card

Tips for Printing on Your HID Card

Components of an Access System

Best Practices with HID Cards

Dye Sublimation Printing vs. Thermal Transfer Printing

Plastic ID card printers use two types of printing.  Thermal transfer printing and dye sublimation printing are used in both direct to card printers and retransfer printers.  Direct to card printers merge the image directly on the surface of the card.  Retransfer printing deposits the image on the back of a clear plastic film.  This film is then bonded to the surface of a plastic card.  Retransfer printing is the newest of these printing types and results in a better image result.  The card design is applied to specialized cards and does not require a perfectly smooth card as the direct to card printers require.

Thermal Transfer Printing

Thermal printing is when resin or ink is melted off of a printer ribbon and is directly transferred to the retransfer film or the surface of the card.  To melt the ink, a print head is used.  The print head has heated pins that are aligned across a ceramic plate.  In the correct sequence, the pins in the print head receive instructions to heat and release ink at just the right moment. The desired digital image created in the software is recreated on the card or ribbon.

Colored prints require the use of Y, M and C panels.  As each panel passes over the card, dots of color are released resulting in the completed image.  The K panel produces needed black printing on the card.  Dithering allows the dots of different colors to be placed close together to create a blended shade when observed.

Monochrome printing is also available.  This single color ribbon produces clear results with standard text and with bar codes.  Monochrome printing is completed at high speeds and is often used to customize a preprinted card.  The thermal ribbons provide durable print that resists fading. The resin dries quickly.

Dye Sublimation

Sublimation is when a solid is heated directly into a gaseous state.  The solid bypasses the liquid state during heating.  With this printing, the dye is heated to about 250 degrees Fahrenheit while the polymers in the PVC card are heated to 350 degrees.  The gaseous dye penetrates the plastic and as the card cools, the dye chemically bonds with the plastic card.

Crisp, sharp images are printed with dye sublimation printing.  Photographic images are printed with accuracy.  The higher heat levels allow more dye to be released into the card surface.  The result is the colors blend into a pleasing result as there is control over the opacity and transparency of the printing result.

Colors in this printing method are applied one panel at a time- the Y, M and C.  This type of print is prone to fading when exposed to UV rays from the sun.  Often a UV resistant topcoat is recommended to help protect the dye printed cards.