Capture up to 3,000 Scans per Second
The newest Ocean Optics spectrometer, Ocean FX, is distinguished by features such as a high-sensitivity CMOS detector, onboard spectral buffering and Ethernet communications. But perhaps most exciting is the spectrometer’s remarkable acquisition speed – up to 3,000 scans per second, depending on the performance of its operating software and the operating system and computer to which it is connected.
High Speed Acquisition and the Need for Speed
The combination of rapid acquisition speed and a minimum integration time of 10 µs makes Ocean FX especially attractive for applications involving high intensity output, transient events and reaction monitoring. Here are some example application areas.
High Intensity Light Sources, Plasmas
With the Ocean FX spectrometer, users can more easily avoid saturating the detector in high light level measurements by integrating over much briefer periods – microseconds versus milliseconds. For example, here’s a comparison of the calibrated saturation intensity for an LED measured with a CCD linear array spectrometer and with the Ocean FX:
In addition, Ocean FX captures more spectral information over a shorter period of time, contributing to better results. The more scans to average, the more complete the story the data reveals.
Figure 1. We used a CCD array spectrometer (350-1000 nm) at 1 ms integration time to measure a 532 nm LED. The spectrometer was set for 20 scans to average.
Figure 2. An Ocean FX-VIS-NIR spectrometer (350-1000 nm) at 10 µs integration time measures a 532 nm LED. Spectral averaging is set for 100 scans to average.
High Speed Sorting, Industrial Production
Ocean FX delivers more reliable results and is more easily integrated into a wider range of environments. For example, in high speed sorting applications, the spectrometer’s high scan rate and Ethernet communications mitigate some of the trade-offs associated with other types of spectrometers.
This combination is especially useful for absorbance/transmission and color measurements, where Ocean FX captures spectra for multiple samples as they move down the line. Food sorting and grading are among the potential applications (Figure 3); in these cases, the addition of chemometric tools could enable even more sophisticated analysis of sample type, quality and other parameters. What’s more, Ocean FX is much less expensive than traditional benchtop instruments and is reproducible in large volumes for OEM customers.
Transient Events, Spectral Artifacts
Ocean FX is well suited for high speed applications like protein fluorescence kinetics and other chemical reactions. In certain reaction kinetics monitoring applications, the onboard buffering feature of Ocean FX offers an additional advantage: the ability to store up to 50,000 spectra, ensuring no data points are missed during critical stages of the reaction.
Laser characterization and light measurement also benefit from the speed of Ocean FX. With lasers, fast sampling makes it possible to measure higher frequency pulses over shorter integration periods, and to stay in phase.
Ocean FX is very well suited to record flicker in home lighting products. Flicker is any modulation of the light output, and occurs in incandescent sources, fluorescent lights, LEDs and other sources. Because these spectral artifacts can affect light source performance and potentially cause eye strain and other discomfort, researchers and manufacturers seek ways to make more efficient, reliable flicker measurements.
We conducted several flicker measurements using an Ocean FX-UV-VIS-ES (200-850 nm) radiometrically calibrated spectrometer. Integration time was set to 100 µs, a cosine corrector held against the light source, and continuous spectra recorded for three seconds.
Here’s an example where we measured a fluorescent bulb in a lighting fixture. After we recorded all the spectra, corrected for dark and determined irradiance at the observation spot, were able to determine the bulb oscillation frequency by wavelength. In Figure 4, we cut the spectra at selected wavelengths to get time traces showing the spectral irradiance at certain wavelengths in time.
Figure 4. Ocean FX allows users to determine spectrally dependent flicker values, such as these highly wavelength dependent values for fluorescent lights.
With more sophisticated analysis, users could extract oscillation amplitudes, phase shifts, and potentially, spikes or drop-outs. In our testing, we found oscillation amplitudes for Hg lines and phosphorous emissions in fluorescent lighting, and in white LEDs and halogen lights. Color temperature also can be determined.
Other Application Possibilities
- Cavity-ringdown spectroscopy
- Color measurement in industrial settings
- Laser induced breakdown spectroscopy
- Process monitoring and control
- Thin film thickness measurements