Laser Marking of ECC 200 2D Matrix Codes on Printed Circuit Boards
Brands of electronic equipment, from home audio gear to automotive keyless entry programs, are ever more in search of a trustworthy, cost-effective approach for uniquely figuring out and monitoring merchandise from the manufacturing cycle, product sales distribution and just after-sale guarantee verification. An autonomous, automatic monitoring technique calls for that a long term, machine-readable code be placed on an internal printed circuit board to uniquely detect Every single solution. The code needs to be durable adequate to outlive manufacturing processes together with wave solder and board cleansing, need to not have an impact on circuit overall performance, and should shop data while in the tiny space out there on real-estate aware printed circuit boards.
The 2D matrix code supplies a method to retailer alphanumeric character strings in quite little regions of the printed circuit board. Laser marking know-how delivers a way for completely making use of second matrix codes to most board substrates. The high-resolution and substantial-accuracy of beam-steered laser marking devices supplies the implies to make nicely outlined, large trustworthiness codes no matter code measurement. Laser marking also offers the user with a pc-managed marking course of action for easy implementation into automatic solution tracking methods.
ECC 200 2D Matrix Codes
Two-dimensional symbologies encode details in the shape of the checkerboard pattern of on/off cells. Particular advantages of Info Matrix codes about standard 1D barcodes consist of:
Encode information digitally, instead of the analog encoding of information in typical barcodes.
Can accommodate lower-distinction printing instantly on sections with out demanding a label
Offer extremely superior details density – the highest among the other widespread 2D codes, which implies which you could put a great deal of data in an exceptionally small spot.
They may be scaleable, which means that you could print them and browse them in different amounts of magnification – only limited by the resolution of your obtainable printing and imaging methods.
Because of the substantial information density inherent to Info Matrix codes, Additionally they offer constructed-in error-correction methods which permit completely recovering the message encoded in an information Matrix image even when the mark is weakened and lacking around twenty% from the image.
They may be browse by video clip cameras versus a scanned laser beam employed for examining typical barcodes, which suggests that they can be browse in almost any orientation.
ECC two hundred Info Matrix is the most popular 2-D symbology with intensive use in automotive, aerospace, electronics, semiconductor, healthcare units and other producing device-amount traceability purposes. Data Matrix codes are generally not changing regular linear barcodes, but are being used the place standard barcodes ended up too large, did not deliver enough storage potential, or have been unreadable.
Facts Matrix Code Structure
The second matrix codes look as being a “checkerboard” with the person squares (cells) in possibly on on (white) or off (black) condition. The code is composed of four distinctive components.
The Finder “L” Pattern contains a stable row of cells alongside the left edge and base of the code that orients the reader towards the structure pharmaceutical translation services with the 2D code.
The Clock Monitor is often a sequence of on/off cells alongside the right edge and best on the code that designates the row/column count for the reader.
The info Location is definitely the sample of black and white cells throughout the L sample and also the clock tracks that incorporate the alphanumeric written content from the code.
The Peaceful Zone within the code has to be free of any functions that may be obvious for the reader. The tranquil zone needs to be a minimum of two rows/columns extensive for codes created of sq. cells. The quiet zone should be at the very least 4 rows/columns extensive for codes produced of circular cells (dots).
ECC two hundred Details Matrix codes can retail store nearly 3,116 numeric, two,335 alphanumeric characters or one,555 bytes of binary data inside of a a hundred and forty four column by 144 row array. Extra practical image Proportions for printed circuit boards can however have a big quantity of data.
Laser Marking Procedure
The laser marking process consists of the laser source, the beam-shaping optics, and also the beam-steering program.
The laser is a lightweight amplifier building a brilliant, collimated beam of light at a specific wavelength. For FR4 and solder mask applications, most buyers select the air-cooled CO2 laser operating at The ten,640nm much-infrared wavelength. This laser offers numerous general performance and price pros, and generates superb marking final results.
The laser beam is projected by two beam-deflecting mirrors mounted to high-speed, substantial-precision galvanometers. Because the mirrors are rotated less than route on the system Pc, the laser beam scans through the concentrate on marking surface to “draw” the desired marking graphic.
After the laser beam is deflected from your beam-steering mirrors, it is concentrated into the smallest spot probable by flat-subject focusing optics. The flat-area focusing assembly is really a multi-component optical gadget built to maintain the focal airplane with the centered laser beam on a relatively flat aircraft through the entire marking subject. The focused laser light appreciably raises the electrical power density and involved marking electric power.
The purpose of the laser optical teach is usually to concentration the laser beam to a little location and also to scan the laser beam in excess of the focus on surface with substantial pace and accuracy. While using the CO2 laser configuration, the centered spot diameter and related marking line width is about 0.0035″ to 0.004″. Man-readable textual content characters can be as tiny as 0.040″ and second matrix codes is usually created from person attributes as modest as just one 0.004″ dot.
PCB Marking
To mark printed circuit boards, the warmth produced because of the laser beam thermally alters the surface area on the board to make a contrasting, legible mark. The process isn't going to demand labels, stencils, punches or any other auxiliary hardware or consumable.
For printed circuit board programs, a number of distinctive variations of This system can be employed for different board/coating supplies and qualifications situations.
Solder mask or other Conformal Coatings on FR4 Boards –
The laser beam can alter the texture of your coating, offering it a lighter contrasting visual appeal, or can fully eliminate the coating to show the underlying substrate or copper floor aircraft.
Uncoated FR4 –
The laser beam alters the feel from the surface with the FR4 manufacturing a near white overall look.
Silk-screened Ink Block –
For consumers who by now silkscreen part identification or other preset information on the boards, a silk-screened white ink block can purpose for document translation services a history on the second matrix code to optimize readability. This system is especially helpful when
o The background coloration with the board is similar to the colour with the laser mark.
o Underlying circuitry would obscure the marking graphic to code audience.
o The board product isn't appropriate for laser marking, for instance ceramic substrates.
2nd Matrix Code Verification
Verification of your legibility and written content in the 2D matrix codes is a vital phase in the general high-quality software. After marking of every circuit, the reader verifies the integrity from the mark in advance of indexing the laser marking head to the subsequent marking location. The reader retrieves the alphanumeric text string through the 2nd code and compares it Together with the textual content string which was for being marked.
The reader also evaluates the legibility from the code determined by several different parameters which includes foreground/qualifications distinction, geometric precision (skew, squareness, and many others.) along with the dimensional precision of both of those the marked and unmarked cells. The 2nd matrix codes are then classified as handed (eco-friendly), warned (yellow) or failed (red). For All round manufacturing efficiency, the laser method might be programmed to confirm merely a select handful of second codes on the panel, then to instantly swap to verifying each individual code if the code legibility falls underneath a specified degree.
Nowadays’s audience do an excellent occupation looking at lower distinction second codes. In case the laser marking process is set up on an assembly line with older second matrix visitors downstream from the laser marker, the verification reader could be configured to evaluate the codes according to the overall performance in the older downstream audience to guarantee constant efficiency all through the assembly system.
Marking Functionality
The typical printed circuit board marker is a totally automatic, SMEMA-compliant, by-conveyor laser marking technique. The general productivity on the laser marker is comprised of several ways which make up the marking cycle. The steps required to mark 1 multi-array panel are
1. Transportation and positioning from the panel while in the marking spot.
2. Fiducial place detection (optional)
3. Marking of the primary circuit while in the array
four. Verification in the marked 2D matrix code (optional)
five. Movement of your laser marking head to another circuit inside the array.
6. Repeat measures three and four for the remaining circuits while in the array.
seven. Transport from the panel out on the laser marking program (synonymous with bringing the following panel in)
Price of Operation
Cost of Procedure is significantly less than $1.00 per hour. Regular utilities necessities are 110VAC, 1-stage, 12A. A compressed air source is required for the pneumatics. Total utilities costs at optimum laser electrical power (the laser really should really operate at much less then eighty% rated ability) are $0.twelve per hour. The key consumable product could be the CO2 laser tube that need to be replaced every single three to 5 years in a cost of normally $1,000.00 to $one,five hundred.00. Assuming a 40-hour workweek and tube lifetime of three years, the tube substitute Value would equate to $0.18 for each hour for a complete functioning expense of $0.thirty per hour under worst situation circumstances. Actual operating fees will probably be reduce due to lower than optimum electrical use and more time tube lifetime.
For typical pcb laser marking programs, the expense for marking is fewer than $0.0003 per circuit.
Summary
The electronics industry is searching for a value and technically efficient usually means of making use of equipment-readable codes to printed circuit boards Considering that the 1980’s. Early attempts included laser marking linear barcodes about the board edge, a daunting obstacle for reader alignment, and marking linear barcodes close to circuit traces, also a challenge for barcode viewers. Barcode material was limited to a couple of figures as a result of constrained House as well as the barcodes character-for each-inch capability.
The event with the second matrix code combined with the resolution, permanence and velocity of beam-steered laser marking technology now delivers brands a responsible, cost-helpful, adaptable and verifiable indicates to uniquely establish every single merchandise through production, distribution and immediately after-sale.