HiPA Solution – [Ghost Writer & Reader] Invisible 2D Barcode

subsurface 2d barcode marking and reading system
Table of Contents

Applications and Requirements

Two-dimensional barcodes have been widely used both industrial environment, as a production process tracking method, and in commercial environment, as a product identifier. As a process tracker, each work piece has its own barcode to be scanned at every station along the production line. This allows real-time yield tracking of the entire production process, which provides a data basis for the process improcement.  As a product identifier, the 2D barcode is also used for anti-counterfeiting and ensures the authenticity of products reaching end consumers. The invisible 2D barcode is marked with special laser-engraving equipment. The barcode is engraved inside the glass or sapphire material, which cannot be tampered with or removed. Different from visible barcodes, the invisible 2D barcode is not visible to human eye. It can only be read by certain barcode scanners. This quality can ensure no damage to the product cosmetics while keeping the whole production process traceability.

JPT provides subsurface 2D barcode solutions that can be applied in the following industries or fields:

subsurface 2d barcode solutions

Common 2D barcode/QR code marking methods are as follows:

1. Two-dimensional code marked in the glass ink area

qr code

2. QR code label

qr code label

Common invisible barcode marking method is as follows:

Comparison between invisible barcode and traditional barcode:

invisible barcode and traditional barcode comparison

The Principle of Marking

The brittle material subsurface 2D barcode solution provided by JPT uses an ultrafast laser, the principle of which is shown in the figure below. The ultrashort pulse laser energy passes through the transparent brittle material and is focused inside the material by the field mirror. Ultrafast laser acts in the materials in a very short time (0.2-0.5s) and in a very small area (0.1-0.5mm). The temperature of the material in the focus position (energy density above 106MW/mm2) rises sharply in an instant to form a plasma and then cools to form a modified region (ie code point, the diameter is in the order of microns). The light transmittance of the modified area is different from that of the other areas. Due to its extremely small size, it is invisible to the naked eye and must be read by a special code reading device.

how does beam forming code points inside the material
energy density distribution at the focal point
the position of the qr code inside the glass
jpt dedicated barcode reader
the shape of the code point inside the glass material

Product Highlights

  1. Invisible marking, invisible to the human eye, and no traces on the surface.
  2. It has little effect on the strength of the material, and can still pass the 3PB and ROR strength tests after coding.
  3. Fully customized code reading light source, optical system, and cutting-edge customized image processing algorithm.
  4. 100% code reading rate (sapphire, light glass, frosted glass).
  5. Online code depth measurement, which gives precise control of barcode depth.
  6. Real-time laser power monitoring.
  7. The code is still readable but invisible after applying ink and coating.
  8. The code marking and reading functions can be designed as independent or integrated as one solution.
  9. Customized automatic loading and unloading.

Equipment Parameters

equipment parameters

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