How To Choose Laser Safety Glass

Discover Essential Tips for Selecting the Right Laser Safety Glasses

In environments where lasers are in use, safety is a top priority—especially when it comes to protecting your eyes from potentially harmful radiation. Whether you’re working in a medical facility, laboratory, or industrial setting, choosing the right laser safety glass is crucial.
But with so many options available, how do you know which one offers the best protection without compromising on comfort or visibility?
In this guide, we’ll walk you through the essential factors to consider when selecting Laser Safety Sheets, from optical density to visible light transmittance, ensuring you make an informed decision for your unique needs.

Key Factors to Consider When Choosing Laser Safety Glass

Laser Wavelength

Laser Wavelength is the spatial period of the wave, representing the distance over which the wave’s shape repeats.

Ultraviolet (UV): 100 nm to 400 nm.
Visible: 400 nm to 700 nm (e.g., red light at ~650 nm, green at ~532 nm, blue at ~450 nm).
Infrared (IR): 700 nm to 1 mm (e.g., near-infrared at ~800 nm, mid-infrared at ~10.6 µm).

Different wavelengths interact differently with materials.
Infrared lasers with wavelengths of 808nm, 980nm, and 1064nm are invisible to the naked eye and are widely used in industries such as scientific research, military defense, and communication lighting.

Shorter wavelengths, closer to the ultraviolet spectrum, offer higher energy and are applied in various fields, driving advancements in technology and daily life.

Laser safety glasses are designed to block or attenuate specific wavelengths of laser light. Different lasers emit light at different wavelengths (e.g., 532 nm for green lasers, 1064 nm for Nd:YAG lasers, or 10.6 µm for CO2 lasers).

Matching laser safety glasses to the specific wavelength of the laser is essential for effective eye protection, compliance with safety standards, and preventing serious injuries.

Picture from Wikipedia File:Commercial laser lines.svg

Optical Density (OD)

Optical Density (OD) is a measure of how effectively a material (such as laser safety glasses, filters, or other optical components) attenuates or blocks light of a specific wavelength. It is a logarithmic scale that quantifies the reduction in light intensity as it passes through the material.

OD refers to how much light a material can absorb. In laser safety glasses, a higher OD value means the material blocks more of the laser’s intensity.

OD indicates the attenuation factor of the laser light. For example, an OD of 3 would mean the material reduces the intensity by 1,000 times.
Different lasers (visible, infrared, etc.) require different OD levels for safe protection, with higher-powered lasers requiring a higher OD.

Depending on the laser class, you may need glasses with varying OD values. For example, high-powered Class 4 lasers need glasses with higher OD (5 or higher).

Contact with Excelite guys to recommend the laser protective glass.

Visible Light Transmittance (VLT)

Visible Light Transmittance (VLT) refers to the percentage of visible light that passes through a material, such as laser safety glass or polycarbonate sheets. It’s a crucial factor when selecting protective eyewear or materials for laser safety, as it affects how much light you can see through the protective barrier.

High VLT: 50% to 80% — Often used for lower-powered lasers where visibility is important (e.g., in research labs).
Moderate VLT: 30% to 50% — Suitable for mid-range lasers where a balance of visibility and protection is needed.
Low VLT: 10% to 30% — Used for high-powered lasers (e.g., Class 4 lasers), offering maximum protection but reducing visibility.

If you’re working with lasers, ensuring your eyes are protected is absolutely essential. Whether you’re dealing with aiming beams, diffused viewing, or direct laser exposure, the right laser safety glasses can make all the difference. Let me walk you through the common materials used in laser safety glasses and why they’re so important for your safety.

Polycarbonate
Polycarbonate laser protective sheet is a lightweight, impact-resistant material that offers excellent optical clarity. It’s often used for low- to medium-power lasers and is particularly effective for visible and near-infrared (NIR) wavelengths. However, it’s important to note that polycarbonate may not provide sufficient protection for high-power lasers or certain far-infrared wavelengths. Always verify the Optical Density (OD) to ensure it meets your specific needs.

Acrylic (PMMA)
Acrylic, also known as PMMA, is a lightweight and cost-effective material that can be dyed to block specific wavelengths. It’s suitable for low-power lasers and visible wavelengths and is often used in educational or hobbyist settings. However, acrylic is less durable than polycarbonate or glass and is not recommended for high-power lasers.