Apollo TLS Series

Tuneable Light Source Systems

The innovative design of our light sources allows for straightforward alignment with our ATLAS monochromator-spectrograph series to produce a powerful tuneable light source system – the APOLLO TLS SERIES. With a range of light sources and monochromators available, a highly customisable tuneable light source can be created to meet your power and resolution requirements.


Tuneable light sources are commonly required for a wide range of optical spectroscopy applications, including for example: in physics, chemistry, biology, environmental, quantum efficiency, and spectral responsivity measurements. The innovative design of our tuneable light sources, in a fully modular yet integrated manner, allows straight forward adjustment of the configuration and accessories without the need for challenging changes to be made in order to accommodate different application needs.

The APOLLO TLS series are versatile tuneable light sources of high resolution monochromatic light from the ultraviolet to near infrared. Tuneable light sources comprise three main components: a light source, a monochromator for wavelength selection, and suitable accessories for light delivery. Every TLS we manufacture is pre-aligned, calibrated and tested as a system.

APOLLO TLS300-X600 – Tuneable light source comprising a monochromator with 300mm focal length from our ATLAS series coupled with our APOLLO X600 xenon light source.

  • Highly stable xenon, tungsten and deuterium light sources
  • Optimised light path to maximise light output efficiency
  • Pre-aligned, calibrated and tested to ensure straightforward set-up
  • Output bandwidth can be adjusted continuously
  • Robust and easy to use software control
  • Filter wheel, shutters, optical monitors and other accessories available
  • System supplied as standard on an optical baseplate
  • On-site installation and training available

The Light Source

Continuum light sources such as xenon arc, tungsten halogen and deuterium lamps are commonly used as TLS sources and are coupled to short to medium focal length monochromators that act as tuneable wavelength selectors. The lamp and its power supply are particularly important as they define spectral range, optical stability power levels as well as the spectral smoothness of the optical emission:

Xenon Arc Lamps: 200 to 2500nm

  • Intense continuum output with some spectral lines in visible and shortwave infrared regions
  • Small, high radiance arc with “sun-like” emission spectrum
  • Continuous and pulsed lamp options available

Tungsten Halogen Lamps: 350 to 4000nm

  • Broad band, smooth emission spectrum with highly stable output
  • Long lifetime and relatively inexpensive

Deuterium Lamps: 115 to 400 nm

  • Smooth continuous UV spectrum (above 170mm) with almost no visible to infrared light
  • Shortest UV available wavelength
  • Often used for UV Spectroscopy
The Monochromator Depending on the application, a number of possibilities are available for tuning the light output of a broadband radiation source, including electrical and mechanical tuneable optical filters, narrowband filter arrays and grating based monochromators – the latter being the most versatile. The Camlin Photonics ATLAS series of Czerny-Turner monochromators are ideal wavelength selectors and scanners. With multi-grating mounts and wide range of grating choices, as well as a range of slit modules for fixed, manual or motorised adjustment, they form the cornerstone of low stray light, high throughput tuneable light sources. The most common monochromator for TLS system is the ATLAS 300 which is an ideal compromise between the lower cost ATLAS 150 and the higher performance ATLAS 500 and ATLAS 750. Our monochromators can also be supplied In double monochromators configuration for significant improvement for stray light rejection. For example, the double ATLAS 300 configuration improves stray light to 1:1010
ATLAS Monochromators

  • High levels of wavelength position repeatability and accuracy – critical in a tuneable light source system
  • Modular slit and port configuration allows selection of input and output ports with fixed, micrometer adjusted or motorised bi-lateral knife edge slits
  • Up to two input light sources can be coupled with software control for selection of each
  • Extensive range of high quality gratings mounted on interchangeable grating turrets on precision kinematics mounts
  • Shutters (solenoid and high speed) and motorised output steering mirrors available

The Accessories

The monochromatic light needs to be delivered to the application. At Camlin Photonics we offer a wide range of accessories:

  • Fibre optics F/# matcher for SMA or Liquid Light Guides
  • Integrating Spheres
  • Sample chambers and detectors
  • Beam Splitter and reference detectors
  • Order sorting filter wheel and filters
  • Output collimator for customer specification
  • Custom optical interface can be supplied if required

Our tuneable light source systems are supplied with an optical base plate as standard.

Software Control

With a straightforward user interface, our tuneable monochromatic light sources are easy to operate and control, including control of additional accessories selected. Key software features include:

  • Wavelength selection
  • Grating switch
  • Canning parameters such as start and delay timer, etc.
  • Order sorting filter control
  • Motorised entrance and exit slits
  • Input and output port selection via motorised steering mirrors
  • Shutter control

A serial command list for essential functions are available for user’s own programme control.


Our tuneable light sources are supplied in a modular configuration allowing the user to select both the light source with the appropriate power and spectral range; and the monochromator with appropriate focal length and resolution. With a wide range of available accessories, the system can be further designed bespoke for the user application needs.


Light Source

Camlin Photonics provide a range of light sources all of which can be integrated into our tuneable light source system: xenon short arc lamps, Tungsten Halogen lamps or Deuterium lamps. With a range of output powers, the appropriate light source for your application needs can be provided. In addition, our xenon lamps can be supplied in either continuous or pulsed mode.


Our tuneable light sources utilise our ATLAS series monochromators. Typically, a 300mm focal length monochromator (ATLAS 300) meets most application requirements, but 150mm, 500mm and 750mm focal length monochromators are also available. Our monochromators can also be supplied in double monochromator configuration to improve stray light performance.

Input & Output Ports

Our monochromators have choice of two input and two output ports. Typically, systems are configured with a fixed steering mirror (as illustrated above) to allow for the light source to be set at right angles to collimating main mirror and, with a similar arrangement on the output side, the system is set up in the 180o configuration shown. A motorised steering mirror on the input side allows for the option to mount two light sources with the motorised mirror selecting which source is to be used. Similarly, choice of fixed or motorised steering mirrors allow the output port(s) to be selected.

Diffraction Gratings

An interchangeable grating turret is provided on a high precision kinematic mount to allow precise wavelength selection accuracy and repeatability. The ATLAS 150 has a dual grating turret whilst the ATLAS 300, 500 & 750 models have a triple grating turret.


Precision micrometer adjusted bi-lateral knife edge slits on the input and output ports as standard. Fixed and software controlled motorised slits are also available.

Adaptors & Accessories

A wide range of accessories are available such as order sorting filter wheels and filters, fibre optic and liquid light guide adaptors, integrating spheres, detectors etc. Optics (mirrors and gratings) can also be upgraded to gold coated to improve reflectivity in the infrared.

Application Example

Tuneable light sources have many applications from photovoltaic characterisation and charge transport studies to optically and infrared stimulated excitation spectroscopy and fluorescence microscopy.