Choosing a Portable Raman Spectrometer

---

Sensitivity: More signal, higher throughput, faster measurements

Raman is a low-light technique, which makes every photon precious. A general-purpose compact spectrometer may not have the sensitivity needed to capture sufficient Raman signal without accumulating excess background noise. The ideal portable Raman spectrometer is designed around a few simple principles – collect more light, keep more light, detect more light. We design every Wasatch Photonics portable Raman spectrometer for maximum sensitivity – to collect more signal from weak Raman emitters compared to other spectrometers. Even low concentrations can be measured, thanks to higher signal and cleaner spectra.[su_row][su_column size=”1/2″][/su_column][su_column size=”1/2″][/su_column][/su_row]Wasatch Photonics Raman spectrometer designs use a low f/# (high NA) input to increase light collection, our own patented VPH transmission gratings for maximum diffraction efficiency at all wavelengths, and custom optics to achieve diffraction-limited optical design. This combination yields a superior, high throughput optical bench for low light level applications, which we match to the best detectors for each application. The result? You can collect more Raman signal in a shorter period of time – for better signal-to-noise, lower limits of detection, and faster back-to-back measurements. Learn more about our optical design benefits

Reliability: Robust design, reproducible measurements

A portable Raman spectrometer needs to perform reliably in a variety of different use-case environments, providing consistent spectral data from one day to the next – independent of changes in temperature and movement. We use a transmission-based optical design known to minimize wavelength drift and peak distortion with temperature, as demonstrated below. We also perform shock and vibration testing to ensure our designs are mechanically robust. [su_row][su_column size=”1/2″][/su_column][su_column size=”1/2″][/su_column][/su_row]Analysis of Raman spectra often involves matching to a library or use of chemometric models. This makes low unit-to-unit variability important, especially for OEMs. At Wasatch Photonics, we pride ourselves on high unit-to-unit consistency, and we are committed to providing the appropriate wavelength, wavenumber, and spectral response calibrations and standards to ensure rock-solid spectra. This allows you to achieve better than >99.5% unit-to-unit spectral agreement using Wasatch Photonics spectrometers, as demonstrated by the spectra from seven separate spectrometers overlaid above.  Learn how to collect reproducible Raman spectra

Configurability: More wavelength, sample coupling, and OEM options

A small footprint shouldn’t mean limited options. The configuration of a portable Raman spectrometer influences the strength and quality of its spectra, and its practical fit for each application or use-case. The options & factors to consider include:

• Excitation wavelength: a balance between signal strength and background fluorescence
• Integrated laser: retain the flexibility of a modular system and reduce cost with a built-in excitation laser, or use a fully integrated system for the greatest signal in the smallest footprint
• Spectral range: fingerprint region for identification (<1800 cm^-1) or extended functional range for maximum information (<3600 cm^-1)
• Choice of detector & cooling level: a compromise between cost, dark noise, and power draw/size that depends on signal level and how & where the instrument will be used
• Sample coupling: is the sample solid or liquid? Is a fiber optic Raman probe needed to reach it?
• OEM options: availability of a streamlined, equivalent model for integration into an application-specific instrument is important for OEMs and researchers developing a new product

At Wasatch Photonics, we understand the influence and interplay of each of these factors, and can advise on the best match to your application. In fact, that’s why our portable Raman spectrometer family includes configuration options from 248-1064 nm with a choice of detectors to suit research & OEM applications – all with our signature high sensitivity & speed – to help you get the best data possible in the right form factor for your application. It also makes it easy for you to source multiple Raman needs from one vendor, saving you time and effort so that you can get to the science faster, and providing the consistency needed to easily transfer your software, analysis methods, and learnings from one project to the next.Consistency is particularly important when developing a new Raman-based instrument. Too often, instrument developers are forced to perform proof-of-concept testing on a benchtop instrument initially, then repeat it with a more compact OEM spectrometer, but why waste that time & effort? The high sensitivity of our portable Raman spectrometer line allows you to perform R&D with a compact benchtop unit for the lab, then quickly & easily migrate to the equivalent OEM module for prototyping and production. We call this our ‘OEM by design‘ philosophy. By using the same optical design throughout, you guarantee consistent performance from R&D to launch, which in turn reduces your risk and accelerates your product development.

Ease of use: Intuitive & powerful software, simple setup

Good products are easy to use, and a portable Raman spectrometer should be no different. Look for Raman-specific software that comes with the spectrometer at no additional cost, with an intuitive user interface that makes getting started easy, right out of the box (see how). Software development kits (SDKs) that are available in a variety of programming languages increases compatibility with other systems, your existing software stack, and your team’s personal programming preferences, allowing automation of data acquisition and speeding instrument development. The ability to develop plug-ins compatible with the existing GUI can simplify data analysis and automate application-specific answers. At Wasatch Photonics, we believe software should give you the freedom to collect and analyze your data in the way that works best for you. Our ENLIGHTEN™ spectroscopy software & SDKs were developed by experienced Raman spectroscopists in collaboration with research & OEM customers. It offers features essential for Raman, including control of onboard laser power and detector/measurement parameters, plus corrections for laser wavelength, spectral response, and thermal drift using known standards. It allows you to start each day with the same acquisition parameters, save & recall spectra for later analysis/export, run multiple units, and perform sequential spectra collection easily. We also offer embedded Raman library matching powered by Wiley’s KnowItAll spectral identification engine, complete with the pre-processing steps needed to enhance matching accuracy. Whether you want a quick & easy interface to collect data or SDKs to power your own software, we have you covered. ENLIGHTEN™ is included with every spectrometer and is free for download here. Don’t see a feature you need? Let us know  

Full data transparency: Access to raw data and all data analysis steps

A portable Raman spectrometer should give you full access to your data, in unprocessed form. Many spectrometer manufacturers perform some degree of pre-processing, which in benchtop spectrometers can be automatic. Although this is convenient for some applications, it can limit your ability to understand, control, and modify spectral pre-processing and subsequent analysis. The VPH gratings at the heart of our Raman spectrometers are transparent, and we believe our data collection and processing should be the same. We offer you full data transparency, giving you access to the raw spectrum collected in a variety of file formats, as well as all correction and processing steps thereafter. Our ENLIGHTEN™ software and SDKs are open source, which means you can see, adapt, and customize each step of data processing at the source code level to create your own custom algorithms and software attuned to your specific needs.