ATAGO DR-M2/1550(A) Multi-Wavelength Abbe Refractometer

Overview

The ATAGO DR-M2/1550(A) is a high-precision, multi-wavelength Abbe refractometer engineered for quantitative optical characterization of transparent and semi-transparent materials across the visible to near-infrared (NIR) spectrum. Unlike conventional single-wavelength refractometers, this instrument employs a tunable monochromatic light source combined with interchangeable interference filters to enable spectral dispersion analysis—supporting direct measurement of refractive index (n_D, n_F, n_C, n_e, n_v) and Abbe number (v_d, v_e) at user-selectable wavelengths from 450 nm to 1550 nm. Its optical design follows classical Abbe principle: critical angle detection via boundary line intersection in a double-prism configuration (main and auxiliary prisms), ensuring traceable, repeatable measurements compliant with ISO 21147:2022 and ASTM D1218 standards for refractive index determination. The integrated temperature-controlled sample stage (5–50 °C) mitigates thermal drift, while the high-resolution LCD display presents real-time digital readouts of both refractive index and Abbe number—eliminating parallax error associated with analog scale interpretation.

Key Features

• Multi-wavelength capability across four NIR/visible bands: 450–539 nm, 540–680 nm, 681–799 nm, and 800–1550 nm—enabling full dispersion curve generation
• High-resolution digital display: 0.0001 RI resolution and 0.1 Abbe number resolution, calibrated against NIST-traceable reference plates
• Interchangeable interference filter set (standard 589 nm; optional 486 nm, 656 nm, 546 nm, 480 nm, 644 nm, and custom-band filters) for wavelength-specific metrology
• Near-infrared observation eyepiece (RE-9119) and polarized viewing attachment (RE-1146) for enhanced contrast in low-reflectivity or birefringent samples
• Modular architecture: separate refractometer head (5.9 kg), power supply unit (3.0 kg), and monochromatic source module—facilitating maintenance and recalibration
• Compliant electrical design: dual-voltage input (AC 100–240 V, 50/60 Hz), CE-marked, and RoHS-conformant

Sample Compatibility & Compliance

The DR-M2/1550(A) accommodates liquid, paste, gel, and solid transparent media—including optical adhesives (e.g., LED encapsulants), lens coatings, polymer resins, specialty glasses, and semiconductor-grade immersion fluids. Its adjustable prism pressure mechanism ensures uniform contact without sample deformation, critical for soft-cure epoxies and silicone gels used in optoelectronic packaging. All measurements adhere to GLP documentation requirements when paired with optional DP-22(B) digital printer (model 3125), which logs timestamped RI/Abbe values with operator ID and calibration status. The system supports audit-ready data integrity per FDA 21 CFR Part 11 when integrated into validated laboratory informatics environments. Calibration verification follows ISO/IEC 17025 guidelines using certified reference materials (e.g., ATAGO RE-1195 calibration standard).

Software & Data Management

While the DR-M2/1550(A) operates as a standalone benchtop instrument, its RS-232C interface enables bidirectional communication with external PCs or LIMS platforms. Raw measurement data—including wavelength setting, temperature reading, RI value, Abbe number, and pass/fail flags—can be exported in ASCII format for post-processing in MATLAB, Python (NumPy/Pandas), or Excel. Optional DP-22(B) printer provides hard-copy output with embedded calibration certificate ID and environmental metadata. Firmware updates are delivered via USB memory stick, ensuring long-term compliance with evolving IEC 61000-4 electromagnetic compatibility standards.

Applications

• Quality control of LED die-attach adhesives and underfill materials—verifying refractive index match between encapsulant and chip substrate to minimize Fresnel losses
• R&D of gradient-index (GRIN) optical polymers and sol-gel-derived coatings for AR/HR filter stacks
• Characterization of telecom-grade optical fibers and planar lightwave circuits (PLCs) operating at 1310 nm and 1550 nm windows
• Validation of immersion oils for high-NA microscopy objectives (e.g., oil immersion at 546 nm or 633 nm)
• Material certification for ISO 10110-2 surface specification of optical components
• Academic research in photonic crystal fabrication, where precise n(λ) dispersion modeling informs bandgap tuning

FAQ

Does the DR-M2/1550(A) support automatic wavelength switching?

No—wavelength selection requires manual insertion of the corresponding interference filter; however, the modular filter holder allows rapid exchange with minimal alignment recalibration.

Can this refractometer measure turbid or opaque samples?

No—it is designed exclusively for optically transparent or translucent media; scattering or absorption above 10% at the selected wavelength will compromise boundary line detection.

Is temperature compensation applied automatically during measurement?

Yes—the built-in Peltier-controlled stage maintains setpoint temperature within ±0.1 °C, and the firmware applies real-time correction based on material-specific dn/dT coefficients stored in internal lookup tables.

What is the recommended recalibration interval?

ATAGO recommends annual verification using certified reference standards (e.g., RE-1195); more frequent checks are advised in regulated QC environments operating under ISO 9001 or IATF 16949.

Are replacement prisms available as service parts?

Yes—main and auxiliary prisms (part no. RE-16500) are field-replaceable and supplied with factory certification of surface flatness (λ/10) and refractive homogeneity.