LCD device and OLED display device

A liquid crystal display (LCD) device, comprising:

• a backlight module disposed at a bottom of the LCD device;
• a display module disposed on the backlight module and comprising a color filter plate, a top polarizer disposed above the color filter plate and away from the backlight module, a black mask layer disposed on a side of the color filter plate and located between the color filter plate and the top polarizer, and a fingerprint recognition unit disposed on a side of the color filter plate away from the black mask layer, wherein the black mask layer is a black matrix or is made of a black metal, takes up part of an aperture area of the LCD device, and includes an array of holes pass passing through an upper surface and a lower surface of the black mask layer;
• and
• a liquid crystal lens layer disposed above the display module and comprising an upper substrate and a lower substrate for cell-assembly, and liquid crystal lenses disposed between the upper substrate and the lower substrate, wherein an upper electrode is disposed on a side of the upper substrate facing a direction for the cell-assembly, a lower electrode is disposed on a side of the lower substrate facing a direction for the cell-assembly, and the liquid crystal lenses configure a lens array corresponding to the array of holes of the black mask layer under action of the upper electrode and the lower electrode;
• wherein the liquid crystal lens layer is configured to operate in a lens state when the fingerprint recognition unit is operating, and the liquid crystal lens layer is configured to operate in a non-lens state when the fingerprint recognition unit is not operating.