Optical pickup and optical storage device

Abstract

An optical pickup for an optical storage device includes a stem, a substrate mounted on the stem, and a laser diode mounted on the substrate. The substrate is integrally formed with an optical signal detector and an error signal detector for focusing error detection and tracking error detection. A cap is mounted on the stem so as to accommodate the substrate and the laser diode. A beam splitter unit including a polarization beam splitter and a beam splitting element is mounted on the cap. A hologram for diffracting a reflected beam toward the error signal detector is interposed between the cap and the beam splitter unit. The substrate is biased at a given potential, and has an insulating film opposed to the stem.

1 - 24 . (canceled)  
   
   
       25 . An optical pickup comprising: 
 a stem;    a substrate mounted on said stem;    a laser diode for outputting a laser beam;    a photodetector provided on said substrate for detecting return light from an object to be irradiated with said laser beam; and    a metal layer provided on said substrate so as to cover at least a region adjacent to said photodetector, said metal layer having a surface modified so as to have light absorptivity.    
   
   
       26 . An optical pickup according to  claim 25 , wherein said metal layer comprises an anodized aluminum film.  
   
   
       27 . An optical storage device capable of at least reading information stored in an optical storage medium, comprising: 
 a base;    a carriage movable along said optical storage medium;    a stem mounted on said base;    a substrate mounted on said stem;    a laser diode for outputting a laser beam;    an objective lens mounted on said carriage for focusing said laser beam from said laser diode onto said optical storage medium;    a photodetector provided on said substrate for detecting at least a regenerative signal from a reflected beam from said optical storage medium; and    a metal layer provided on said substrate so as to cover at least a region adjacent to said photodetector, said metal layer having a surface modified so as to have light absorptivity.    
   
   
       28 . An optical storage device according to  claim 27 , wherein said metal layer comprises an anodized aluminum film.