Abstract: A PWM driving apparatus for an LED includes a sawtooth wave generator (1) for generating a sawtooth wave signal, a comparator (2), an FET (3), a first resistor (4), a second resistor (5), a power supply (7), and a light emitting diodes array (8). A modulation signal provided by a modulation signal source (6) and the sawtooth wave signal 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 the light emitting diodes array.

Abstract: A color projection display device (3) includes a light source (30), a light modulation unit (32), a projection lens (34) and a screen (38). The light modulation unit includes a micro-mirror array (325) having a red micro-mirror, a green micro-mirror and a blue micro-mirror. Each micro-mirror functions as a color filter, and is capable of reflecting light beams emitted from the light source to the projection lens. A driver circuit offers a digital signal to the micro-mirror array to maintain each micro-mirror thereof is in an on state or in an off state. The projection lens projects the light beams reflected by the light modulation unit onto the screen.

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 backlight module (3) includes a light source group (31) and a light guide plate (32). The light source group includes at least a light sources (not labeled), the light guide plate has a light input surface (321) for receiving light and a light output surface (322) for emitting light. The light source group faces the light input surface, which is a curved and its curvature matches with the light distribution of the light source group.

Abstract: A broadband light source (200) includes a pump laser (20), a lanthanide series element-doped fiber (22) having a predetermined length, a WDM device (21) with at least three ports, and first and second optical isolators (23, 28). Two ports (26, 29) of the WDM device respectively connect with the laser and the fiber. The first isolator connects with a third port of the WDM device. The second isolator connects with the fiber. The first and second isolators are located in an output passing of the source for reducing reflection of output light. Pump light is coupled to the fiber by the WDM device, and is amplified by the fiber. A part of the amplified light passes the second isolator and is exported. A remaining part of the amplified light is coupled to the first isolator by the WDM device, and is exported via an output end of the first isolator.