Abstract:
The present invention provides a PWM current adjustment apparatus including a triangle wave generator (8) for generating a triangle wave voltage signal, a comparator (9), an FET (10), a power supply (14), a first resistor (11) and a second resistor (12). The triangle wave voltage signal generated by the triangle wave generator and a modulation signal provided by a modulation voltage source (13) are fed to the comparator, an output of the comparator is connected to a gate terminal of the FET, the power supply is connected to a source terminal of the FET through the first resistor, and a drain terminal of the FET outputs a driving current through the second resistor to a load.
Abstract:
A planar light device (30) for emitting light beams, including a light guide plate (31) having a plurality of diffraction grating units (33). The light guide plate includes a light-emitting surface (313), an opposite bottom surface, and a light incident surface (311) disposed therebetween. A light source (32) is disposed adjacent to the light incident surface. The diffraction grating units cover the bottom surface of the light guide plate. Each diffraction grating unit is divided into a first part (A) and a second part (B), the first and second parts having different alignment directions from each other.
Abstract:
A heat sink (11) includes a base (12), a plurality of fins (14) extending from a first surface of the base, and a plurality of carbon nanotubes (18) formed on an opposite second surface (16) of the base. The carbon nanotubes are substantially parallel to each other and substantially perpendicular to the base. A method for manufacturing the heat sink includes the steps of: (a) providing a heat sink preform comprising a base and a plurality of fins extending from a first surface of the base; (b) polishing an opposite second surface of base; (c) depositing a catalyst film on the second surface of the base; and (d) providing a carbon source gas to grow a plurality of carbon nanotubes on the second surface of the base.
Abstract:
A light guide plate (32) in accordance with the present invention includes a base (23), and an intervening layer (22) formed on the base. The intervening layer includes a light emitting surface (24) defining a plurality of V-shaped grooves (241) thereat. An index of refraction of the intervening layer is less than an index of refraction of the base.
Abstract:
A planar light source device (100) for a display device includes a light guide plate (120) and pluralities of light emitting diodes (110). The light guide plate has a light incident surface (121). The light emitting diodes are located in the vicinity of the light incident surface. Each light emitting diode has a light emission surface opposite to the light incident surface of the light guide plate, and has a diffraction grating (117) provided on the light emission surface for improving a range of divergence of light beams emitted therefrom.
Abstract:
A surface light source unit (3) includes a light source (31) and a light guide plate (30). The light guide plate includes a light incidence surface (301) for receiving light beams, an emission surface (302) for emitting the light beams, and a bottom surface (303) for scattering and diffusing the light beams. A plurality of diffusion dots (311) is formed on the bottom surface and a plurality of protrusions (312) parallel to the light incidence surface is formed on the emission surface with decreasing an interval between two adjacent protrusions as goes away from the light incidence surface. The amount (N) of the protrusions satisfies a condition of N=R/220, wherein R is a distance from the light incidence surface to an opposite surface of the light guide plate. The surface light source unit provides uniform illumination and high brightness for a liquid crystal display panel.