UV-Vis-NIR Spectrophotometer with Integrating Sphere

What is the UV-Vis-NIR Spectrophotometer with Integrating Sphere?

A UV-Vis-NIR spectrophotometer with integrating sphere measures transmittance and diffuse or specular reflectance from 190 to 2500 nm or beyond. It is the standard research tool for glass, coatings, photovoltaic materials, powders and other solids that cannot be measured in a cuvette.

Overview

This instrument is a double-beam scanning spectrophotometer with a double-grating monochromator, photomultiplier tube for UV-Vis and PbS or InGaAs detector for the near-infrared. A 60 mm or 150 mm integrating sphere coated with PTFE or barium sulfate collects all scattered light from solids, films and powders. Accessories include 8° specular reflectance, variable-angle absolute reflectance and transmission holders for large panels. Wavelength range typically runs from 190 to 2500 nm, extended to 3300 nm with an additional detector. Bandwidth is selectable from 0.05 to 5 nm in UV-Vis, and photometric range exceeds 6 A with stray light below 0.00008% T. Diffuse reflectance data convert to Kubelka–Munk function for band-gap estimation of semiconductors, and solar-weighted transmittance for architectural glass. Sample alignment and sphere calibration with certified reflectance standards are essential to reliable results.

How does it work?

UV-Vis instruments pass light of selected wavelength through or onto a sample and measure the ratio of transmitted or reflected intensity to a reference. Sources are typically a deuterium lamp for ultraviolet and a tungsten-halogen lamp for visible and near-infrared, often replaced by xenon flash lamps or LEDs in compact designs. Wavelength selection uses a scanning monochromator with a holographic grating, or a fixed grating that disperses light onto a diode-array or CCD detector so the whole spectrum is captured at once. Photomultiplier tubes, silicon photodiodes or InGaAs detectors convert the light to an electrical signal. Absorbance is calculated as −log10 of transmittance and relates to concentration by the Beer–Lambert law. Stray light, bandwidth and photometric linearity define performance at high absorbance, while integrating spheres and fiber probes adapt the same principle to solids, films and in-situ measurements.

What are the key features?

• Double-grating monochromator delivers very low stray light for high-absorbance samples.
• Integrating sphere collects total and diffuse reflectance and transmittance from solids.
• Extended range to 2500 nm or 3300 nm with PbS or InGaAs detectors.
• Variable bandwidth from 0.05 to 5 nm balances resolution and signal.
• Specular reflectance and variable-angle accessories expand sampling options.
• Software calculates Kubelka–Munk, solar transmittance and color coordinates.

What are the technical specifications?

A typical uv-vis-nir spectrophotometer with integrating sphere configuration offers wavelength range of 190–2500 nm, spectral bandwidth (UV-Vis) of 0.05–5 nm variable, wavelength accuracy of ±0.1 nm (UV-Vis), ±0.4 nm (NIR), photometric range of −6 to 6 A, stray light of ≤0.00008% T at 220 nm (NaI) and detectors of PMT (UV-Vis), PbS or InGaAs (NIR). Values are indicative of the product class; the exact figures for each configuration are confirmed on the quotation and the calibration documents supplied with the instrument.

Which applications is it used for?

The UV-Vis-NIR Spectrophotometer with Integrating Sphere is used in architectural and automotive glass, photovoltaic cell and coating research, semiconductor band-gap determination, powder and pigment diffuse reflectance and optical filter and lens characterization. Across the wider UV-Vis class, laboratories also deploy it for reaction kinetics and enzyme assays, nanoparticle plasmon resonance characterization and thin-film and coating optical properties.

Which standards and certifications apply?

Relevant standards and methods include ASTM E275, ASTM E925, ASTM E958, USP <857>, Ph. Eur. 2.2.25, ISO 8655-7 and GB/T 26798. Certification candidates for this model are CE, ISO 9001 manufacturing and IEC 61010-1 safety; each is to be confirmed for the specific configuration before shipment, and certificates are supplied only where they have been issued.

Allow lamps to warm up for 15–30 minutes and perform a baseline correction before every measurement session. Verify performance periodically using holmium oxide or didymium filters for wavelength accuracy, potassium dichromate solutions for photometric accuracy and sodium iodide or potassium chloride solutions for stray light. Use matched quartz cuvettes for the UV and keep optical surfaces clean and free of fingerprints. Replace the deuterium lamp after its rated life of around 2000 hours. Control ambient temperature and vibration, and keep dust and solvent vapors away from the optics. For regulated laboratories, schedule IQ/OQ/PQ and use software with audit trails and access control.

How do I select the right UV-Vis-NIR Spectrophotometer with Integrating Sphere?

Select this configuration when the sample is solid, scattering or requires near-infrared coverage. It is more costly and larger than a standard UV-Vis system. In an RFQ, specify wavelength range, sphere diameter, required accessories, reflectance standards, sample size limits and any spectral-weighting calculations needed.

How does it compare with other UV-Vis variants?

Choose a UV-Vis spectroscopy instrument according to spectral speed, wavelength range, sample type and accessory needs. Diode-array and CCD instruments capture a full spectrum in under a second and suit kinetics or unstable samples, but stray light is higher than in scanning double-beam systems that remain the choice for high-absorbance work. Extending to 3300 nm with a PbS or InGaAs detector requires a UV-Vis-NIR system. Solid films, powders and coatings need an integrating sphere. Modular fiber-optic spectrometers fit process lines and OEM use, while microplate readers serve high-throughput assays. Compare bandwidth, stray light at 220 and 340 nm, photometric range, baseline flatness and software features. Specify temperature control if thermodynamic or enzyme kinetic measurements are planned.