McTriple LE for the best light throughput and spectral resolution in one instrument.
The McTriple LE is a research tool for Raman spectroscopy. Raman instruments are often designed to favor light throughput and sacrifice spectral resolution. Often they are quite small. In reality, many labs may encounter unique spectroscopy challenges. Some that require high spectral resolution and others that require the more light throughput. The McTriple LE is the answer to both requirements.
McPherson's McTriple LE delivers f/4.8 and 0.3cm-1 FWHM spectral resolution in the Visible and provides excellent stray light rejection. The all reflective tunable filter is ideal for Raman spectroscopy to 50cm-1 from Raleigh scatter in the Visible. The McTriple LE uses high quality reflective optics that work over the 185 to 1000-nm* range. It is efficient in the UV. This Raman system is ideal for the weakest samples. It works at f/4.8 and uses fewer reflective surfaces. The McTriple aperture ratio collects about 5X more light!
The McTriple LE optical path is shown below. The primary spectrometer has a (red) f/4.8 optical path as well as a (blue) 0.3cm-1 FWHM path. |
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McPherson's McTriple LE has the following features: The entire optical train uses reflective optics to enable the wide wavelength range without refocusing. The high performance subtractive double pre-monochromator is used for band selection and edge formation. The pre-spectrometer utilizes aberration corrected holographic gratings for best efficiency and imaging. The holographic gratings have high fidelity surfaces further reducing scatter. The slits are continuously adjustable and together with the high precision drive system flexibly tune the image location and optimize rejection.
Specifications
| Focal Length | First stage: 200 mm, Second stage: 200 mm, Third stage: 670 & 1335mm |
| Slit Locations | Axial. Second entrance direct to Spectrograph stage. |
| Slits | 0.01 to 4 mm wide; 2 to 20 mm high |
| Slits (Subtractive intermediate) | 0.025 to 10 mm wide; 0.025 to 10 mm high |
| Slits (Spectrograph entrance) | 0.01 to 4 mm wide; 2 to 20 mm high |
| f / No. | f/4.8 & 9.4 |
| Dispersion | 0.83 & 0.41 nm/mm with 1800-g/mm grating, Spectrograph stage. |
| Resolution | 1 cm -1 & 0.3cm-1 at 500 nm |
| Grating Size | (2X) 40*45mm and (1X) 120 x 140mm; select from many gratings including original (master) high fidelity holographic gratings |
| Drive Mechanism | Sine bar |
| Step Size | 0.0002 nm |
| Wavelength Accuracy | +/-0.2-nm (on counter, with 1200 G/mm grating) |
| Wavelength Reproducibility | +/- 0.005 nm (with 1200 G/mm grating) |
| Focal Plane | 50-mm, multiply dispersion by the width of detector for range |
| Wavelength Range | refer to grating of interest for range |
| Grating | Mechanical Range* | f/4.7 mode CCD Coverage** | f/9.4 mode Resolution at 500-nm*** |
| 300 | 0 to 6000 | 126-nm | 1.6cm-1 |
| 600 | 0 to 3000 | 63-nm | 0.8cm-1 |
| 1200 | 0 to 1500 | 32-nm | 0.4cm-1 |
| 1800 | 0 to 1000 | 21-nm | 0.3cm-1 |
| 2400 | 0 to 750 | 16-nm | 0.2cm-1 |
| 3600 | 0 to 500 | 11-nm | 0.14cm-1 |
* To work through a wide range, eg. 185 to 1000-nm efficiently, more than one grating may be required.
**1-nm corresponds to about...
170cm-1 at 240 nm
40cm-1 at 500 nm
15cm-1 at 750 nm
*** f/9.4 resolution relative to 500-nm scanned with 10-um wide slit