OPTICAL PICK-UP CONTROLLING OPTICAL POWER OF LIGHT SOURCE

摘要

PURPOSE: An optical pick-up controlling optical power of a light source is provided to control the optical power of the light source based on the intensity of a light beam used for recording information on a disc or reproducing the information from the disc so as to maintain the intensity of the light beam optimally. CONSTITUTION: An optical pick-up includes a light source, a photo-detector(28), a beam spot generator(26), an optical means(23), and a controller(29). The photo-detector detects the intensity of an incident beam. The beam spot generator forms a beam spot generating a near field for reading information from a disc using the incident beam. The optical means transmits the beam emitted from the light source to the beam spot generator and delivers the beam from the beam spot generator to the photo-detector. The controller generates a signal of which magnitude corresponds to the intensity of the beam detected by the photo-detector to control the optical power of the light source.