How to get UNIFORM energy distribution with G4GeneralParticleSource

Hello all!

I would like to use G4GeneralParticleSource() to produce UNIFORM distribution of optical photons in WL rangle 200-1000nm. I try to use the code like this in :

PrimaryGeneratorAction::PrimaryGeneratorAction() : G4VUserPrimaryGeneratorAction()

fGPS = new G4GeneralParticleSource();

// set energy distribution
G4SPSEneDistribution* eneDist = fGPS->GetCurrentSource()->GetEneDist();
eneDist->SetEmin( nm2eV(1000) * CLHEP::eV);
eneDist->SetEmax( nm2eV(200) * CLHEP::eV);


but inctead of UNIFROM distribution I get something like EXPONETIONAL.

Please advice how to do that.
What is a real meaning of “SetInterCept()”?? Could I set to 0,1,2… etc.
Unfortunately, I now found any clear explonations in “Application Develompent Manuals”. There are only few presentations on internet where it was demonstrated how it should work, but without
any explonation how to calculate probability of given energy.

Sincerely Yours,