1. An optical head comprising:
a first light emitting unit configured to emit a first light beam having a first wavelength and a first optical axis;
a second light emitting unit configured to emit a second light beam having a second wavelength greater than the first wavelength and a second optical axis;
a polarizing unit configured to polarize the first and second light beams respectively emitted from the first and second light emitting units, and reflects a first reflected light and a second reflected light which are obtained when the first and second light beams are reflected from an optical disk, respectively;
a converging unit configured to converge the first and second light beams transmitted through the polarizing unit on the optical disk;
a detecting unit configured to detect the first and second reflected lights reflected from the polarizing unit; and
a diffracting unit provided on optical paths of the first and second reflected lights, which are located between the polarizing unit and the converging unit, the diffracting unit being configured to diffract the first and second reflected lights,
wherein the first and second light emitting units are provided such that when the first and second light beams are incident on the converging unit, one of the first and second optical axes of the first and second light beams diverges from the other by a predetermined angle.
2. The optical head according to claim 1, wherein the detecting means includes an area for focusing, which receives a first reflected light component of the first and second reflected lights diffracted by the diffracting unit, and generates a signal for focusing, and an area for tracking, which receives a second reflected light component of the first and second reflected lights diffracted by the diffracting unit, and generates a signal for tracking.
3. The optical head according to claim 2, wherein:
the diffracting unit is circular, and includes a first diffraction area and a second diffraction area;
where the diffracting unit is defined as a reference circle, the first diffraction area is located within half of an area of the reference circle, and includes a diffraction grating having bars arranged at a first pitch, and the second diffraction area is located opposite to the first diffraction area with respect to a extension line including a center of the reference circle, has substantially the same size as the first diffraction area, and includes a diffraction grating having bars arranged at a second pitch differing from the first pitch; and
the area for focusing receives a reflected light component of the first and second reflected lights diffracted by the first and second diffraction areas.
4. The optical head according to claim 3, wherein two circles, which overlap the reference circle, and have centers on a line including a diameter of the reference circle, are defined as a first circle and a second circle,
one of two areas of the reference circle which are divided by the line including the diameter of the reference circle, and are other than overlapping areas of the reference circle and the first and second circles, contains the first diffraction area, and the other of the two areas contains the second diffraction area.
5. The optical head according to claim 3, wherein the first and second diffraction areas are spaced from each other, and a diffraction grating configured to guide the first and second reflected lights to the area for tracking is formed in an area which is other than the first and second diffraction areas.
6. The optical head according to claim 3, which further comprises:
a first diffraction element provided between the first light emitting unit and the polarizing unit, and configured to generate a first main beam and first and second sub beams, all having the first wavelength; and
a second diffraction element provided between the second light emitting unit and the polarizing unit, and configured to generate a second main beam and third and fourth sub beams, all having the second wavelength,
wherein the area for tracking includes a sub-beam receiving area which receives reflected light components of the first to fourth sub beams which are reflected from the optical disk and are diffracted by diffraction areas of the diffracting unit which are other than the first and second diffraction areas.
7. An optical disk drive comprises:
a first light emitting unit configured to emit a first light beam having a first wavelength and a first optical axis;
a second light emitting unit configured to emit a second light beam having a second wavelength greater than the first wavelength and a second optical axis;
a polarizing unit configured to polarize the first and second light beams respectively emitted from the first and second light emitting units, and reflects a first reflected light and a second reflected light which are obtained when the first and second light beams are reflected from an optical disk, respectively;
a converging unit configured to converge the first and second light beams transmitted through the polarizing unit on the optical disk, wherein the first and second light emitting units are provided such that when the first and second light beams are incident on the converting unit, one of the first and second optical axes of the first and second light beams diverges from the other by a predetermined angle;
a detecting unit configured to detect the first and second reflected lights reflected from the polarizing unit;
a diffracting unit provided on optical paths of the first and second reflected lights, which are located between the polarizing unit and the converging unit, the diffracting unit being configured to diffract the first and second reflected lights, and
a controlling unit configured to control tracking and focusing based on a component of one of the first and second reflected lights reflected from the polarizing unit, which are detected by the detecting unit.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. Machine for washing items of various kind comprising:
a stationary washing tub (1) intended to contain the washing liquor,
a fuel cell (2) that receives a stream of gaseous hydrogen and converts said stream into a source of electric power,
means for generating said stream of gaseous hydrogen and transferring said stream to said fuel cell (2),
an electric connector that transfers the electric power generated in said fuel cell to a control and actuation device comprised in said washing machine,
wherein said means for generating said stream of gaseous hydrogen comprises:
a sealed reactor (3), in the interior of which there is placed a mass of metal substances,
a water source,
a first conduit (5) to convey water from said water source to said sealed reactor,
a second conduit (6) to convey a flow of gaseous hydrogen from said sealed reactor to said fuel cell,
a third conduit (7) to convey the water from said sealed reactor (3) to said washing tub, said sealed reactor (3) comprising a first heat exchanger (8) that transfers
heat generated inside said sealed reactor to a heating liquid circulating in said third conduit (7), wherein said third conduit (7) connects an interior volume of said reactor (3) with said tub (1) of the washing machine containing the washing liquor, and in said third conduit (7) said heating liquid circulates in a closed-loop pattern.
2. Washing machine according to claim 1, wherein said metal substances comprise magnesium.
3. Washing machine according claim 2, wherein said water source comprises a reservoir (4), and that said first conduit (5) comprises a first pump (15) and a first valve (16).
4. Machine according to claim 2, wherein said second conduit (6) comprises a second valve (17).
5. Machine according to claim 4, wherein a humidity condenser (10) is arranged in said second conduit (6) downstream of said second valve (17).
6. Machine according to claim 5, wherein in said second conduit (6), downstream of said humidity condenser (10), there is arranged a third valve.
7. Machine according to claim 6, wherein said third valve (11) is a three-way valve, and a third way of said three-way valve leads to a sealed reservoir (18) for containing and storing the excess gaseous hydrogen flowing in form said humidity condenser (10).
8. Machine according to claim 2, wherein said magnesium is associated to a quantity of nickel.
9. Machine according to claim 8, wherein said nickel is associated to said magnesium to a percentage that is not higher than 3% by mass.
10. Machine according to claim 1,
wherein a second pump (27) is installed in said third conduit.
11. Machine according to claim 1, further comprising a second heat exchanger (9) that transfers the heat from said heating liquid flowing through said third conduit to said washing liquor.
12. Machine according to claim 1, wherein said sealed reactor (3) comprises an outer body (38) and an inner body (39), which define a first sealed annular hollow jacket (40) therebetween, which is connected with the outside via two distinct apertures (41, 42), two respective ends of said third conduit (7) being coupled thereto.
13. Machine according to claim 12, further comprising an inner channel (43) arranged within said inner cylindrical body (39), said cylindrical body (39) being coupled at the opposite ends thereof to said first conduit (5) and said second conduit (6), respectively, said inner channel (43) being provided with a plurality of through-holes or perforations (44) opening into said annular hollow jacket.
14. Machine according to claim 13, wherein between said inner cylindrical body (39) and said inner channel (43) there is provided a second annular hollow jacket, in which there is removably received a cartridge (45).
15. Machine according to claim 14, characterized in that said cartridge (45) contains a mass of magnesium formed of minute fragments, flakes or powder.
16. Machine according to claim 1, wherein said reactor (3) comprises at least a temperature sensor (20) andor a pressure sensor (21).