Narrowband optical coatings optimized for specific laser wavelengths. Maximum reflectance or transmission at the laser line with high laser damage threshold for demanding industrial and scientific applications.
Laser line coatings are designed for a single specific wavelength — the laser emission line. Unlike broadband coatings, they concentrate all design freedom into optimizing performance at one wavelength, achieving the highest possible reflectance or transmission with maximum laser damage resistance.
High-reflection laser line mirrors use quarter-wave stacks tuned to the laser wavelength. A 1064nm HR mirror might use 25-35 layers of Ta2O5/SiO2, each precisely controlled to ±0.1nm thickness to achieve R > 99.9% at the design wavelength.
Laser line transmission filters (bandpass filters) pass only the laser wavelength while blocking pump light, plasma emission and ambient light. They typically use Fabry-Perot cavity designs with metal-dielectric or all-dielectric constructions.
The key advantage of laser line coatings over broadband alternatives is the higher achievable LIDT. By optimizing materials and layer thicknesses for a single wavelength, absorption is minimized and thermal management is improved.
| Parameter | Typical Values | Notes |
|---|---|---|
| Reflectance | > 99.9% at laser line | For HR mirrors |
| Transmission | > 99% at laser line | For AR/transmission optics |
| Bandwidth (HR) | ±2-5% of λ | Reflectance band |
| Bandwidth (filter) | 1-10nm FWHM | For bandpass filters |
| LIDT (ns) | Available: 20-100 J/cm² | 1064nm, 10ns, ISO 21254 |
| LIDT (ps/fs) | Available: 0.1-2 J/cm² | Short pulse designs |
| Absorption | < 10 ppm typical | IBS deposition |
| Common Lines | 193/248/308/355/532/1064/10600nm | All standard laser lines |
| Surface Quality | 20/10 scratch-dig | MIL-PRF-13830 |
| Laser Line | Material System | Substrate | Application |
|---|---|---|---|
| 193nm (ArF) | Al2O3/SiO2 or LaF3/AlF3 | CaF2, fused silica | Lithography, DUV |
| 248nm (KrF) | HfO2/SiO2 or Al2O3/SiO2 | CaF2, fused silica | Lithography, UV |
| 355nm (3rd Nd:YAG) | HfO2/SiO2 | Fused silica | UV marking, pump |
| 532nm (2nd Nd:YAG) | Ta2O5/SiO2 | BK7, fused silica | Green laser, pump |
| 1064nm (Nd:YAG) | Ta2O5/SiO2 | BK7, fused silica | Industrial, medical |
| 10.6μm (CO2) | ZnS/ThF4 or Ge/ZnS | ZnSe, Ge, Cu | Cutting, welding |
Cutting, welding and marking lasers use HR mirrors and AR-coated focusing optics. Key requirements: high CW/power density LIDT and long-term stability.
High-finesse cavities, optical clocks and precision spectroscopy use ultra-high reflectance mirrors (R > 99.99%) with minimal absorption and scattering.
Surgical and therapeutic laser systems require reliable mirrors and filters at wavelengths from UV (excimer) to mid-IR (Er:YAG, CO2).
Narrowband laser line filters reject background sunlight while passing the return signal. Typical specs: 1-3nm bandwidth, OD 6+ out-of-band blocking.
RGB laser projection systems combine red, green and blue laser lines using dichroic mirrors with laser-line-specific coatings.
PhotonEdge offers coated optical components compatible with Laser Line Filters & Mirrors. Explore related products below.
Laser line HR mirrors are optimized for maximum reflectance and LIDT at a single wavelength, while broadband HR mirrors trade peak performance for wider bandwidth. Laser line designs achieve higher LIDT.
CW damage is thermal — driven by absorption and thermal conductivity. Pulsed damage is mechanical — driven by peak electric field intensity. Different material systems and designs are optimized for each regime.
Standard laser line coatings are available for all common laser lines from 193nm (ArF excimer) to 10.6μm (CO2). Custom wavelengths can be designed for any laser source.
Define the laser wavelength, required bandwidth (FWHM), angular acceptance, out-of-band blocking (typically OD 4-6), and environmental requirements. Consider the solar background at your operating wavelength.
Our optical engineers can help you select or design the optimal coating for your application.
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