Over the span of decades, various barcode technologies have emerged to suit the tracking needs of various industries and applications—all of these technologies can be put into one of two categories:
Here we’re going to break down the basics of linear and 2D barcodes—what are they? How do you know which kind to use? How can both technologies be used together?
Let’s start with linear barcodes:
What are Linear Barcodes?
Linear barcodes are made up of a series of either horizontal or vertical lines—and are probably what immediately comes to mind when you think of a barcode.
Encoded in these lines (and sometimes the spaces as well) is data—generally related to identification, but you probably already know this if you’re using barcodes.
If you ever pay close attention to linear barcodes, you’ll notice they vary quite a bit—this is not only because each code is unique, but because there are various symbologies.
Each symbology is designed with a specific task in mind, making different types of codes suitable to different applications. For example, some linear barcodes encode only numerical data, while others encode both numbers and letters.
Linear barcodes can use either a continuous code or a discrete code. A continuous code contains data in both the bars and spaces. In a discrete code, the characters stand by themselves, requiring extra space between each adjacent character—making them less space efficient than continuous codes.
Here are a few examples of linear code symbologies:
- Code 25, also called 2 of 5
- Code 128
- Code 93
- Code 39
- Code 11
When to Use Linear Barcodes?
There’s a good reason you see linear barcodes so frequently—whether you’re in the lab, or out doing your weekly shopping.
Having been widely used for decades, there are a wide array of linear barcode symbologies suited to an array of applications—it’s unlikely you’ll run into a situation where a linear barcode won’t cut it.
Linear barcodes are also capable of being read by just about any scanner—new or old, inexpensive or technologically advanced. This is due in part to their popularity, and in part because they’ve been around for so long.
When it comes to specific symbologies, you’ll need to work with your supplier to make an informed decision. Your application and data needs must be taken into account to ensure success.
For example, you and your supplier will need to be familiar with industry barcoding standards—products of human origin, such as blood, are regulated by the ISBT 128 standard to increase accuracy and provide global traceability. Other standards exist for similar reasons as well.
Additionally, the shape and size of your labware may impact your barcode needs—microwell plates require a long and thin label and your symbology will need to be compatible with those labels.
What are 2D Barcodes?
2D barcodes can hold more data because they make use of both the horizontal and vertical dimensions. In a stacked barcode format, rows of linear symbols sit on top of one another—in a matrix format the bars and spaces form a checkerboard like pattern.
Matrix type 2D barcodes can encode between 1 and 2,000 characters! That’s pretty impressive, so if you need a lot of data on a small barcode label 2D barcodes are ideal.
Older scanners can read stacked 2D barcodes—since they are made up of several linear codes. Other types of 2D barcodes will require an imager type scanner, which thankfully have become fairly standard.
Here are a few examples of 2D barcode symbologies:
- Stacked—i.e. code 49
- QR code
- Data Matrix
When to Use 2D Barcodes?
As we already mentioned, if you have limited surface area for a barcode and a lot of data to encode, 2D barcodes are going to be a great solution.
Their ability to hold large amounts of data in a compact code makes them especially useful for small applications, such as on the bottoms and caps of tubes and vials.
Matrix style 2D codes are also capable of being read by smartphones and leading the smartphone user to a specific webpage. This can be extremely useful if you need to deliver paper waste-free information to an end-user who probably doesn’t have a barcode scanner on hand.
As with linear barcodes, when it comes down to choosing the right symbology it will depend on your data storage needs and applications, so we always recommend consulting an expert.
Using Linear and 2D Barcodes Together
Since linear barcodes can be read by all kinds of scanners, many businesses that use automation in their workflows prefer to have a linear code in at least one area.
For example, labs with automated workflows may leverage a linear barcode label on the side of a container and a 2D barcode on the bottom of the container to ensure readability throughout their entire process.
Both barcodes would contain the same information, but different scanners read the barcodes at different points in the workflow.
Using two barcodes is also a good way to insure your data in case one of the codes is damaged or becomes unreadable.Read our
Now that you know a little bit more about the difference between linear and 2D barcodes, your barcode supplier’s recommendations may make more sense, and you should be able to more confidently make build a barcode strategy suited to your lab.
The right barcode technology—or combination of technologies—should enhance your workflows and precisely match your labelling needs.