Why Do Barcode Scanners Use Red Light?

Why Do Barcode Scanners Use Red Light

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Barcode scanning has become an integral part of many businesses nowadays. It is a convenient method of capturing the information needed for business operations like inventory management, sales tracking, and other processes. 

While barcode scanners come in a variety of shapes and sizes, one thing that they all have in common is the use of red light. In this blog post, we will discuss the reasons behind the use of red lights in barcode scanning technology. 

The Science Behind Red Light

To understand why red light is used in barcode scanners, we must first understand the electromagnetic spectrum. 

The electromagnetic spectrum is the range of all types of electromagnetic radiation. The spectrum contains the following radiations. 

  1. Radio waves
  2. Microwaves
  3. Infrared
  4. Visible light
  5. Ultraviolet
  6. X-rays
  7. Gamma rays

Visible light is a small part of the spectrum, with wavelengths ranging from 400 to 750 nanometers. Within the visible light spectrum, there are different colours with different wavelengths, including. 

620 – 750 nm
590 – 625 nm
565 – 590 nm
520 – 565 nm
500 – 520 nm
435 – 500 nm
380 – 450 nm

Red light has the longest wavelength compared to other colours. The longer wavelength makes it perfect for barcode scanning because it can penetrate deeper into the barcode and extract more information. Red light also scatters less, resulting in more accurate scans.

Advantages of Red Light in Barcode Scanners

Three advantages of Red light

Increased Accuracy

Red light in barcode scanners increases scan accuracy. Because red light penetrates further into the barcode, it can capture more data and produce a more accurate scan. This is especially true when scanning smaller barcodes or ones with high information density.

Improve Readability

Red light improves readability. It is less likely to cause glare or reflections than other light colours, making it easier to read barcodes in bright or low-light environments.

Reduces Strain on the Eyes

Red light reduces strain on the eyes. Red light is less harsh on the eyes than blue or green light, which can cause eye fatigue over time. This is especially important for workers who use barcode scanners for extended periods of time.

Alternatives to Red Light

Besides red light, other colours can be used in barcode readers.

Green and blue lights are also used in barcode scanners but come with caveats. Green light is more expensive and energy-intensive. In comparison, blue light is not compatible with some barcode types, is intense, costly and causes eye sensitivity. 

Yellow light was also tried in barcode scanning but was less effective than red or green at providing contrast. The shorter wavelength of yellow makes it difficult to scan barcodes from a distance. 

Other colours, such as cyan, blue and violet, have short wavelengths and hence are never used for barcode scanning.

Frequently Asked Questions

Does the Barcode Colour Affect the Scanner's Light Colour?

No, the barcode colour does not affect the scanner’s light colour. Barcode scanners emit a specific wavelength of light regardless of the barcode colour.

What are Some Common Applications of Barcode Scanners With Red Lights?

Barcode scanners with red lights are commonly found in the retail, healthcare, and manufacturing industries.

In retail, they scan products at the point of sale.

Healthcare uses them to track medical supplies and equipment.

Manufacturing uses them to manage inventory and the supply chain.

The Bottom Line

In conclusion, barcode scanners use red light because it is the most visible and efficient colour for scanning barcodes. The use of red light enhances readability, accuracy, and precision while providing a safe and comfortable scanning experience.

As barcode technology continues to evolve, new lighting options may emerge, but for now, red light remains the gold standard for barcode scanning. We hope this article answered your question about why barcode scanners use red lights.

Thanks for reading!

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