All about barcode scanners: classification, functions, characteristics. Differences between 1D and 2D barcode readers. Features of the use of wired and wireless scanners. Comprehensive automation with Bluetooth scanner and dedicated DataMobile software.
Barcode scanner – what is it: functions and application features
Barcode scanner – a device for reading identifiers of various formats. Recognizes codes on paper media: product packaging and labels applied to them. First of all, one-dimensional (1D) and two-dimensional (2D) barcode scanners are distinguished. 2D imagers are able to scan the ID from the display, smartphone and tablet. Specialized models recognize DPM (Direct Marking) codes, for example, on the surface of a component.
Scanners can be conditionally classified according to the following features:
- type of reading mechanism;
- scanning technologies;
- type of connection to external equipment;
- type of design, body design and areas of application.
The last classification is essential for business. We dedicated a separate post to it. Today we will talk about the first three.
1D and 2D barcode scanners: features and functions
Let's start with the types of reading elements. The key difference between scanner models is the ability to recognize barcodes of various symbols: 1D or 2D. The reader of 1D-identifiers may not be inferior in technical characteristics (for example, in range) to a 2D-imager, but it does not work with two-dimensional codes. And most importantly, it is not suitable for working with Data Matrix, which are released by Chestny ZNAK.
One-dimensional (1D) barcode scanners
They are divided into two subspecies – according to the mechanism of the reading element. Each of them has its own advantages and disadvantages.
LED
The mechanism of the reading module consists of two components: an LED emitter and a CCD matrix (charge-coupled device) – a microcircuit that does not include dynamic elements. The board is made of silicon and consists of photosensitive photodiodes. Functions as a charge-coupled device (CCD).
pros: strength, reliability and endurance. Relatively low cost.
Minuses: "can" read only 1D codes. They do not "see" identifiers on displays, screens of smartphones and tablets.
Laser
The basic mechanism is a system of mirrors that unfold the beam (as in a camera). Contains moving parts. Some models of laser readers have a shock-resistant design.
pros: high frequency and range of scanning.
Minuses: "afraid" of falling. They do not recognize 2D barcodes and do not “see” images on the screens of monitors, smartphones and tablets.
In turn, laser models differ in readout technology.
Single plane (linear)
A unidirectional stream of rays is formed, forming a narrow area of "vision". The scanning plane must coincide with the location of the product label (or box) on which the barcode is applied. That is, the object should be placed perpendicular to the window of the reading element.
Multiplanar
Beam grids are formed, and the light fluxes are multidirectional, and the number of "vision" bands depends on the model. It is not necessary to bring the reader window to the object in a special way – the device will automatically capture the barcode.
2D Barcode Scanners – 2D Imagers
Photo scanners. The mechanism is a miniature digital camera. It contains no moving parts. Devices recognize both 1D and 2D identifiers of any symbology. How does a QR code and 2D barcode scanner work? It does not form a light strip (or grid), but a "spot" – a plane, area or field of view. Captures a picture, photographing it – "makes" a copy. Almost all 2D imager models recognize any black and white images – signatures, photos, and others.
Matrix 2D imagers support the hardware decoding function – they “know how” to decipher the “photographed” identifier. Not all models are equipped with hardware decoders – some devices turn to software algorithms to extract data from the image.
pros: resistance to external influences and the presence of the function of reading images from the screens of monitors and mobile devices.
Minuses: 2D imagers are more expensive than 1D barcode scanners.
Other scanner features
In addition to the main – classifying – there are several more characteristics of scanning devices that directly affect their functionality.
Scanning frequency
This characteristic in many reviews is often replaced by "speed", which is not entirely true. It is expressed by the number of operations per second – scans (individual elements of the barcode) or lines (processing of fragments in the so-called "swath of view" is implied and is used when describing, as a rule, stationary models).
The characteristic "scanning speed" is not entirely correct. And that's why. The reader captures the elements of the barcode and combines them into a single (solid) image. Transfers a copy to a computer, mobile device or smart terminal. Conditional 500 scans (or lines) per second – the number of captures of areas of the same identifier. The operations are repeated until the reader assembles a complete “picture” from tiny photocopies that can be decoded. Thus, a more accurate definition is the frequency of scanning.
The more elements the scanner is able to process within a second, the faster it will “add” them and reproduce an image that can be decoded.
Note. 1D identifiers are processed faster than 2D ones, primarily due to the character structure.
Scanning range
The characteristic is so important that the manufacturers are often added to the "tail" model of the corresponding abbreviation. By it, you can determine which category applies to the scanning device:
- Sr. – Standard Range – up to 60 cm.
- Mr. – Middle Range – up to 1 m.
- LR – LONG RANGE – up to 10 m.
- ER – Extended Range – up to 16 m.
Impact resistance of the case
To protect the scanner from falling and extend its life, manufacturers strengthen the body and conduct a drop test of the experimental sample. The goal is to identify the number of tippers withstanding the model without loss of performance.
In the "Shockproof" section, the manufacturer indicates:
- number of permissible drops (or tipping);
- The maximum height from which you can drop the model;
- Surface type, such as concrete.
Advice. Impact resistance is not an absolute parameter. No warranty developer as a rule does not give. It should be understood: if the reader fails after falling, most likely you will have to repair it at your own expense.
Dust and moisture protection
IPxy index (International Protection Marking), where X is a dust indicator, and y – moisture resistance. Both are numeric. Maximum indicator – IP68. Protection of the case according to this standard means that the device is completely sealed and able to withstand immersion into water. The characteristic should be paid when choosing both industrial and warehouse models.
Built-in memory
Hardware addition characteristic of wireless models. The storage function of the assembled identifiers is important during warehouse work with a large number of nomenclatures. In memory of the device, you can burn up to several thousand barcodes, and then upright them at the PC base.