CoolLed pT-100

The latest technology for transmitted illumination


The pT-100 is a compact and simple-to-use LED illumination system for transmitted light applications, including brightfield, darkfield, DIC, Dodt gradient contrast and phase contrast.

The system is available in four variants to bring the benefits of LEDs to modern laboratories. A broad white system provides a safer and convenient alternative to halogen by reducing harmful UV exposure to the eyes and is ideal for long hours spent at the microscope, while three narrow bandwidth options (525, 635 and 770 nm) optimise image quality through increased contrast. The pT-100 WHT and pT-100-770 nm are also available as variants with a 3 mm liquid light guide attachment.


Utilising the highly successful pE-100wht technology, we have further developed our LED solutions for Transmitted Light Applications with the pT-100 range.  Whether you’re looking for a broad white 100 W halogen replacement or want to optimise the quality of your images through the use of narrower spectrum wavelengths, the pT-100 can meet your needs.

CoolLED LED illumination technology offers a host of benefits over halogen systems, with instant on/off and irradiance control in 1% steps from the ergonomically designed manual control pod which can be positioned close at hand. Remote control is also available via a TTL trigger.

A true 100 W Halogen replacement: pT-100-WHT

Laboratories familiar with halogen lamps will find that CoolLED’s broad white achieves results which make the move to LEDs simple and apparent.  Colour temperature remains constant as irradiance is increased which makes colour balancing unnecessary and improves standardisation between sessions. Samples will appear identical even though irradiance could be up to five times greater.

In addition, the pT-100-WHT does not produce unwanted light in the UV which makes it safer and more comfortable, as risk of eye damage is significantly lower.

Narrow bandwidth solutions eliminate background noise

White light LED systems using a phosphored LED can be a source of background noise when used as a transmitted light source, which reduces image contrast. Narrow bandwidth illumination systems remove this background source to improve image quality and enhance analysis – even in thicker samples and applications requiring infrared light.

  • Higher contrast images: pT-100-525
    Narrow bandwidth at 525 nm is optimised for the spectral response of most scientific cameras and reduces background noise from a phosphored LED.
  • Revealing details in thick samples: pT-100-635
    Narrow bandwidth at 635 nm provides deeper penetration, which is excellent for revealing detail in thicker samples.
  • Infrared illumination of thicker samples: pT-100-770
    Narrow bandwidth at 770 nm provides deeper sample penetration techniques that require the use of infrared light.

The pT-100 WHT and pT-100-770 nm are available with a 3 mm liquid light guide rather than using a direct attachment adaptor. This enables the Illumination System to be used on microscopes which just have a liquid light guide input, the collimating optics being an integral part of the microscope.


  • Comfortable operation and reduced risk of eye damage as no unwanted UV
  • Spectral performance matched to 100 W halogen, creating consistent images
  • No variation in colour across irradiance range, removing the need to colour balance
  • Replaces 100 W halogen lamp housing on most current and older microscopes – quick & easy exchange


  • A phosphor-free illumination centred around 525 nm optimised for the spectral response of most scientific cameras
  • Improved image contrast compared to white light source


  • A phosphor-free solution for brightfield imaging with a peak of 635 nm providing deeper penetration in thicker samples
  • Reduced phototoxicity of light-sensitive samples


  • A specialised solution for IR contrast techniques such as DIC, Dodt contrast etc.
  • Centred around 770 nm provides the optimal output for deeper sample penetration techniques requiring infrared light

The system comprises a pT-100 LED Light Source, control pod, and power supply.

Power requirements
100-240 V a.c. 50/60 Hz, 0.7A

Power consumption
1 W (standby)
20 W (full irradiance)

pT-100 Light Source (direct fit): 66 mm (diameter) x 128 mm(l) Weight 0.42 kg
pT-100 Control Pod: 102 mm(w) x 110 mm(d) x 50 mm(h) – Weight 0.55 kg
pT-100 Power supply: 55 mm(w) x 95 mm(d) x 40 mm(h) – Weight 0.19 kg

Environment & Safety

  • Mercury-free & Laser-free
  • Energy Efficient
  • Long lifetime
  • No bulb replacements
  • Quiet operation
  • No special disposal regulations or issues
  • Reduced risk of eye damage.  Care should be taken when viewing samples using the microscope eyepiece while the transmitted light source is switched on. Users should select the lowest irradiance setting on the pod before using the eyepiece and increase irradiance as necessary.


Industry-leading 36 months.