News | May 27, 2005

Ocean Optics Introduces Modular High-sensitivity Spectrometer For Raman Analysis

Dunedin, FL — The Ocean Optics QE65000 Spectrometer is a remarkably high-sensitivity modular spectrometer for Raman analysis and other low-light level applications such as fluorescence, DNA sequencing, thin film reflectivity and astronomy. The QE65000 can achieve up to 90% quantum efficiency with high signal-to-noise and rapid signal processing speed. A user can optimize the spectrometer's range and resolution by selecting from Ocean Optics gratings 14 gratings and seven entrance slit options.

The modular QE65000 features an SMA 905 connector and accepts light transmitted through an optical fiber. This flexibility enables users to make Raman measurements using their own laser and probe configuration.

Ocean Optics makes available a series of fiber optic Raman probes, each providing complete optical filtering of the Rayleigh line and high signal collection in a compact, rugged design. Probe models are available for laboratory, industrial and environmental applications and are available with 514 nm, 532 nm, 633 nm, 670 nm 783 nm, 785 nm and 830 nm bandpass filters, with laser filtering to 108. The QE65000 has a Hamamatsu back-thinned detector that provides 90% quantum efficiency (defined as how efficiently a photon is converted to a photoelectron). The detector's 2-D arrangement of pixels, 1024 horizontal x 64 vertical, is responsive from 200-1100 nm. Its columns are binned, or summed, inside of the detector prior to the readout process to improve the signal-to-noise ration by minimizing readout noise. Additionally, the detector can be cooled down to -20ºC with the onboard TE-cooler to reduce dark noise. The reduction of noise and dark signal allows integration times of up to 15 minutes, which greatly enhances the spectrometer's detection limit of low-level Raman signals. The 2-D detector makes more efficient use of light regulated by the height of the entrance slit, adding to the system's sensitivity.

The combination of the spectrometer's low-noise detector, electronics and 16-bit A/D converter delivers a dynamic range of 25000:1 and a signal-to-noise ratio of >1000:1.

The QE65000's onboard module has 10 user-programmable digital I/O lines for interfacing to other equipment; and a pulse generator for triggering other devices. Users can use the I/Os to pulse a laser, stop/start a process, and send a message/alarm during the spectrometer's integration period. The spectrometer's operating parameters can be controlled through software. In fact, wavelength calibration coefficients unique to each spectrometer are programmed into a memory chip right on the spectrometer.

TheQE65000's high-speed electronics have been designed for considerable flexibility in connecting to various modules and external interfaces -- including PCs, PLCs and other embedded controllers -- through USB 2.0 (backwards compatible to USB 1.1) or RS-232 communications. Its USB 2.0 interface enables full spectral scans into memory every 7 milliseconds.

The QE65000 draws its power from the USB interface, but requires a +5 VDC external power supply for the TE-cooler and to operate the spectrometer via an RS-232 interface.

In addition to its modular QE65000 Spectrometer, Ocean Optics makes available fully integrated Raman systems. The RSL-1 is a handheld Raman system that's ideal for on-site applications such as materials analysis. The R-3000 is an integrated low-resolution Raman system for molecular spectral analysis of aqueous solutions, powders, surface media and gels.

About Ocean Optics
Ocean Optics is a leading supplier of solutions for optical sensing—fundamental methods of measuring and interpreting the interaction of light with matter. We enable diverse applications in medical and biological research, environmental monitoring, science education, and entertainment lighting and display. Our extensive line of complementary technologies includes spectrometers, chemical sensors, metrology instrumentation, optical fibers, and thin films and optics. Recognized as the inventor of miniature fiber optic spectroscopy, we?ve sold more than 50,000 spectrometers worldwide since 1989. Ocean Optics is part of the Halma Group of safety and detection companies, a United Kingdom-based multinational corporation with 2003 sales of nearly $550 million.

Source: Ocean Optics, Inc.