Dielectric Coated Mirrors: High-Performance Optical Solutions by Bena Optics

Dielectric Coated Mirrors: High-Performance Optical Solutions

Dielectric coated mirrors are crafted by depositing multiple layers of dielectric coatings on optical components, enhancing reflectivity through interference superposition within a specific wavelength range. These mirrors offer high reflectance, are suitable for broad wavelength spectra, and do not absorb light, making them durable and suitable for multi-wavelength laser systems. However, they are characterized by thicker layers, angle sensitivity, and higher costs.

Key Features of Dielectric Coated Mirrors

• High Reflectance: Reflectance is enhanced through interference superposition.

• Wide Wavelength Range: Suitable for broad spectral applications.

• Durability: Hard coating resistant to damage.

• Sensitivity: Highly angle-sensitive and relatively costly.

Applications and Categories

For applications requiring ultra-high reflectance (greater than 99%) or minimal light absorption, dielectric coatings are indispensable. These mirrors are almost non-absorptive and can withstand continuous laser irradiation. Common types include:

• Broadband Multilayer Dielectric Coated Mirrors: Offering high reflectance and broad spectral usability, these mirrors are ideal for precise optical systems (weak light or low-loss systems), laser optical systems up to 1 W, and multi-wavelength laser systems.

• Laser Multilayer Dielectric Coated Mirrors: Featuring high reflectance, minimal loss, and high laser damage thresholds, these mirrors are suitable for laser optical systems and high-power laser systems. They are typically used at a 45° angle of incidence and are less versatile in wavelength range.

For specialized applications, dielectric coated mirrors can be manufactured as ultrafast mirrors and harmonic separators. These mirrors are more durable, easier to clean, and have higher damage thresholds, commonly used in the visible and mid-infrared spectral regions.

Dielectric coated mirrors are sensitive to the angle of incidence. Unless specified, the default angle of incidence for dielectric coated mirrors is 45°. Deviations from this angle can significantly affect reflectance. For example, a mirror specified for a 45° angle typically has a usable range of 45±3°. Beyond this range, reflectance can vary greatly. Some dielectric coatings are designed for angles ranging from 0° to 45°, where the reflectance curve shifts with the angle of incidence, requiring careful application.

Bena Optics offers dielectric coated mirrors on UV fused silica substrates, with an average reflectance greater than 99% across the 400-1650 nm wavelength range (45° angle of incidence). Available in various shapes including circular, elliptical, square, and D-shaped mirrors, these products cater to diverse application needs.

Bena Optics also provides broadband dielectric coated right-angle prism mirrors, capable of deflecting or precisely aligning beams in the 400-1100 nm visible to near-infrared range, with reflectance exceeding 99%.

For specialized applications, Bena Optics offers:

• Nd:YAG Mirrors: Designed for 1064 nm fundamental, 532 nm second harmonic, 355 nm third harmonic, and 266 nm fourth harmonic lasers, with high reflectance for both s and p polarization.

• Ultrafast Mirrors: Featuring low group delay dispersion (GDD) for applications using various lasers.

• Harmonic Separators: Specifically designed to separate the harmonics of Nd:YAG lasers at a 45° angle of incidence.

Dielectric coated mirrors offer unparalleled reflectance and spectral versatility, making them essential for high-precision optical systems. With Bena Optics, you can access a wide range of high-quality dielectric coated mirrors tailored to meet your specific needs. Whether you require broadband mirrors, laser mirrors, ultrafast mirrors, or harmonic separators, Bena Optics has the perfect solution for you.

Visit our website to explore our full range of optical products and discover how we can help you achieve optimal performance in your optical systems.