Sample surface, the amount of light from the light emitting device is too bright and too dark to hide the light of the well, the picture on the amount of light of the lack of it was not so.
The sample surface is lighter too light-emitting device and light from being too dark to make it look bad, the lack of light as long as the picture is unclear.
samples of the surface radiation is too bright, Light Emitting Diode device safety, security, and too dark, due to lack of radiation, Burns did not clear.