ATAGO PR-RI Digital Refractometer for Refractive Index Measurement
| Brand | ATAGO |
|---|---|
| Origin | Japan |
| Model | PR-RI |
| Product Type | Handheld Refractometer |
| Display | Digital LCD |
| Temperature Control | None |
| Measurement Range | 1.3306–1.4436 RIU |
| Accuracy | ±0.0002 RIU |
| Compliance | ISO 17025-compatible operation, ASTM D1218, JIS K 0061 |
Overview
The ATAGO PR-RI Digital Refractometer is a precision handheld optical instrument engineered for rapid, non-destructive measurement of refractive index (RI) across liquid and semi-liquid samples. Based on the principle of total internal reflection at the prism-sample interface, the PR-RI employs a high-stability sapphire prism and an integrated LED light source to deliver repeatable RI readings in real time. Unlike traditional Abbe-type refractometers requiring manual scale interpretation, the PR-RI utilizes a high-resolution CCD sensor array and embedded optical calibration algorithms to convert critical angle displacement directly into digital RI values with traceable metrological integrity. Designed for field-deployable and benchtop use in quality control laboratories, R&D facilities, and production environments, the device operates without external power adapters—powered solely by two AAA batteries—enabling continuous operation for over 10,000 measurements per set. Its compact form factor (145 × 55 × 35 mm), IP65-rated housing, and ergonomic grip ensure reliable performance under variable ambient conditions including humidity fluctuations and moderate temperature gradients.
Key Features
- High-precision digital readout with 0.0001 resolution and ±0.0002 RIU accuracy, certified against NIST-traceable glycerol standards
- Sapphire prism surface (Mohs hardness 9) resistant to scratching, chemical corrosion, and thermal drift
- Auto-zero function with built-in reference mode for rapid recalibration using distilled water (nD20 = 1.3330)
- Real-time temperature compensation algorithm (based on internal thermistor, range: 10–40 °C), though no active temperature control is integrated
- Large backlit LCD display (128 × 64 pixels) with dual-unit capability: refractive index (RIU) and optional Brix-equivalent output (when calibrated with sucrose solutions)
- USB-C data export interface supporting CSV log files with timestamp, sample ID, operator code, and environmental temperature metadata
- Compliant with ISO/IEC 17025 documentation requirements for instrument verification records and calibration history tracking
Sample Compatibility & Compliance
The PR-RI accommodates aqueous solutions, organic solvents (e.g., ethanol, acetone, ethylene glycol), oils, polymer precursors, and low-viscosity resins—provided samples are optically homogeneous and free of suspended particulates or air bubbles. Minimum sample volume required is 0.3 mL, applied directly onto the prism surface via pipette or dropper. The instrument meets mechanical and optical safety requirements per IEC 61010-1:2010 for laboratory electrical equipment. While not intrinsically rated for hazardous locations, its battery-powered architecture eliminates grounding risks in solvent-handling areas. For regulated industries, the PR-RI supports GLP-compliant workflows through user-accessible audit trails, password-protected configuration settings, and firmware version logging—aligning with FDA 21 CFR Part 11 principles when used with validated data management software.
Software & Data Management
ATAGO’s optional PC-based “RefractoLink” software (v3.2+) enables centralized instrument configuration, firmware updates, and batch report generation. Raw measurement logs include ISO 8601 timestamps, operator-assigned sample identifiers, ambient temperature, and pass/fail flags based on user-defined specification limits. Export formats include .csv for LIMS integration and .pdf for QA sign-off. All data files contain embedded digital signatures verifying origin and immutability post-export. Instrument memory retains up to 1,000 measurements locally; automatic overwrite logic prevents data loss during extended unattended operation.
Applications
- Pharmaceutical excipient QC: verification of glycerin, propylene glycol, and PEG purity per USP
- Chemical manufacturing: concentration monitoring of sodium hydroxide, sulfuric acid, and hydrogen peroxide solutions
- Food & beverage: validation of syrup density, fruit juice dilution, and alcohol content estimation (with empirical correlation tables)
- Electronics: inspection of photoresist solvent blends and cleaning agent composition stability
- Academic research: optical property characterization of nanofluids, ionic liquids, and bio-based lubricants
FAQ
Does the PR-RI require periodic factory recalibration?
Yes—ATAGO recommends annual recalibration against certified reference materials at an ISO/IEC 17025-accredited service center to maintain stated accuracy specifications.
Can the PR-RI measure turbid or colloidal samples?
No—scattering media interfere with critical angle detection; centrifugation or filtration is required prior to analysis.
Is temperature correction applied automatically during measurement?
Yes—the internal thermistor continuously monitors prism temperature and applies a polynomial compensation model derived from ATAGO’s proprietary RI vs. T database for common solvents.
What is the warranty coverage for the PR-RI?
ATAGO provides a 2-year limited warranty covering defects in materials and workmanship, excluding prism surface damage caused by improper cleaning or abrasive contact.
Is the USB-C port compatible with macOS and Linux systems?
Yes—RefractoLink software is available for Windows 10/11, macOS 12+, and Ubuntu LTS 22.04+; driver-free HID-class communication ensures plug-and-play functionality.
