You can't always use a backlight when you want to, but you can achieve a backlight effect using front illumination with the Backlight fluoreSHEET™ by MidOpt! Combine these with an Orange Bandpass Filter and a blue light, and you have a bright white diffused background in a monochrome image.  
 
https://machinevisiondirect.com/collections/backlight-fluoresheet?usf_view=list