TLS120Xe High Power Tuneable Light Source (280 nm — 1100 nm)
4 weeks
Details
User Experience
The TLS120Xe features a highly intuitive user interface, consisting of a screen that shows the current peak wavelength and bandwidth, and a dial by which the wavelength can be adjusted. The wavelength dial is programmed with acceleration curves commonly used in computer mice, which allows a fast turn to traverse hundreds of nanometers, while slow turns allow very precise control of the target wavelength. The screen keeps you up to date with the current target, and the TLS moves its grating while you turn the dial, making for a very responsive experience.
A useful additional feature is the ability to switch to white-light mode. This functionality is also easily accessible via this wavelength dial -- if you turn it downwards beyond the lowest wavelength attainable, the TLS transitions to its white-light output mode where the required intensity of white light can be selected.
Output Optics
The TLS120Xe can be ordered with different output fibres or light guides, but this does not restrict you to using this optic. Interchangeable output adapters are available making it quick and easy to switch between different types of fibres and light guides, and custom adaptors are usually simple to manufacture. If your requirements are not listed let us know!
Internal Optics
The TLS120Xe contains a high-powered xenon light source in an ellipsoidal reflector that illuminates a concave holographic diffraction grating mounted on a precision angular stage. The white light from the light source is split into its component wavelengths by the diffraction grating. An output slit selects a range of these wavelengths. Unwanted light from higher diffractive orders is removed by means of order sorting filters mounted on a rotating filter wheel, which also functions as a shutter.
Monitor Photodiode
To optimise the xenon lamp alignment after fitting a new bulb, the TLS120Xe features a photodetector with external SMA thread, by connecting the output SMA cable to the built-in photodetector, the positioning of the bulb can be optimised by measuring the light emitted at the end of the output fibre. The photocurrent is shown on the display... or it can be read via USB!
Electronics
Mains electricity enters the TLS120Xe through a filtered IEC mains socket on the rear, which powers a 300 W switch mode power supply. This provides power to all the internal components, which include precision motor drivers, lamp power supply and an ARM-based control board which handles the high-level communications with the user and steers the electronics.
The lamp is powered by a dedicated constant-current power supply, the same type found in our 610 Current Stabilised Power Supplies, that provides extremely smooth, stable power to the xenon lamp. The ignition of the xenon lamp arc requires a short pulse of 30 kV. The electronics to create this pulse are located in the electromagnetically shielded optical cavity to prevent interference.
Software Control
The TLS120Xe is a smart device that contains all of its calibration data, as well as the algorithms and calculations required to reconfigure itself for a certain wavelength, so minimal work is required externally. To further simplify the control scheme:
- The USB device class is HID, which does not require drivers in any modern operating system, as it is the same class of device used by keyboards and mice.
- The command protocol consists of SCPI-style text-based commands that are very readable. For instance, you can turn your lamp on with the command "LAMP ON". For all the available commands, please see the TLS120Xe communication manual.
- No Bentham software is required on the host computer, but we do provide some software to simplify things. For instance, we publish a crossplatform Python package bendev, which is open source, available with the permissive MIT license, and can be installed with "pip install bendev". A windows SDK with a simple control library and a terminal is also available.
