MiXran Meg1115 Reflective Neutral Density Filter (Visible–Near-Infrared)
| Brand | MiXran |
|---|---|
| Origin | Beijing, China |
| Model | Meg1115 |
| Component Category | Optical Element |
| Design Wavelength | 550 nm |
| Optical Density (OD) | 0.1–3.0 (11 standard grades) |
| Transmission (T) | 79%–0.10% |
| Available Apertures | Φ12.5 mm, Φ25 mm, 50×50 mm |
Overview
The MiXran Meg1115 is a precision-engineered reflective neutral density (ND) filter designed for stable, wavelength-specific attenuation across the visible to near-infrared spectrum (400–1100 nm), with nominal calibration at 550 nm. Unlike absorptive ND filters—which risk thermal distortion and non-uniform transmission under high-intensity illumination—the Meg1115 employs a dielectric multilayer coating deposited on optical-grade fused silica or BK7 substrates. This reflective architecture ensures minimal absorption, negligible heating, and exceptional power-handling capability—critical for laser alignment, optical density calibration, spectrometer dynamic range extension, and photodetector protection in both research and industrial metrology environments. Each filter is individually characterized and certified for optical density (OD) tolerance of ±0.05 OD at 550 nm, traceable to NIST-traceable reference standards.
Key Features
- Reflective dielectric coating technology for low thermal load and high damage threshold (≥5 J/cm² for 10 ns pulses at 532 nm, typical)
- 11 standardized OD values spanning 0.1 to 3.0 (corresponding to 79% to 0.10% transmission at 550 nm)
- High spectral uniformity: <±1.5% transmission variation across clear aperture (measured at 550 nm)
- Substrate options: Fused silica (for UV-VIS-NIR broadband stability) or BK7 (cost-optimized VIS-NIR performance)
- Surface quality: 60–40 scratch-dig per MIL-PRF-13830B; surface flatness λ/4 @ 633 nm
- AR-coated backside (optional) to suppress ghost reflections and interference fringes in multi-filter stacks
Sample Compatibility & Compliance
The Meg1115 series is compatible with standard optical mounts (e.g., SM1-threaded lens tubes, kinematic mirror mounts, and filter wheels with 12.5 mm, 25 mm, or 50×50 mm slots). All filters meet ISO 9022-3:2015 (Environmental testing — Optics and photonics — Mechanical, thermal and humidity tests) for operational stability under 5–40 °C ambient temperature and ≤80% RH. Certificates of Conformance include measured OD spectra (350–1100 nm, 1 nm resolution), transmission uniformity maps, and substrate material certification. For regulated applications—including ISO/IEC 17025-accredited calibration labs—the filters support documented traceability to national metrology institutes via optional calibration reports compliant with ISO/IEC 17025:2017 Annex A.2.
Software & Data Management
While the Meg1115 is a passive optical component, its integration into automated optical systems benefits from standardized digital asset management. Each product variant (e.g., GMNF-VIS-D25-005) carries a unique 12-digit alphanumeric serial number etched onto the substrate edge. This identifier links to downloadable technical files—including full spectral transmission curves (.CSV), dimensional drawings (.PDF), and calibration certificates (.PDF)—via MiXran’s secure OEM portal. For customers operating under FDA 21 CFR Part 11 or EU Annex 11 requirements, audit-trail-enabled access logs and electronic signature-capable certificate issuance are available upon request. No proprietary software installation is required; all data files adhere to open, machine-readable formats suitable for LIMS or ELN ingestion.
Applications
- Laser power attenuation in interferometry, holography, and cavity ring-down spectroscopy
- Dynamic range control in CCD/CMOS-based spectrometers and hyperspectral imaging systems
- Reference-grade optical density verification for radiometric and photometric calibration laboratories
- Beam balancing in multi-channel optical detection setups (e.g., fluorescence lifetime imaging, OCT light engines)
- Attenuation staging in optical safety testing per IEC 60825-1:2014 (Laser product safety)
- Calibration of photodiode linearity and responsivity across 400–1000 nm
FAQ
What is the difference between reflective and absorptive neutral density filters?
Reflective ND filters like the Meg1115 use interference-based dielectric coatings to reflect excess light, minimizing heat buildup and preserving beam wavefront integrity. Absorptive filters rely on doped glass or polymer films that convert light to heat—risking thermal lensing and damage at high irradiance.
Can the Meg1115 be used outside its specified 550 nm design wavelength?
Yes—its transmission curve remains monotonic and predictable across 400–1100 nm, though OD values deviate slightly from nominal (±0.1 OD typical at extremes); spectral data for each unit is provided in its certificate.
Is custom OD or size available?
Yes—MiXran offers OEM customization including non-standard OD values (0.05–4.0 in 0.05 increments), substrate materials (CaF₂, sapphire), and dimensions up to 100×100 mm with matched surface flatness and coating specifications.
Do these filters require cleaning, and what is the recommended procedure?
Yes—use only spectroscopic-grade acetone or isopropanol with Class 100 cleanroom-grade lens tissue; avoid ultrasonic cleaning unless substrate and coating are explicitly rated for it (fused silica variants only).
How is optical density verified during manufacturing?
Each filter undergoes double-beam spectrophotometric measurement using a calibrated PerkinElmer Lambda 1050+ with 1 nm bandwidth, referenced against NIST-traceable SRM 2065a and SRM 2036, per ASTM E275-22 Annex A1.
