1. A medicine inspection device, comprising: an inspection unit on which a medicine for inspection is disposed, the medicine being contained in a sachet; an imaging unit capable of photographing the sachet disposed on the inspection unit; and a medicine information detector capable of detecting at least either of a quantity or type of the medicine based on an image obtained by the imaging unit; wherein the inspection unit comprises a backlight capable of illuminating the sachet from backside when photographing, the backlight comprising illumination areas located dottedly per predetermined pitch, and wherein the medicine information detector is configured to implement: a basic image acquisition process for acquiring a basic image for medicine inspection based on a back lit image photographed by illuminating a packaging paper from behind by the backlight; an inspection area defining process for defining an area for inspection by executing an exclusion process of excluding a dot-shaped translucent region contained in the basic image obtained in the basic image acquisition process; an inspection image acquisition process for acquiring an inspection image by extracting an area corresponding to the area for inspection from a back unlit image obtained by photographing same region as the back lit image in a state where the backlight is unlit; and an image inspection process for performing image inspection to detect the medicine quantity or type or both based on the inspection image.