The Model TEO200 benchtop FTIR spectrometer is a low cost Fourier transform infrared spectrometer that employs a number of unique features to achieve high performance from such a compact size. At just 385x265x160mm , it is one of the most compact FTIR systems on the market today.

The TEO200 is unique in terms of its optical geometry and software/firmware design. The optical geometry is simplified by employing a new and remarkably compact Michelson self compensating optical system that eliminates many of the optical alignment problems found in conventional linear and pendulum type optical interferometers. For example, the TEO200 design avoids the use of conventional corner cube optics and dynamic alignment. In practical terms, the instrument can be used inside a research laboratory, or even as a mobile unit in outside environments. Its software and firmware design is also tightly coordinated which significantly reduces overall data acquisition and computational time.

The sealed, desiccated enclosure of the TEO200 eliminates the need for continuous dry nitrogen purging during operation. Other notable features include an air cooled IR source as oppose to water cooled, and the interferometer mechanical bearing does not require gas supply. There are however, three dry nitrogen gas inlets on the rear of the spectrometer for the purging of the detector compartment, sample compartment, and interferometer compartment from moisture, carbon dioxide and other gases.

Instrument Performance
The TEO200 FTIR offers high S:N ratios and can provide SNR up to 12000:1. Resolution in the infrared is available and programmable up to 32 cm^-1. The overall wavelength range is 7000 to 400cm^-1 (IR) or 15000 to 3850 cm^-1 (NIR).

Built-In Sample Compartment
A large transmission sample compartment is built into the instrument to accommodate most typical sample handling requirements relating to FTIR spectroscopy. The sample compartment accommodates various sampler holder inserts in transmission and reflectance modes that accepts slide-mounted samples, liquid samples in cuvettes, and gas samples. In reflectance mode, sample holder inserts for fixed grazing angle reflectance, adjustable specular angle reflectance, and ATR reflectance are available. This unique compartment can also accommodate the wide range of accessories supplied by specialist accessory manufacturers such as an ellipsometer insert for thickness measurements. Overall dimensions of the sample compartment are 200mm (width) x 235mm (depth) x 154mm (height) The optical axis of the single transmission beam is 74.5 mm above the base of the sample compartment and there is free space of 90 mm above the optical axis to the underside of the lid.

Custom and External Sample Chambers
The built-in sample compartment can accommodate custom sample holders. Overall dimensions of the sample compartment is 200mm (width) x 235mm (deep) x 154mm (height). The optical axis is 74.5 mm above the base of the sample compartment and there is free space of 90 mm above the optical axis to the underside of the lid. If this space is not ample, Sciencetech can design a custom sample chamber external of the instrument using fibers. Please inquiry to our Sales Applications Specialists at sales@sciencetech-inc.com for custom sample holders and external sample chambers. The development of such a sample holder or chamber will be quoted separately.

IR Source
The radiation source is situated on the back side of the spectrometer. The IR source is a high intensity long life device made from a special alloy wire to achieve excellent instrument sensitivity and stability. Neither cooling water nor purge gases are required for this unique low power infrared source. The source is housed so as to achieve a very high operating temperature with minimum power. The colour temperature of the source is about 1200 °C and the heating power is about 15 W. The applied voltage is stabilized using a feedback loop driving a switched mode power supply.

Extended Wavelength Ranges

In order to facilitate the use of more than one beam splitter or detector, provision has been made to interchange the beam splitter and detector assemblies allowing the Sciencetech TEO200 to be used at any wavelength from 15000 to 400 cm^-1.

• KBr 7,000 to 400 cm^-1
• ZnSe 5,000 to 500 cm^-1
• CaF₂ 10,000 to 1,000 cm^-1
• Quartz 15,000 to 3,000 cm^-1

Please note that beam splitters range is subject to coatings

KBr Beam Splitter Spectral Range Clarification

The spectral range of the TEO200 FTIR is governed by the spectral range limitation of its beam splitter as its pyroelectric detector spectral range is so wide that it is not the limiting factor. The KBr beam splitter has a published spectral region of 7800-380 cm^-1, but we have found the working region to be only 7000-400 cm^-1.

Detector Options
The detector compartment can be purged using dry nitrogen by way of a purge connector at the rear of the spectrometer. The standard detector is a selected high sensitivity DLATGS pyroelectric design providing the highest possible signal to noise for all but the most demanding applications. However there are many applications in infrared spectroscopy where high resolution analysis is required for materials with high absorption characteristics and for these applications cryogenically cooled MCT detector options are available each with a specific wavelength range. In case of NIR spectral region two types of photodiodes are available: Si and InGaAs.

Software
Windows software is supplied on CD and provided with each system shipped. The software includes features for all standard analytical requirements including manipulation of spectral data, instrument control, plotting with preview on the screen plus many others. Also included are several facilities for analytical modeling of interferogrammes or spectra, with smoothing, and baseline correction, interactive editing and data manipulation. Also spectral subtraction, mixture subtraction, smoothing derivatives, plot with preview etc. Data input and output is possible in ASCII or JCAMP. Other commercial programs can be used including Thermo/Galactic GRAMS (See ThermoGalacticGRAMS.pdf)
for features such as Library Search. The software program is written in 32 bit protected mode. Our unique software has been designed specifically for multi function applications, it is easy to use and it is provided free of charge. The utility of the software program can be extended by adding other commercial programs such as search, component identification, Kramers Kronig Transform, Chemometrics, etc. to suit individual requirements.

Air Cooled Infrared Source
Our Infrared source is a long lifetime and trouble free operation device. The reason is simple in that our design achieves excellent wavelength emission characteristics and very high stability. The colour temperature of the source is about 1200°C. In the NIR region a quartz-halogen lamp is used.

Desiccated and Sealed Interferometer
The Sciencetech TEO200 series of instruments employ a sealed and desiccated interferometer and detector compartment, ensuring high spectral integrity with low levels of water vapor within the interferometer. We also offer a version (200-XZ) that employs a ZnSe moisture insensitive optics to be impervious to water vapor and can be used to advantage in serious tropical environments. Provision is made for purging should this be of interest to the user. Near infrared version (200-XN) employs a fused silica optics and is insensitive to any influence of water vapor.

Technical Specifications
Spectral range Spectral Region: 7800-380cm^-1 (7000-400 cm^-1 nominal)
Resolution (Unapodised): 0.5 cm^-1
Wave Number Precision: 0.01 cm^-1
Ordinate Precision: 0.1 - 0.01 %T
Interferometer: Michelson type, self-compensated for tilt and shear
Beam Diameter: 38 mm
Aperture Ratio: f/3.2
Operation Mode: Single Channel
Throughput: 0.015 cm²sr
Beam Splitter: KBr Substrate, Multilayer Coated
Option: ZnSe Substrate
Scanner: Pendulous Scan
Scanning Rate: 2 mm OPD/s,
Frequency Reference System: He-Ne Laser, 633 nm
Sampling: Conventional
Sample Compartment: single beam, 250mm (width) x 250mm (depth) x 140mm (height)
Beam Size: 10 mm - Center Focus, Beam Center 74.5 mm Above the Base plate
Input Port (Option): Entrance Port for Radiation from External Sources
Source: Coil form, Air Cooled
Detectors: Standard: DLATGS Pyroelectric Option: LN2 MCT
Atmosphere: Sealed, with Ports for Dry Nitrogen or Air
A/D converter: 16 bit, 100 kHz
Computer: IBM PC Pentium or Similar
Operating system: Windows 95/98/XP
Display: SVGA (1024 x 768 pixels recommended)
Dimensions (w/d/h): 590/390/190 mm
Weight: 24 kg
Power Consumption: 100 - 240 VAC, 40 W, 50/60 Hz
12 VDC
Temperature Environment: 18°C to 28°C
Humidity Environment: Below 65%, Non-Condensing