Photodetector and optical pickup apparatus

1. A photodetector comprising:

a first light-receiving surface configured to receive reflected light of zero-order light generated based on a laser beam, from one information recording layer of a multilayer optical disc;

a second light-receiving surface that is adjacent to the first light-receiving surface with a predetermined interval, the second light-receiving surface being configured to receive reflected light of diffracted light generated based on the laser beam, from the one information recording layer; and

a third light-receiving surface for canceling out reflected light of the zero-order light from other information recording layer of the multilayer optical disc, received by the first light-receiving surface or the second light-receiving surface, the third light-receiving surface being configured to receive the reflected light of the zero-order light from other information recording layer, wherein

the third light-receiving surface is disposed on a portion of the second light-receiving surface so as to cancel out the reflected light of the zero-order light from the other information recording layer of the multilayer optical disc, received by the second light-receiving surface.

2. The photodetector of claim 1 , wherein

the reflected light of the diffracted light includes first reflected light of zero-order and diffracted second reflected light that are generated by reflection of the diffracted light on the one information recording layer, and wherein

the third light-receiving surface is disposed on an area other than an area for receiving the second reflected light in the second light-receiving surface when the zero-order light is focused on the one information recording layer.

3. The photodetector of claim 1 , wherein

the reflected light of the diffracted light includes first reflected light of zero-order and diffracted second reflected light that are generated by reflection of the diffracted light on the one information recording layer, and wherein

the third light-receiving surface is disposed on an area other than an area for receiving the first reflected light and the second reflected light in the second light-receiving surface when the zero-order light is focused on the one information recording layer.

4. The photodetector of claim 1 , wherein

the second light-receiving surface includes a first light-receiving area and a second light-receiving area for executing tracking control based on a differential push-pull method, and wherein

the third light-receiving surface is disposed on each of the first light-receiving area and the second light-receiving area.

5. The photodetector of claim 1 , wherein

the diffracted light includes diffracted light of a positive diffraction order and diffracted light of a negative diffraction order generated based on the laser beam, wherein

the second light-receiving surface includes:

a fourth light-receiving surface that is adjacent to the first light-receiving surface with a predetermined interval, the fourth light-receiving surface being configured to receive reflected light of the diffracted light of the positive diffraction order from the one information recording layer; and

a fifth light-receiving surface that is adjacent to the first light-receiving surface with a predetermined interval on the opposite side of the fourth light-receiving surface, the fifth light-receiving surface being configured to receive reflected light of the diffracted light of the negative diffraction order from the one information recording layer, and wherein

the third light-receiving surface includes:

a sixth light-receiving surface disposed on a portion of the fourth light-receiving surface, the sixth light-receiving surface being configured to receive the reflected light of the zero-order light from the other information recording layer, for canceling out the reflected light of the zero-order light from the other information recording layer, received by the fourth light-receiving surface; and

a seventh light-receiving surface disposed on a portion of the fifth light-receiving surface, the seventh light-receiving surface being configured to receive the reflected light of the zero-order light from the other information recording layer, for canceling out the reflected light of the zero-order light from the other information recording layer, received by the fifth light-receiving surface.

6. A photodetector comprising:

a first light-receiving surface configured to receive reflected light of zero-order light generated based on a laser beam, from one information recording layer of a multilayer optical disc;

a second light-receiving surface that is adjacent to the first light-receiving surface with a predetermined interval, the second light-receiving surface being configured to receive reflected light of diffracted light generated based on the laser beam, from the one information recording layer; and

a third light-receiving surface for canceling out reflected light of the zero-order light from other information recording layer of the multilayer optical disc, received by the first light-receiving surface or the second light-receiving surface, the third light-receiving surface being configured to receive the reflected light of the zero-order light from other information recording layer, wherein

the third light-receiving surface is disposed on a portion of the first light-receiving surface so as to cancel out the reflected light of the zero-order light from the other information recording layer of the multilayer optical disc, received by the first light-receiving surface.

7. The photodetector of claim 6 , wherein

the reflected light of the zero-order light includes first reflected light of zero-order and diffracted second reflected light that are generated by reflection of the zero-order light on the one information recording layer, and wherein

the third light-receiving surface is disposed on an area other than an area for receiving the first reflected light and the second reflected light in the first light-receiving surface when the zero-order light is focused on the one information recording layer.

8. An optical pickup apparatus comprising:

a first light-receiving surface configured to receive reflected light of zero-order light generated based on a laser beam, from one information recording layer of a multilayer optical disc;

a second light-receiving surface that is adjacent to the first light-receiving surface with a predetermined interval, the second light-receiving surface being configured to receive reflected light of diffracted light generated based on the laser beam, from the one information recording layer; and

a third light-receiving surface for canceling out reflected light of the zero-order light from other information recording layer of the multilayer optical disc, received by the first light-receiving surface or the second light-receiving surface, the third light-receiving surface being configured to receive the reflected light of the zero-order light from other information recording layer, wherein

the third light-receiving surface is disposed on a portion of the second light-receiving surface so as to cancel out the reflected light of the zero-order light from the other information recording layer of the multilayer optical disc, received by the second light-receiving surface.

9. A photodetector comprising:

a first light-receiving surface configured to receive reflected light of zero-order light generated based on a laser beam, from one information recording layer of a multilayer optical disc; and

a second light-receiving surface that is adjacent to the first light-receiving surface with a predetermined interval, the second light-receiving surface comprising

a first light-receiving area including a light-receiving area configured to receive a portion of first reflected light of zero-order and second reflected light of a positive diffraction order, and

a second light-receiving area including a light-receiving area configured to receive other portion of the first reflected light and third reflected light of a negative diffraction order,

all the reflected lights being generated by reflection of diffracted light generated based on the laser beam, on the one information recording layer,

the first light-receiving area and the second light-receiving area having areas that substantially equalize light amounts of reflected light of the zero-order light from other information recording layer of the multilayer optical disc, received: by the first light-receiving area; and the second light-receiving area.

10. The photodetector of claim 9 , wherein

an area of one light-receiving area, which is a shorter distance from the first light-receiving surface, of the first light-receiving area and the second light-receiving area is set smaller than an area of the other light-receiving area in accordance with a light intensity of the reflected light of the zero-order light from the other information recording layer.

11. The photodetector of claim 9 , wherein

the first light-receiving area and the second light-receiving area

are light-receiving areas formed by dividing a whole light-receiving area of the second light-receiving surface with a first linear dividing line and

receive substantially the same light amounts of the first reflected light when the zero-order light is focused on the one information recording layer, wherein

the first light-receiving area

includes light-receiving areas formed by dividing a whole light-receiving area of the first light-receiving area with a second dividing line orthogonal to the first dividing line and

receives substantially the same light amount of the first reflected light received by the first light-receiving area in each light-receiving area divided with the second dividing line, and wherein

the second light-receiving area

includes light-receiving areas formed by dividing a whole light-receiving area of the second light-receiving area with a third dividing line orthogonal to the first dividing line and

receives substantially the same light amount of the first reflected light received by the second light-receiving area in each light-receiving area divided with the third dividing line.

12. The photodetector of claim 9 , wherein

the diffracted light includes diffracted light of a positive diffraction order and diffracted light of a negative diffraction order generated based on the laser beam, wherein

the second light-receiving surface includes a third light-receiving surface adjacent to the first light-receiving surface with a predetermined interval and a fourth light-receiving surface adjacent to the first light-receiving surface with a predetermined interval on the opposite side of the third light-receiving surface, wherein

the third light-receiving surface includes a third light-receiving area and a fourth light-receiving area, wherein

the fourth light-receiving surface includes a fifth light-receiving area and a sixth light-receiving area, wherein

the third light-receiving area is a light-receiving area, corresponding to the first light-receiving area, including a light-receiving area configured to receive a portion of fourth reflected light of zero-order and fifth reflected light of a positive diffraction order that are generated by reflection of the diffracted light of the positive diffraction order on the one information recording layer, wherein

the fourth light-receiving area is a light-receiving area, corresponding to the second light-receiving area, including a light-receiving area configured to receive other portion of the fourth reflected light and sixth reflected light of a negative diffraction order, wherein

the fifth light-receiving area is a light-receiving area, corresponding to the first light-receiving area, including a light-receiving area configured to receive a portion of seventh reflected light of zero-order and eighth reflected light of a positive diffraction order that are generated by reflection of the diffracted light of the negative diffraction order on the one information recording layer, and wherein

the sixth light-receiving area is a light-receiving area, corresponding to the second light-receiving area, including a light-receiving area configured to receive other portion of the seventh reflected light and ninth reflected light of a negative diffraction order.

13. An optical pickup apparatus comprising the photodetector of claim 9 .