An object of the present invention is to reduce the brightness of {HEAD ~ the background} to improve {TAIL ~ the contrast} 
An object of the present invention is to reduce the brightness of { HEAD ~ the background } to improve { TAIL ~ the contrast }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL