FAQs

Yes. Windows are easily machined and are provided with a pressure sensitive paper film to guard the plastic during processing. We recommend a fine-tooth plastics blade on a table saw. Sheet can be sawn, drilled, and machined like wood or soft metals when using tools, drills and blades designed for plastic materials/laminates.

The thickness tolerance on 24″x36″ sheet is .010″.

The thickness tolerance on 36″x48″ sheet or larger is .015″.

Standard sizes are shown on each product’s page. Common sizes include 24″x36″ and 36″x48″. Common thicknesses include 0.125″ (3mm), 0.145″ (3.5mm), 0.236″ (6mm), and 0.250″ (6.3mm).

Absolutely. Custom sizes are common place, custom specifications/certifications of existing products are often requested, and custom filters using different dyes and additives can also be done depending on the degree of difficulty.

A rough cut size sheet is created when a sheet is roughly cut to its final size. The sheet will typically measure closer to 24.5″x3 6.5″ (on a sheet sold as 24″x36″). On a 24″x36″ sheet, you are always guaranteed 24″x36″ of useable material. Many customers find that this slightly larger size allows for better utilization when cutting. For example, should one require (4) four pieces exactly 12”x 18” this is possible with a rough cut sheet size since the saw blade width does not limit you to (4) 11 7/8ths”x17 7/8th”. In other words, the saw blade cutting tolerance (kerf) is mitigated. Please note that these sheets may come with slightly uneven edges, small chips on the corners, or minute voids on edges.

A neat cut sheet size is when a sheet is cut to precisely the size it is listed, precisely 24” x 36” for example. Note that on custom size orders all sheet are neat cut to your precise dimensions with a tolerance of 1/32”.

We currently manufacture up to 4’ x 6’ sheet

We strive to ship our standard products within 24 hours from time of receipt of order. For a large quantity of standard sizes or custom sizes, typically we have a 4-6 weeks lead time. As for new filter designs using our known library of dyes and additives, a 6-8 week lead time is typical.

We typically require a minimum run size of seven (7) sheet per batch

Transmission with respect to laser protection is a measure of how much energy is passing through a sheet at a specific wavelength. Optical Density is simply a logarithmic scale of that transmission.

OD = -logT(at a given wavelength)

Examples:

OD =0 T=100%

OD=1  T=10%

OD=2  T=1%

OD=3  T=0.1%

OD=4  T=0.01%

OD=5  T=0.001%

So, it is important to observe that an increase in OD by one unit increases protection 10X. When specifying OD, do not assume higher OD means “better”. Higher OD means more dyes and darker sheet which increases cost and decreases user’s vision. It is important to specify the OD you require for your application.

When one wants to know what a product looks like we often think of color – it’s green or it’s blue, for example. Visible light transmission, defined differently by dozens of standards, is a measure of how much visible light is coming through, aka transmitting, through that color. A lower percentage such as 10%T (typical of sunglasses) is darker than a moderate percentage

Huge question. The answer is NOT “I need X OD at Y wavelength because this is what it says on my glasses.”

Every facility/company should have a designated Laser Safety Officer (LSO) who ideally calculates the nominal hazard zone (NHZ) for their Class 3b and 4 lasers based on the industry user standards. ANSI Z136.1 “For the Safe Use of Lasers” is the best standard for one to become familiar with initially. If you define your NHZ as your machine, then any optical density requirements of windows/view ports are based generally, on the type of laser, laser hazard wavelength(s) and beam divergence to that window. If one defines a room as the NHZ, then the optical densities required are based on the distance to the closest room window.

At PSI we manufacture our acrylic sheet using cell casting. This means we start with a liquid monomer, add our dyestuffs and other additives, pour between molds assembled from optical quality glass sheet and oven cure over up to two days. The result is outstanding optical quality, and a significantly cross-linked material that has very good abrasion resistance and chemical resistance. Cast acrylic can be bent upon heating, but is a thermoset, meaning it will not melt back to a liquid state. Extruded acrylic is made from a thermoplastic resin which is melted, extruded through rollers and cooled. It requires 500 to 1000 lbs per run, is soft, and will melt readily.

Optically cast acrylic has excellent clarity and lower Abbe number (consistent refractive index throughout the visible region when it is manufactured as described above. Polycabonate sheet is a thermoplastic material and is extruded as described above.  It is very, soft and so PSI only provides polycarbonate sheet with a protective, hard coating.

Cell cast acrylic and polished optical glass are the two best optical filter materials. Acrylic is a polymer which allow for easy fabrication, small to large sizes, great laser protection, formulation at any thickness from 1mm to 6+mm, and reasonable laser damage thresholds combined with a low cost per square foot. Glass has excellent transmission, optical properties and laser damage thresholds. It is difficult to re-engineer in different thicknesses or create new filter designs. It is multiple times more expensive than acrylic per unit area, and available in small sizes, making it most useful in small view ports, or eyewear.

Film for laser protection is no longer in mainstream use. It was made from soft vinyl materials combined with additives which are no longer regulatory compliant. The very thin film carried reasonable optical density but, had unacceptably low burn trough times. If one has a drawing or specification calling for the use of film, or has this product in a protective system, please contact us for the suitable replacement sheet material.

Yes. Our sheet products allow the user to comply with the requirements of ANSI Z136.1 and its relevant sub documents. We will provide a certification of compliance to our standard specifications (or your custom specifications) along with full lot traceability allowing you to label and certify to the standard.

Yes. Typically one requires compliance to one of the following standards; EN 122154 – Screens for Laser Working Places (usually for facility windows in rooms or doors), EN 60825 – Safety of Laser Products (usually for OEM equipment windows or viewing ports), or EN 207 – Personal eye-protection equipment – Filters and eye-protectors against laser radiation (for application when using sheet material or lens blanks to be fashioned into personal protection). Once we know which standard requirements you have, we will provide a certification of compliance to your specifications along with full lot traceability. You can use this information to work with your certified third-party notified body to receive your compliance certificate.

Once you have your laser hazard wavelength(s) and Optical Density (OD) requirements at each wavelength defined, you can refer to our Application Guides and Product Matrix reference material to help you narrow down your choice. In addition, if you have a part number from a functionally equivalent mating competitive product, our Cross Reference guide can help. If you find that you still require assistance, please contact us via email at sales@laserprotection.com and we will get back to you promptly.