Optical pickup and optical disc device

Abstract

An optical pickup according to the present invention includes an integrated circuit element (LDD) 5 for driving first, second, and third semiconductor lasers 3, 4 , and 5 . The LDD 50 is shaped so as to have a rectangular principal face surrounded by one side, with a plurality of input/output pins being arranged along each side. The plurality of input/output pins include a first pin group connected to a blue-violet laser 5 whose oscillation wavelength is the shortest, a second pin group connected to a red laser 4 , and a third pin group connected to an infrared laser 3 . The wiring structure of the optical pickup includes a first transmission line 41 for connecting the first pin group to the blue-violet laser 5 , a second transmission line 33 for connecting the second pin group to the red laser 4 , and a third transmission line 31 for connecting the third pin group to the infrared laser 3 , where the first transmission line 41 is shorter than both the second and third transmission lines 31 and 33 . Of the rectangular principal face of the LDD 50 , the side along which the first pin group is provided is orthogonal to the side along which the second pin group is provided or to the side along which the third pin group is provided.

1 . An optical pickup for performing data recording or reproduction by using a plurality of light beams of different wavelengths, comprising:
 a first semiconductor laser for emitting a first light beam having a first wavelength;   a second semiconductor laser for emitting a second light beam having a second wavelength which is longer than the first wavelength;   at least one objective lens for converging the first and second light beams;   an integrated circuit element for driving the first and second semiconductor lasers based on an external signal, the integrated circuit element being shaped so as to have a rectangular principal face surrounded by four sides, with a plurality of input/output pins being arranged along each side, the plurality of input/output pins including a first pin group connected to the first semiconductor laser and a second pin group connected to the second semiconductor laser; and   a wiring structure including a first transmission line for connecting the first pin group of the integrated circuit element to the first semiconductor laser and a second transmission line for connecting the second pin group to the second semiconductor laser, wherein,   the first transmission line is shorter than the second transmission line.   
   
   
       2 . The optical pickup of  claim 1 , wherein, of the rectangular principal face of the integrated circuit element, the side along which the first pin group is provided is orthogonal to the side along which the second pin group is provided. 
   
   
       3 . The optical pickup of  claim 1 , further comprising light detection means for generating an electrical signal in response to at least a portion of the first and second light beams reflected from an optical disk. 
   
   
       4 . The optical pickup of  claim 2 , further comprising light detection means for generating an electrical signal in response to at least a portion of the first and second light beams reflected from an optical disk. 
   
   
       5 . An optical pickup for performing data recording and reproduction by using a plurality of light beams of different wavelengths, comprising:
 a first semiconductor laser for emitting a first light beam having a first wavelength;   a second semiconductor laser for emitting a second light beam having a second wavelength which is longer than the first wavelength;   at least one objective lens for converging the first and second light beams;   an integrated circuit element for driving the first and second semiconductor lasers based on an external signal, the integrated circuit element being shaped so as to have a rectangular principal face surrounded by four sides, with a plurality of input/output pins being arranged along each side, the plurality of input/output pins including a first pin group connected to the first semiconductor laser and a second pin group connected to the second semiconductor laser;   a wiring structure including a first transmission line for connecting the first pin group of the integrated circuit element to the first semiconductor laser and a second transmission line for connecting the second pin group to the second semiconductor laser; and   light detection means for generating an electrical signal in response to at least a portion of the first and second light beams reflected from an optical disk, wherein,   of the rectangular principal face of the integrated circuit element, the side along which the first pin group is provided is orthogonal to the side along which the second pin group is provided, and the first transmission line is shorter than the second transmission line.