CoolLed pE-4000

  • Research fluorescence
  • 16 selectable wavelengths
  • White mode
  • Advanced mode
  • TTL & USB control



The pE-4000 sets the standard as the universal Illumination System for fluorescence microscopy. The system has 16 selectable LED wavelengths across four channels that can be finely controlled and matched to the filters and fluorophores of almost any microscope, making it the broadest and most versatile illumination system available.

The CoolLED pE-4000 benefits from our award winning sustainable Green technology and delivers enhanced irradiance at the sample plane with a significant reduction in energy consumption, and is supplied with a 36 month warranty.


Advanced control for cutting-edge research

Multiple levels of control are possible, from simple to advanced. A dual mode control pod gives immediate manual control in either White or Advanced modes, where individual LED channels can be individually switched on/off or irradiance modulated.

Alternatively, the USB interface and integration into major microscope software platforms allows complex software control.
TTL control enables capturing high-speed events (<1 ms). Since there is no shutter or filter wheel, without these moving parts, this reduced latency means speed is limited only by the camera. An expansion box is also available for added functionality with multiple BNC connections for remote analogue and TTL control.

For optogenetics applications, alongside the ability to include excitation filters to tune the wavelength to the opsin’s maximum activation peak, an internal function generator controls pulse timing and waveforms.

Improving cell viability

With the pE-4000, it is now possible to prevent artefacts and allow live samples to thrive in experiments >100 hours. Fine control of illumination timing and irradiance with TTL and the function generator minimises exposure, avoiding photobleaching and phototoxicity.

Matching diverse fluorophore requirements

Full filter compatibility and 256 wavelength combinations from 16 installed LEDs (365 nm -770 nm) covers all available fluorophores, which is ideal for multi-user facilities or evolving experimental needs.

Multi-channel experiments with no pixel shift

Up to four channels using distinct wavelengths can be captured with no mechanical movement, preventing pixel shift and allowing the direct comparison of data as in the following experiment:

(A) Representative photocurrent traces of a PhobosCA expressing CA1 cell evoked with different activation wavelengths and shutoff with 595 nm light. (B) Photocurrent traces in the same cell evoked with 460 nm light and shutoff with indicated wavelengths (10 mW/mm2).1

Increased power efficiency

Our unique Wavelength Grouping Concept makes it possible to deliver more power in an efficient four-channel system. As the first company to introduce LEDs into fluorescence microscopy, CoolLED has developed a comprehensive understanding of the complexities of configuring and selecting filter sets for experiments using multiple fluorophores. CoolLED’s innovation comes from recognising that all the fluorophores used in multi-band work can have their absorption bands divided into four separate groups across the spectrum due to the restricted bandwidth available.

DAPI/FITC/TRITC/Cy5 Quad filter excited by pE-4000 at matched wavelengths shown above.


  • Broadest LED spectrum available: 365-770 nm, with 16 LEDs
  • Four channel wavelength-grouping design matches most commercially available dual, triple, and quad filters
  • Removable inline excitation filter holders: no moving parts for fast acquisition
  • Internal function generator for electrophysiology and optogenetics applications
  • TTL and USB interfaces with major imaging software packages allows incorporation into all experimental parameters
  • Analogue inputs for dynamic irradiance control
  • Individual control of selected LED wavelengths reduces background
  • Rapid switching between LED wavelengths enables capture of high-speed events
  • Instant on/off: No shutters required, no warm up or cool down
  • Stable and repeatable: reliable and consistent results
  • Precise irradiance control in 1% steps (0-100%): no ND filters required


  • Pre-sets allow lab manager to match white spectrum to existing filter cubes
  • Simple to fit, simple to use: no alignment, a once only adjustment
  • Wide range of microscope adaptors: fits most microscopes


Power requirements

110-240 V a.c. 50/60 Hz, 2.5 A

Power consumption

Standby (i.e. no LEDs on) : Max 7 W
Single wavelength operation : Max 25 W
Dual wavelength operation : Max 44 W
Triple wavelength operation : Max 53 W
Quad wavelength operation : Max 60 W


pE-4000 Light Source: 150 mm(w) x 22 0mm(d) x 260 mm(h) – Weight 3.5 kg
pE-4000 Control pod: 154 mm(w) x 135 mm(d) x 40 mm(h) – Weight 0.95 kg
pE-4000 Power Supply: 164 mm(w) x 64 mm(d) x 35 mm(h) – Weight 0.58 kg
pE-Expansion Box: 151 mm(w) x 18 mm(d) x 95 mm(h) – Weight 0.34 kg

Environment and Safety

  • Mercury-free and Laser-free
  • Energy Efficient
  • Long lifetime
  • No bulb replacements
  • Reduced risk of eye damage
  • Quiet operation
  • No special disposal regulations or issues

Industry-leading 36 months.