1: An optical module comprising:
a light emitting element;
an optical fiber;
a wavelength separating filter that is arranged at a predetermined angle with respect to a longitudinal direction of the optical fiber on a plane including the longitudinal direction of the optical fiber; and
a lens for focusing light emitted from the light emitting element on the optical fiber via the wavelength separating filter, wherein
the light emitting element is arranged while being offset in a direction perpendicular to a central axis of the lens on a plane where the wavelength separating filter has the predetermined angle with respect to the central axis of the lens.
2: An optical module comprising:
a light emitting element;
an optical fiber;
a wavelength separating filter that is arranged at a predetermined angle with respect to a longitudinal direction of the optical fiber on a plane including the longitudinal direction of the optical fiber;
a lens for focusing light emitted from the light emitting element on the optical fiber via the wavelength separating filter; and
a dielectric medium substrate that is arranged between the lens and the wavelength separating filter such that the dielectric medium substrate has an inclination on a plane having a central axis of the lens among planes perpendicular to a plane where the wavelength separating filter has the predetermined angle.
3: An optical module comprising:
a light emitting element;
an optical fiber;
a wavelength separating filter that is arranged at a predetermined angle with respect to a longitudinal direction of the optical fiber on a plane including the longitudinal direction of the optical fiber;
a lens for focusing light emitted from the light emitting element on the optical fiber via the wavelength separating filter; and
an optical isolator that includes a Faraday rotator as a parallel flat-plate and is arranged between the lens and the wavelength separating filter such that the parallel flat-plate has an inclination on a plane including a central axis of the lens among planes perpendicular to a plane where the wavelength separating filter has the predetermined angle.
4: The optical module according to claim 1, further comprising:
a light receiving element; and
a light-receiving-side lens for focusing light output from the optical fiber on the light receiving element, wherein
the wavelength separating filter is configured to reflect the light output from the optical fiber and to cause the reflected light to be incident on the light-receiving-side lens.
5: The optical module according to claim 2, further comprising:
a light receiving element; and
a light-receiving-side lens for focusing light output from the optical fiber on the light receiving element, wherein
the wavelength separating filter is configured to reflect the light output from the optical fiber and to cause the reflected light to be incident on the light-receiving-side lens.
6. (canceled)
7: The optical module according to claim 1, further comprising an optical isolator that is arranged between the lens and the wavelength separating filter.
8-9. (canceled)
10: The optical module according to claim 7, wherein
a Faraday rotator that constitutes the optical isolator is formed as a parallel flat-plate, and
the parallel flat-plate has an inclination on the plane including the central axis of the lens among the planes perpendicular to the plane where the wavelength separating filter has the predetermined angle.
11. (canceled)
12: The optical module according to claim 4, wherein
the wavelength separating filter is a first wavelength separating filter, the light-receiving-side lens is a first light-receiving-side lens, and the light receiving element is a first light receiving element, and
the optical module further comprises:
a second light receiving element;
a second wavelength separating filter that is arranged between the optical fiber and the first wavelength separating filter and is configured to transmit one part of the light output from the optical fiber to pass through a side of the first wavelength separating filter, to reflect another part of the light output from the optical fiber other than the one part of the light, and to cause the reflected light to be incident on the second light receiving element; and
a second light-receiving-side lens for focusing the light incident on the second light-receiving-side lens from the second wavelength separating filter on the second light receiving element.
13: The optical module according to claim 1, wherein
the wavelength separating filter is a first wavelength separating filter, and
the optical module further comprises:
a light receiving element;
a second wavelength separating filter that is arranged between the optical fiber and the first wavelength separating filter such that the second wavelength separating filter has a predetermined inclination angle with respect to a longitudinal direction of the optical fiber on a plane including the longitudinal direction of the optical fiber and is configured to transmit one part of the light output from the optical fiber to pass through a side of the first wavelength separating filter, to reflect another part of the light output from the optical fiber other and the one part of the light, and to cause the reflected light to be incident on the light receiving element; and
a light-receiving-side lens for focusing the light incident on the light-receiving-side lens from the second wavelength separating filter on the light receiving element.
14: The optical module according to claim 13, further comprising:
a first optical isolator that is arranged between the first transmission-side lens and the first wavelength separating filter;
a second optical isolator that is arranged between the second transmission-side lens and the second wavelength separating filter; and
a lens between filters that is arranged between the first wavelength separating filter and the second wavelength separating filter.
15: The optical module according to claim 1, wherein
the wavelength separating filter is a first wavelength separating filter, and
the optical module further comprises:
a light receiving element;
a second wavelength separating filter that is arranged between the optical fiber and the first wavelength separating filter and is configured to transmit one part of the light output from the optical fiber to pass through a side of the first wavelength separating filter, to reflect another part of the light output from the optical fiber other than the one part of the light, and to cause the reflected light to be incident on the light receiving element;
a light-receiving-side lens for focusing the light incident on the light-receiving-side lens from the second wavelength separating filter on the light receiving element;
a first optical isolator that is arranged between the first transmission-side lens and the first wavelength separating filter;
a second optical isolator that is arranged between the second transmission-side lens and the second wavelength separating filter;
a lens between filters that is arranged between the first wavelength separating filter and the second wavelength separating filter; and
a lens between a filter and an optical fiber that is arranged between the second wavelength separating filter and the optical fiber, and
the lens between filters is configured to collimate the light reflected at the first wavelength separating filter and to cause the collimated light to be incident on the second wavelength separating filter.
16: The optical module according to claim 5, wherein
the wavelength separating filter is a first wavelength separating filter, the light-receiving-side lens is a first light-receiving-side lens, and the light receiving element is a first light receiving element, and
the optical module further comprises:
a second light receiving element;
a second wavelength separating filter that is arranged between the optical fiber and the first wavelength separating filter and is configured to transmit one part of the light output from the optical fiber to pass through a side of the first wavelength separating filter, to reflect another part of the light output from the optical fiber other than the one part of the light, and to cause the reflected light to be incident on the second light receiving element; and
a second light-receiving-side lens for focusing the light incident on the second light-receiving-side lens from the second wavelength separating filter on the second light receiving element.
17: The optical module according to claim 2, wherein
the wavelength separating filter is a first wavelength separating filter, and
the optical module further comprises:
a light receiving element;
a second wavelength separating filter that is arranged between the optical fiber and the first wavelength separating filter such that the second wavelength separating filter has a predetermined inclination angle with respect to a longitudinal direction of the optical fiber on a plane including the longitudinal direction of the optical fiber and is configured to transmit one part of the light output from the optical fiber to pass through a side of the first wavelength separating filter, to reflect another part of the light output from the optical fiber other and the one part of the light, and to cause the reflected light to be incident on the light receiving element; and
a light-receiving-side lens for focusing the light incident on the light-receiving-side lens from the second wavelength separating filter on the light receiving element.
18: The optical module according to claim 17, further comprising:
a first optical isolator that is arranged between the first transmission-side lens and the first wavelength separating filter;
a second optical isolator that is arranged between the second transmission-side lens and the second wavelength separating filter; and
a lens between filters that is arranged between the first wavelength separating filter and the second wavelength separating filter.
19: The optical module according to claim 2, wherein
the wavelength separating filter is a first wavelength separating filter, and
the optical module further comprises:
a light receiving element;
a second wavelength separating filter that is arranged between the optical fiber and the first wavelength separating filter and is configured to transmit one part of the light output from the optical fiber to pass through a side of the first wavelength separating filter, to reflect another part of the light output from the optical fiber other than the one part of the light, and to cause the reflected light to be incident on the light receiving element;
a light-receiving-side lens for focusing the light incident on the light-receiving-side lens from the second wavelength separating filter on the light receiving element;
a first optical isolator that is arranged between the first transmission-side lens and the first wavelength separating filter;
a second optical isolator that is arranged between the second transmission-side lens and the second wavelength separating filter;
a lens between filters that is arranged between the first wavelength separating filter and the second wavelength separating filter; and
a lens between a filter and an optical fiber that is arranged between the second wavelength separating filter and the optical fiber, and
the lens between filters is configured to collimate the light reflected at the first wavelength separating filter and to cause the collimated light to be incident on the second wavelength separating filter.
20: The optical module according to claim 3, further comprising:
a light receiving element; and
a light-receiving-side lens for focusing light output from the optical fiber on the light receiving element, wherein
the wavelength separating filter is configured to reflect the light output from the optical fiber and to cause the reflected light to be incident on the light-receiving-side lens.
21: The optical module according to claim 20, wherein
the wavelength separating filter is a first wavelength separating filter, the light-receiving-side lens is a first light-receiving-side lens, and the light receiving element is a first light receiving element, and
the optical module further comprises:
a second light receiving element;
a second wavelength separating filter that is arranged between the optical fiber and the first wavelength separating filter and is configured to transmit one part of the light output from the optical fiber to pass through a side of the first wavelength separating filter, to reflect another part of the light output from the optical fiber other than the one part of the light, and to cause the reflected light to be incident on the second light receiving element; and
a second light-receiving-side lens for focusing the light incident on the second light-receiving-side lens from the second wavelength separating filter on the second light receiving element.
22: The optical module according to claim 3, wherein
the wavelength separating filter is a first wavelength separating filter, and
the optical module further comprises:
a light receiving element;
a second wavelength separating filter that is arranged between the optical fiber and the first wavelength separating filter such that the second wavelength separating filter has a predetermined inclination angle with respect to a longitudinal direction of the optical fiber on a plane including the longitudinal direction of the optical fiber and is configured to transmit one part of the light output from the optical fiber to pass through a side of the first wavelength separating filter, to reflect another part of the light output from the optical fiber other and the one part of the light, and to cause the reflected light to be incident on the light receiving element; and
a light-receiving-side lens for focusing the light incident on the light-receiving-side lens from the second wavelength separating filter on the light receiving element.
23: The optical module according to claim 22, further comprising:
a first optical isolator that is arranged between the first transmission-side lens and the first wavelength separating filter;
a second optical isolator that is arranged between the second transmission-side lens and the second wavelength separating filter; and
a lens between filters that is arranged between the first wavelength separating filter and the second wavelength separating filter.
24: The optical module according to claim 3, wherein
the wavelength separating filter is a first wavelength separating filter, and
the optical module further comprises:
a light receiving element;
a second wavelength separating filter that is arranged between the optical fiber and the first wavelength separating filter and is configured to transmit one part of the light output from the optical fiber to pass through a side of the first wavelength separating filter, to reflect another part of the light output from the optical fiber other than the one part of the light, and to cause the reflected light to be incident on the light receiving element;
a light-receiving-side lens for focusing the light incident on the light-receiving-side lens from the second wavelength separating filter on the light receiving element;
a first optical isolator that is arranged between the first transmission-side lens and the first wavelength separating filter;
a second optical isolator that is arranged between the second transmission-side lens and the second wavelength separating filter;
a lens between filters that is arranged between the first wavelength separating filter and the second wavelength separating filter; and
a lens between a filter and an optical fiber that is arranged between the second wavelength separating filter and the optical fiber, and
the lens between filters is configured to collimate the light reflected at the first wavelength separating filter and to cause the collimated light to be incident on the second wavelength separating filter.
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. An electromagnetic shield for shielding a magnetic field produced around a one or more coils having ac current flowing in the one or more coils, through which a workpiece moves for induction heating of the workpiece by the magnetic field, the electromagnetic shield comprising:
a first transverse screen element and a second transverse screen element through which the workpiece moves, the first and second transverse screen elements disposed at opposing ends of the one or more coils, each of the first and second transverse screen elements having a discontinuity,
a first longitudinal screen section connecting a first end of the first transverse screen element at the discontinuity in the first transverse screen element to a first end of the second transverse screen element at the discontinuity in the second transverse screen element, the first longitudinal screen section disposed laterally to an edge of the workpiece; and
a second longitudinal screen section connecting a second end of the first transverse screen element at the discontinuity in the first transverse screen element to a second end of the second transverse screen element at the discontinuity in the second transverse screen element, the second longitudinal screen section disposed laterally to the edge of the workpiece and adjacent to the first longitudinal screen section, whereby current induced in the electromagnetic shield by the, magnetic field flows in the closed circuit path established by the first transverse screen element, the first longitudinal screen section, the second transverse screen element and the second longitudinal screen section, and opposing electromagnetic fields established by opposing currents in the first and second longitudinal screen sections substantially cancel each other.
2. The electromagnetic shield of claim 1 wherein the first and second longitudinal screen sections extend around the perimeters of the first transverse screen element and second transverse screen element to form a substantially closed box-shaped electromagnetic screen around the one or more coils.
3. The electromagnetic shield of claim 1 wherein the sides of the first and second transverse screen elements adjacent to the edge of the workpiece opposite the edge of the workpiece adjacent to the first and second longitudinal screen sections are formed from a flexible material to allow bending the electromagnetic shield along the length of the workpiece to permit further opening of the discontinuity between the first and second longitudinal screen sections for removal of the workpiece.
4. The electromagnetic shield of claim 2 wherein the sides of the first and second transverse screen elements adjacent to the edge of the workpiece opposite the edge of the workpiece adjacent to the first and second longitudinal screen sections are formed from a flexible material to allow bending the electromagnetic shield along the length of the workpiece to permit further opening of the discontinuity between the first and second longitudinal screen sections for removal of the workpiece.
5. A method of shielding a magnetic field produced around a one or more coils having an ac current flowing in the one or more coils through which a workpiece moves for induction heating of the workpiece by the magnetic field, the method comprising:
forming a first transverse screen element through which the workpiece moves at a first end of the one or more coils, the first transverse screen element having a discontinuity located adjacent to an edge of the workpiece;
forming a second transverse screen element through which the workpiece moves at the end of the one or more coils opposite the first end, the second transverse screen element having a discontinuity located adjacent to the edge of the workpiece;
connecting a first longitudinal screen section between a first end of the fist transverse screen element at the discontinuity in the first transverse screen element to a first end of the second transverse screen element at the discontinuity in the second transverse screen element, the first longitudinal screen section disposed laterally to an edge of the workpiece; and
connecting a second longitudinal screen section between a second end of the second transverse screen element at the discontinuity in the first transverse screen element to a second end of the second transverse screen element at the discontinuity in the second transverse screen element, the second longitudinal screen section disposed laterally to the edge of the workpiece and adjacent to the first longitudinal screen element.
6. The method of claim 5 further comprising the step of extending the first and second longitudinal screen sections around the perimeters of the first and second transverse screen elements to form a substantially box-shaped electromagnetic shield around the one or more coils.
7. The method of claim 5 further comprising the step of forming the sides of the first and second transverse screen elements adjacent to the edge of the workpiece opposite the edge of the workpiece adjacent to the first and second longitudinal screen section from a flexible material.
8. The method of claim 6 further comprising the step of forming the sides of the first and second transverse screen elements adjacent to the edge of the workpiece opposite the edge of the workpiece adjacent to the first and second longitudinal screen section from a flexible material.
9. An electromagnetic shield for shielding a magnetic field produced around a one or more coils having ac current flowing through the one or more coils, through which a workpiece moves for induction heating of the workpiece by the magnetic field, the electromagnetic shield comprising:
a first transverse screen element through which the workpiece moves, the first transverse screen element disposed at a first end of the one or more coils, the first transverse screen element having a first discontinuity and a second discontinuity, the first and second discontinuities of the first transverse screen element disposed on opposing sides of the workpiece, the first and second discontinuities in the first transverse screen element separating the first transverse screen element into a first and second partial first transverse screen elements;
a second transverse screen element through which the workpiece moves, the second transverse screen element disposed at the end of the one or more coils opposing the first end, the second transverse screen element having a first discontinuity and a second discontinuity, the first and second discontinuities of the second transverse screen element disposed on opposing sides of the workpiece, the first and second discontinuities in the second transverse screen element separating the second transverse screen element into a first and second partial second transverse screen elements;
a first longitudinal screen element connecting a first end of the first transverse screen element at the first discontinuity in the first transverse screen element to a first end of the second transverse screen element at the first discontinuity in the second transverse screen element, the first longitudinal screen element disposed laterally to the workpiece;
a second longitudinal screen element connecting a second end of the first transverse screen element at the first discontinuity in the first transverse screen element to a second end of the second transverse screen element at the first discontinuity in the second screen element, the second longitudinal screen element disposed laterally to the workpiece and adjacent to the first longitudinal screen element;
a third longitudinal screen element connecting a first end of the first transverse screen element at the second discontinuity in the first transverse screen element to a first end of the second transverse screen element at the second discontinuity in the second screen element, the third longitudinal screen element disposed laterally to the workpiece; and
a fourth longitudinal screen element connecting a second end of the first transverse screen element at the second discontinuity in the first transverse screen element to a second end of the second transverse screen element at the second discontinuity in the second transverse screen element, the fourth longitudinal screen element disposed laterally to the workpiece and adjacent to the first longitudinal screen element, whereby instantaneous ac current induced in the electromagnetic shield by the magnetic field flows in opposing directions in a first closed circuit path and a second closed circuit path, the first closed circuit path established by a first half screen element comprising the first partial first transverse screen element, the first longitudinal screen section, the first partial second transverse screen element and the third longitudinal screen the second closed circuit path established by a second half screen element comprising the second partial first transverse screen element, the second longitudinal screen section, the second partial second transverse screen element and the fourth longitudinal screen section.
10. The electromagnetic shield of claim 9 wherein the first and third longitudinal screen sections extend around the first partial first transverse screen element and first partial second transverse screen element, and the second and fourth longitudinal screen sections extend around the second partial first transverse screen element and second partial second transverse screen element to form a substantially closed box-shaped electromagnetic screen around the one or more coils.
11. The electromagnetic shield of claim 9 further comprising a means for hinging the first partial first and second transverse screen elements, or the second partial first and second transverse screen elements, along the length of the workpiece to permit pivoting the first or second half screens away from the workpiece for removal of the workpiece from between the first and second half screens.
12. The electromagnetic shield of claim 10 further comprising a means for hinging the first partial first and second transverse screen elements, or the second partial first and second transverse screen elements, along the length of the workpiece to permit pivoting the first or second half screens away from the workpiece for removal of the workpiece from between the first and second half screens.
13. A method of shielding a magnetic field produced around a one or more coils having an ac current flowing through the one or more coils through which a workpiece moves for induction heating of the workpiece by the magnetic field, the method comprising:
forming a first transverse screen element through with the workpiece moves at a first end of the one or more coils, the first transverse screen element having a first discontinuity and a second discontinuity, the first and second discontinuities disposed at the opposing edges of the workpiece located along a lateral edge of the workpiece, the first and second discontinuities in the first transverse screen element separating the first transverse screen element into a first and second partial first transverse screen elements;
forming a second transverse screen element through which the workpiece moves at the end of the one or more coils opposing the first end, the second transverse screen element disposed substantially transverse to the direction in which the workpiece moves, the first and second discontinuities disposed at the opposing edges of the workpiece located along a lateral edge of the workpiece, the first and second discontinuities in the second transverse screen element separating the second transverse screen element into a first and second partial second transverse screen elements;
connecting a first longitudinal screen element between a first end of the first transverse screen element at the first discontinuity in the first screen element to a first end of the second transverse screen element at the first discontinuity in the second screen, the first longitudinal screen element disposed laterally to an edge of the workpiece; and
connecting a second longitudinal screen element between a second end of the first transverse screen element at the first discontinuity in the first screen element to a second end of the second transverse screen element at the first discontinuity in the second transverse screen, the second longitudinal screen element disposed laterally to the edge of the workpiece and adjacent to the first longitudinal screen element;
connecting a third longitudinal screen element between a first end of the first transverse screen element at the second discontinuity in the first screen element to a first end of the second transverse screen element at the second discontinuity in the second screen, the third longitudinal screen element disposed laterally to an edge of the workpiece; and
connecting a fourth longitudinal screen element between a second end of the first transverse screen element at the second discontinuity in the first screen element to a second end of the second transverse screen element at the second discontinuity in the second transverse screen, the fourth longitudinal screen element disposed laterally to the edge of the workpiece and adjacent to the third longitudinal screen element.
14. The method of claim 13 further comprising the step of extending the first and third longitudinal screen sections around the perimeters of the first partial first and second transverse screen elements, and the second and fourth longitudinal screen sections around the perimeters of the second partial first and second transverse screen elements to form a substantially box-shaped electromagnetic shield around the one or more coils.