Choosing the right protective window for lasers
What do you need to bear in mind when choosing the right protective window for lasers? It’s an important question. What material is it made of, and how does it actually work?
Material och funktion
Our laser safety windows are manufactured from PMMA (polymethyl methacrylate, also known as acrylic glass) and PC (polycarbonate). A safety window acts as a filter. The filter can operate in two ways: through a thin surface coating, or through absorption. Our filters use the latter method, meaning they absorb light within a specific wavelength.
Vad är laser och ljus?
To understand what light is, we need a little technical background. Light is a form of radiation, and the light-sensitive receptors in the eye detect light radiation within the range of 380 nanometres (nm) to approximately 800 nanometres. What we perceive as colours is, in fact, radiation of different frequencies. Violet or blue light has a short wavelength, whilst red has a long wavelength. Radiation with a shorter wavelength than the eye can perceive is called ultraviolet light, or UV. At the other end of the spectrum, with wavelengths too long to be detected by the eye’s receptors, we have infrared light, or IR.
Teknisk data för fönster
For safety windows, there is also what is known as an OD curve, which shows the level of protection and light transmission. OD stands for Optical Density and is a measure of how effective a filter is at a specific wavelength. OD2 provides a low level of protection, whilst OD10 provides a very high level of protection. If you contact us regarding safety windows, we will ask you two questions: What wavelength does the laser operate at? What protection class is required?
Important to bear in mind
Getting a material to absorb light at a specific wavelength, and having it tested and approved in accordance with comprehensive requirements, is a challenge. It is not simply ‘a small piece of plastic’ that will do the job. The material must meet stringent international standards. You should therefore be vigilant when looking for this type of product. Be critical of your sources; request documentation on how the material has been tested and by which certifying body. Working with lasers can cause serious and permanent injury!
We have moved our protective windows directly into the ‘Materials’ category, under ‘Laser Windows’. Please have a look there to see if we have the protective window you need.
Välja rätt skyddsfönster för laser