Can Laser Safety Glasses Protect Against Far-Infrared Radiation?

With the continuous advancement of science and technology, laser technology is increasingly used in industrial processing, teaching and scientific research, medical and other fields. Especially in environments where high-power lasers are used, laser safety glasses are essential protective equipment. They are designed to block or absorb lasers of specific wavelengths to protect the eyes from laser radiation. But at the same time, an important question arises - can laser safety glasses protect against far-infrared (FIR) radiation? This article explores the relationship between laser safety glasses and far-infrared protection, as well as the safety knowledge that users need to know.

1. What is far-infrared radiation?

Far-infrared radiation is a type of electromagnetic radiation with a wavelength typically between 15 μm and 1,000 μm (15,000 nm and 1,000,000 nm). It is beyond the range of visible and near-infrared light and is commonly used in: thermal imaging, heating devices, medical treatment equipment, industrial drying and curing systems.

While far infrared (FIR) is non-ionizing and generally less hazardous than UV or high-powered visible lasers, prolonged exposure to FIR can still cause eye or skin discomfort or thermal damage in some cases.

Lasers, on the other hand, are coherent, monochromatic (single wavelength) light sources. They emit concentrated energy at a specific wavelength, ranging from ultraviolet (UV) to visible light to infrared (IR). Laser safety glasses are designed to block lasers of a specific wavelength—for example, laser safety glasses designed for red lasers (approximately 650 nm) will not necessarily block green lasers (532 nm).Our LP-RHP laser safety glasses (620 - 700nm OD 4+) from LaserPair do not block 532nm green lasers.

2. Are laser safety glasses designed for FIR protection?

In short: not all laser safety glasses protect against FIR radiation. Their effectiveness depends on the wavelength range they are rated to block.

Key factors:

① Wavelength protection range

Laser safety glasses are rated for protection at specific wavelengths, such as 532 nm, 808 nm, or 1064 nm. If the glasses are not rated for protection beyond 10,000 nm, they will not effectively block far infrared radiation.

② Optical density (OD)

The OD value indicates how much light is attenuated even if the wavelength is covered. To provide far infrared (FIR) protection, the glasses must have a high OD value at far infrared wavelengths.

③ Material composition

Most laser glasses are made of polycarbonate or glass filters that are tuned for visible or near infrared bands. To block far infrared (FIR), special materials such as coated infrared reflective lenses or ceramic filters may be required.

3. When is far infrared (FIR) protection needed?

You may need specialized far-infrared (FIR) protective eyewear if you use the following equipment:

Carbon dioxide (CO₂) lasers (10,600 nm)

Infrared heaters and emitters

Medical far-infrared (FIR) therapy devices

In these cases, standard laser glasses for visible or near-infrared (400-1400 nm) lasers do not provide adequate protection.

4. How to choose the right glasses?

To ensure protection against far-infrared radiation:

① Check the wavelength range on the label (e.g., 10,000–11,000 nm)

② Confirm compliance with ANSI Z136, EN 207, or EN 208 standards

③ Choose products from reputable manufacturers that meet technical specifications, such as Thorlabs, LaserPair, NoIR, etc.

④ If the intensity of far-infrared radiation is high, consider wearing a full-face shield or other protective measures

Conclusion

While laser safety glasses are effective for protecting against many types of laser exposure, they do not automatically protect against far-infrared radiation unless they are specifically designed. If you work in an environment with sources of far-infrared radiation, it is critical to choose eyewear with the correct wavelength protection and optical density.