2 inch broadband dielectric mirror fused silica

Product Description

Precision 2″ (50.8mm) Diameter, 0.5″ (12.7mm) Thick Optical Mirror – Broadband Dielectric Coating

This precision 2″ (50.8mm) diameter, 0.5″ (12.7mm) thick optical mirror is crafted from a fused silica substrate, prized for its low thermal expansion, high optical clarity, and durability in varying environmental conditions. It features a multi-layer broadband dielectric coating that delivers exceptional reflectivity (>98-99%) across a wide visible to near-infrared wavelength range (approximately 400-1100nm), outperforming standard metallic coatings with lower absorption and higher laser damage resistance.

Fused silica is an ideal substrate for precision mirrors, offering excellent thermal stability, resistance to thermal shock, and high purity that minimizes absorption and scatter . Dielectric coatings provide superior performance compared to metallic coatings, with higher reflectivity and greater durability in high-power laser applications .

---

Key Specifications

---

Condition Note – Minor Scratch

The mirror is in great surplus condition overall, with only a minor fragmented straight line scratch in one place near the center. This cosmetic defect may have negligible impact for non-critical applications.

Practical Impact of Minor Scratches:

• Visual use (telescopes, imaging): Minor scratches often have negligible impact on visual performance. As noted in astronomy forums, “unless the issue described is a significant damage, the answers are constantly the same: ‘…you won’t notice a difference for visual use…'”

• Laser applications: May cause minimal scatter depending on beam size and location. For applications where the beam can be positioned away from the scratch, impact is minimal.

• Non-critical setups: Ideal for educational, prototyping, or alignment applications where absolute perfection is not required.

This scratch represents an opportunity to acquire a high-quality precision optic at a significant discount compared to new equivalents.

---

Material Advantages – Fused Silica

Fused silica offers exceptional properties for precision optical mirrors :

---

Dielectric Coating Advantages

Dielectric coatings offer significant advantages over metallic coatings :

• >98-99% Reflectivity: Significantly higher than metallic coatings (typically 90-96%)

• Lower Absorption: Reduced heating in high-power applications

• Higher Laser Damage Threshold: Suitable for demanding laser systems

• Durability: Hard, environmentally stable coatings resistant to cleaning

• Broadband Performance: High reflectivity across entire 400-1100nm range

Daheng Optics’ broadband laser mirrors with similar specifications (fused silica substrate, 400-700nm, 50.8mm diameter, 9mm thickness) offer >99% reflectivity and laser damage thresholds >5J/cm² . This mirror’s 12.7mm thickness provides enhanced rigidity and thermal management.

---

Applications

Laser Beam Steering:

• Ideal for directing laser beams in research, industrial, or educational setups

• High reflectivity minimizes power loss in beam delivery systems

• Broadband coating accommodates multiple laser wavelengths

Optical Alignment:

• Precision reference for aligning optical systems

• Visible coating aids in visual alignment with HeNe or diode lasers

Scientific Instruments:

• Spectrometers and interferometers

• Imaging systems and telescopes

• Machine vision and inspection systems

Research and Education:

• University and laboratory optics experiments

• Photonics and laser demonstrations

• Prototyping and system development

Custom Optics Projects:

• Beam expanders and telescopes

• Optical path folding

• Multi-wavelength experiments

---

Comparative Value – New vs. Surplus

---

Condition Summary

⚠ NOTE: The minor scratch is described accurately to ensure full transparency. For many applications, this will have no practical impact on performance .