Optical pickup device having a wavelength selecting film and an optical reflector

Abstract

An optical pickup device has first and second light sources that emit first and second laser beams of different wavelengths, an object lens that concentrates the first and second laser beams on a data recording surface of an optical disk, an optical separator disposed between the first and second light sources and the object lens, and an optical monitor that detects a quantity of light of the second laser beam. The optical separator has a wavelength selecting film that, on one hand, reflects the first laser beam emitted from the first light source toward the object lens and, on the other hand, transmits the second laser beam emitted from the second light source to the object lens, and a reflector that reflects a part of the second laser beam emitted from the second light source toward the optical monitor.

1 . An optical pickup device comprising: 
 a first light source that emits a first laser beam of a wavelength;    a second light source that emits a second laser beam of a wavelength different from the wavelength of the first laser beam;    an object lens that concentrates the first and second laser beams on a data recording surface of an optical disk;    an optical monitor that detects a quantity of light of the second laser beam; and    an optical separator comprising; 
 a wavelength selecting film that, 
 reflects the first laser beam emitted from the first light source toward the object lens, and  
 transmits the second laser beam emitted from the second light source to the object lens, and  
 
 a reflector that reflects a part of the second laser beam emitted from the second light source toward the optical monitor, wherein said part of the second laser beam is not incident on the wavelength selecting film, and  
 wherein the reflector and the wavelength selecting film are in contact.  
   
   
   
       2 . The optical pickup device as claimed in  claim 1 , wherein the reflector is arranged in the vicinity of the wavelength selecting film.  
   
   
       3 . The optical pickup device as claimed in  claim 1 , wherein the reflector is a reflection mirror.  
   
   
       4 . The optical pickup device as claimed in  claim 1 , wherein the reflector is a half-reflection film which is laid on the wavelength selecting film.