A full-screen optical component, applied to an electronic device, wherein the electronic device comprises a display screen , the full-screen optical component comprises a backlight module , an active light sensor , and a dimmer configured to adjust an angle of light emitted by the active light sensor , and the display screen and the active light sensor are located on two opposite sides of the backlight module ; the backlight module comprises a first prism film and a second prism film stacked on the first prism film , the first prism film comprises several first prisms disposed in parallel, the second prism film comprises several second prisms disposed in parallel, and a long axis of the first prism and a long axis of the second prism are perpendicular to each other; and the first prism comprises a first in-light surface and a first out-light surface , the second prism comprises a second in-light surface and a second out-light surface , and a display surface of the display screen , the first in-light surface , and the second in-light surface are disposed in parallel; the active light sensor comprises a sensor and a light emitter , and the sensor is configured to sense a reflected light signal of light emitted by the light emitter ; and the dimmer is configured to direct the light emitted by the light emitter to the first in-light surface at a first incident angle that is inclined relative to a vertical direction, so that the light is then emitted from the first out-light surface after being refracted by the first prism , enters the second in-light surface at a second incident angle that is inclined relative to the vertical direction, and is emitted from the second out-light surface after being refracted by the second prism, so that the light passes through the display screen at a vertical angle. the backlight module comprises a first prism film and a second prism film stacked on the first prism film , the first prism film comprises several first prisms disposed in parallel, the second prism film comprises several second prisms disposed in parallel, and a long axis of the first prism and a long axis of the second prism are perpendicular to each other; and the first prism comprises a first in-light surface and a first out-light surface , the second prism comprises a second in-light surface and a second out-light surface , and a display surface of the display screen , the first in-light surface , and the second in-light surface are disposed in parallel; the active light sensor comprises a sensor and a light emitter , and the sensor is configured to sense a reflected light signal of light emitted by the light emitter ; and the dimmer is configured to direct the light emitted by the light emitter to the first in-light surface at a first incident angle that is inclined relative to a vertical direction, so that the light is then emitted from the first out-light surface after being refracted by the first prism , enters the second in-light surface at a second incident angle that is inclined relative to the vertical direction, and is emitted from the second out-light surface after being refracted by the second prism, so that the light passes through the display screen at a vertical angle. <EOS>