Fibre optic lighting provides an extremely flexible tool kit to light many different types of project in a myriad of ways. The RobLight Lux Calculator completes this kit with a tool that calculates the light output of RobLight luminaires with Light Generator and customised Fibre Harness.

It is simple and quick to use,  just fill in your selection – fitting, light generator, fibre type, fibre length and number of tails – and instantly get the corresponding lux values, beam angle and beam diameter.

Registered users can also generate IES files to use in professional light planning software programs.





Lux Calculator is available for installation on Window machines.  To install, simply double click on the downloaded file and follow the prompts.  Depending on your system set up you may receive messages to answer in line for your security policy.  Step by step guide 

Once installed and configured, the calculator will present a screen with 3 sections: Light Generator, Harness and Fitting. 


Select from drop down lists

Light Generator type

Variant by LED colour and Ra index

PC size  = Polyconnector or Common End



Fibre Type
Tail diameter Size
Fibre variants
Number of Tails
Tail Length

Calculator will indicate parameters for the tails and warnings if limits are exceeded

As the detail are changed, The Polyconnector fill % in the Light Generator section will be updated.



Select Fitting / Luminaire

Calculator will indicate the output in a cone diagram format at different throw distances.

For longer distances, enter the required throw into last line of table.

For luminaires with focus lenses, the beam angle can be adjusted by sliding the control bar

Adjusting the Harness tail size and length will adjust the output intensity and beam angles

For calculating outputs for multiple fitting types, simply select the tails sizes, lengths and fitting types in turn and note the outputs.


For registered users, the enhanced version of Lux Calculator provides some additional information and can generate IES files for selected configuration.

If these features are hidden, press the button in middle of the screen 







The Light Generator screen shows a Port Scan and Uniformity factor.  The Port scan is an indication of the relative light output of the generator into fibres as offset from the centre of the Common End (Polyconnector). For most RobLight  LED Generators the output is relatively uniform across most of the diameter, reducing the need for randomising to maintain uniformity.  For more fully filled harness, the Calculator will prompt for randomised common end and in some cases suggest contacting sales team for assistance.

The selected configuration can be saved in IES format for use in professional light planning software programs or for viewing in IES viewer, or  Dialux LDT Editor