Usually monochrome monitors are in two color one for display image & one for background but the monochrome generally indicate black & white image.
while color TV has three guns red, green & Blue. Varying these tubes give you a full spectrum of color. So television can transmits image in color called color television and a television that transmit image into black & white are called monochrome.
Read this review before you buy product it helped you to better understand of color monitor & monochrome monitor.