HunterLab D25NC Non-Contact Desktop Spectrophotometer
| Brand | HunterLab |
|---|---|
| Origin | USA |
| Model | D25NC |
| Product Type | Spectrophotometric Colorimeter |
| Instrument Type | Benchtop |
| Optical Geometry | d/8° integrating sphere |
| Light Source | Long-life LED |
| Spectral Range | 400–700 nm |
| Repeatability | ΔE*ab ≤ 0.03 |
Overview
The HunterLab D25NC is a non-contact, benchtop spectrophotometer engineered for high-reproducibility color measurement of heterogeneous, irregular, and textured surfaces—common in food, plastics, agricultural, and industrial manufacturing environments. Based on 60 years of spectral color science expertise, the D25NC implements a dual-axis optical architecture: a vertically aligned, motorized measurement head maintains precise standoff distance (automatically calibrated to ±0.1 mm), while a motor-driven rotating sample stage ensures full-surface averaging across up to 25 discrete positions per revolution. Its d/8° integrating sphere geometry conforms to CIE No. 15 and ASTM E308 standards, enabling accurate reflectance measurement under diffuse illumination and hemispherical collection. The system operates without physical contact—eliminating pressure-induced surface deformation, gloss distortion, or contamination risk—making it uniquely suited for soft, fragile, granular, or high-moisture samples such as extruded snacks, animal feed pellets, roasted coffee beans, or baked goods.
Key Features
- Non-contact measurement with auto-calibrated height control—ensures consistent geometry independent of sample thickness or topography
- Rotating 129 cm² sample platform (Ø128 mm) enabling full-area spectral averaging; 5 measurements/sec, 25 readings/cycle
- Long-life, thermally stabilized LED source covering 400–700 nm at 10 nm FWHM bandwidth; no warm-up required, <0.1% intensity drift over 8 hours
- Robust, tool-free modular design: optical head, stage, and base disassemble in <30 seconds for cleaning or calibration verification
- Onboard storage for 250 user-configurable methods and 2,000 sample records; USB host interface supports keyboard, barcode scanner, thermal printer, and host PC
- Low-power operation (<12 W typical), fanless thermal management, and IP20-rated enclosure suitable for production-floor deployment
Sample Compatibility & Compliance
The D25NC accommodates diverse physical forms—including loose powders, irregular solids (e.g., meat patties, almond pieces), layered composites (e.g., laminated packaging), and macro-textured surfaces (e.g., extruded plastic profiles, crushed stone)—without requiring cutting, pressing, or molding. Its non-contact mode eliminates operator-induced variability and meets GLP/GMP documentation requirements when paired with compliant software. Instrument performance aligns with ISO 11664-4 (CIE colorimetric observers), ASTM D2244 (color difference calculation), and ISO 9001 process validation frameworks. Traceable calibration is supported via NIST-traceable ceramic tiles and liquid standards; optional annual verification kits include spectral reflectance standards certified to ISO/IEC 17025-accredited labs.
Software & Data Management
The D25NC operates standalone via its intuitive color LCD interface or integrates seamlessly with HunterLab’s EasyMatch QC software (v5.0+). EasyMatch QC provides full audit trail functionality compliant with FDA 21 CFR Part 11—including electronic signatures, user-level permissions, and immutable data logging. It supports SPC charting (X-bar/R, Cp/Cpk), tolerance mapping against L*a*b*, ΔE*00, or custom color spaces, and automated report generation (PDF, CSV, XML). Raw spectral data (31-point reflectance per nm interval) is exportable for third-party analysis or ML-based color consistency modeling. All firmware updates and method libraries are delivered via secure HTTPS through HunterLab’s Customer Portal.
Applications
- Food & Beverage: Real-time monitoring of color uniformity in fried potato products (chips, fries), baked items (bread, cookies, buns), roasted beans (coffee, cocoa), ground spices, and animal feed pellets
- Plastics & Polymers: In-line validation of extruded profiles, injection-molded parts, and recycled resin batches where surface texture or curvature prevents contact probe use
- Agriculture & Feed: Objective assessment of grain maturity, seed coat variation, and pellet integrity in compound feed formulations
- Building Materials: Quantification of pigment dispersion in decorative aggregates, stucco, and architectural coatings
- Pharmaceutical Excipients: Non-destructive evaluation of powder blend homogeneity and tablet coating consistency
FAQ
Does the D25NC require sample preparation such as grinding or pressing?
No—its non-contact design enables direct measurement of intact, unaltered samples including whole coffee beans, cereal grains, and extruded snack pieces.
How is measurement height controlled and verified?
An integrated capacitive sensor continuously monitors standoff distance; height is auto-compensated in real time and logged with each spectrum for traceability.
Can the D25NC be validated for regulated environments (e.g., FDA-regulated facilities)?
Yes—when used with EasyMatch QC in 21 CFR Part 11 mode and documented calibration procedures, it satisfies GxP audit requirements for color-critical processes.
What spectral resolution does the instrument provide?
It captures reflectance at 10-nm intervals across 400–700 nm, yielding 31 discrete wavelength points per measurement, fully compatible with CIE 1931 2° standard observer functions.
Is routine maintenance required beyond cleaning?
Only periodic verification using supplied calibration tiles is recommended; no lamp replacement or optical alignment is needed during the instrument’s rated service life (>100,000 measurements).
