Abstract: A light guide plate including a light emitting surface, a bottom surface, a light incident surface, multiple protrusion structures, and multiple grooves is provided. The light incident surface is connected between the light emitting surface and the bottom surface. The protrusion structures are disposed along a first direction and extend toward a second direction. The protrusion structures have a light condensing angle along the first direction, and the light condensing angle ranges from 10 degrees to 40 degrees. The grooves are disposed in the protrusion structures of the light guide plate. The grooves extend toward the first direction. The protrusion structures have a light receiving surface that defines each groove and is closer to the light incident surface. An angle between the light receiving surface and the bottom surface ranges from 35 degrees to 65 degrees. A display apparatus adopting the light guide plate is also provided.

Abstract: A high-voltage light emitting diode (LED) circuit having a plurality of critical voltages and an LED device using the same are described. The high-voltage LED circuit includes a first substrate, at least a first LED formed on the first substrate, and at least an impedance element formed on the first substrate and electrically connected in series with one end of the first LED. The first LED is connected in parallel with at least a second LED based on the characteristics of the impedance element, and the second LED has a polarity opposite to that of the first LED, such that the high-voltage LED circuit may be operated in an AC power supply environment, thereby improving the convenience of using the LEDs.