DSM 20 CD

Far UV and visible [170-700 nm]

The model 20 uses the the new DeSa subtractive double grating monochromator for selecting and scanning the wavelengths. This tiny 7-sided monochromator uses two huge 40 x 45 mm gratings for outstanding light throughput, even down to the lowest wavelengths. These holographically blazed gratings can be for ultraviolet, UV/Vis, visible, Vis-NIR, or NIR. All associated light sources and detectors will be selected by Olis to be compatible with this blazed grating range. The spectral resolution is 0.5-5 nm, based on the slit width used; slits are interchangeable fixed slits of 0.5, 0.6, 1.24, and 2 mm wide, with other sizes available by special request. Like the Olis DSM 17, it can be enhanced to support scanning (or fixed wavelength) excitation and fixed wavelength emission; it is slightly superior to the model 17 in its excitation intensity performance.

DSM 17 CD

UV, visible, extendible to NIR [185-800 nm or -1700 nm or -2500 nm!]

The model 17 uses the Cary 17 prism + grating monochromator. Only this model of the three DSM models provides the option of computerized slit width adjustment during scanning (as opposed to automatic high voltage adjustment and fixed slit width). This monochromator supports NIR detection to 1700 nm (optionally to 2500 nm) using large area (12.5 mm²) InGaAs detectors with unique and innovative preamplifier circuitry. When enhanced for fluorescence applications, the model 17 is usable as a scanning excitation, fixed wavelenth emission syste. This model is capable of angstrom resolution throughout most of its range.

DSM 1000 CD

Far UV to visible, extendible to NIR [167-1700 nm]

The model 1000 uses the patented DeSa subtractive double grating F/ 4.4 monochromator. This model provides you with everything: most light throughput, easiest modularity, widest useful spectral range, and rapid-scanning potential (to 62 CD scans per second!)¹. Mechanical grating mount allows 8 steps/nm, so that the 2400 line grating used in for protein secondary structure work provides in a spectral range of 170-450 nm and a resettability of 0.125 nm/step. Optimizing the DeSa monochromator for nearly any spectral range, spectral resolution, and speed is possible without optical realignment or any calibration concerns. The monochromator supports NIR detection to 1700 nm (optionally to 2500 nm) using large area (12.5 mm²) InGaAs detectors with unique and innovative preamplifier circuitry. The addition of a scanning emission monochromator adds rapid-scanning, scanning, or fixed wavelength excitation with scanning or fixed wavelenth emission detection. For Olis clients who want the most from their spectrophotometer, this is the model of choice. This is the most expensive CD in the world and inarguably the best for CD stopped-flow and other extremely difficult and/ or fast measurements.