>I am trying to give some lighting effect on screen using the following code.
>
>

>FOR I=1 TO 500
>IF MOD(I,2)=0 
>_screen.BackColor= RGB(255,255,255)
>ELSE
>_Screen.BackColor= Rgb(60,60,60)
>ENDIF
>ENDFOR
>_Screen.BackColor= Rgb(60,60,60)
>

>
>Will in effect my screen or monitor in long term, Is there some code that could give me a Photo copier Effect ?

I don't think so - but it may infect the brain with a specific delusional disorder - symptom: continuously uttering religious blah no one understands - the orator included