Abstract: The present invention relates to an LED array driving apparatus and a backlight driving apparatus using the same which enables regulation of analogue and PWM dimming for each channel and LED of a backlight, thereby allowing uniform luminance and color in all regions of backlight. The invention converts power with a constant voltage regulator to provide PWM pulse type power to the LED array having a plurality of LEDs connected in series. It regulates the on/off interval of the constant voltage regulator via a PWM dimmer to adjust the duty ratio of the PWM pulse. Further, it regulates the level of the driving current detected at the LED array via the feedback controller and analogue dimmer to apply to the constant voltage regulator by feedback process, thus regulating the amplitude of the PWM pulse.

Abstract: Disclosed is an optical pickup device, which comprises a twin LD (Laser Diode) and an achromatic prism for compensating for optical axes, thereby omitting a separate optical component such as an HOE (Holographic Optical Element) or a wedge beam splitter and having a simple optical pickup structure. The optical pickup device includes a light emitting element for emitting two or more light beams having different wavelengths; an objective lens for converging the light beams emitted from the light emitting element onto an optical disk; a light receiving element for receiving light beams reflected by the optical disk; a beam splitter installed at an optical route between the light emitting element and the objective lens; and an achromatic prism installed at an optical route between the light emitting element and the beam splitter.