1. An electronic apparatus comprising:
a casing which includes a first casing portion having a first thickness and a second casing portion having a second thickness;
a fan case which are provided in the first casing portion and the second casing portion, and which includes a first fan case portion having a first extent and a second fan case portion having a second extent; and
a fan which includes a first blade portion having a first size and a second blade portion having a second size so that at least a part of the second blade portion is provided in the second fan case portion.
2. The apparatus of claim 1, wherein the fan case is provided to surround at least a part of the fan.
3. The apparatus of claim 1, wherein the second thickness of the casing is smaller than the first thickness thereof.
4. The apparatus of claim 1, wherein the fan case is provided inside each of the first casing portion and the second casing portion.
5. The apparatus of claim 1, wherein the second extent of the fan case is narrower than the first extent thereof.
6. The apparatus of claim 1, wherein the second size of the fan is smaller than the first size thereof.
7. The apparatus of claim 1, wherein the second casing portion is provided in at least a part of a peripheral portion of the electronic apparatus.
8. The apparatus of claim 1, wherein a part of the second fan case is provided in the second casing portion, and wherein the second blade portion is provided in a part of the second fan case.
9. An electronic apparatus comprising:
a casing which includes a first casing portion having a first thickness and a second casing portion having a second thickness;
which are provided in the first casing portion and the second casing portion, and which includes a first fan case portion having a first extent and a second fan case portion having a second extent; and
a fan which includes a blade portion so that at least a part of the blade portion is provided in the second fan case portion.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
What is claimed is:
1. An optical current transducer configured to sense current in a conductor, comprising:
a light source;
a polarizer configured to generate linearly polarized light received from the light source;
a magneto-optic garnet comprising Bismuth (Bi), Iron (Fe), and Oxygen (O), configured to be coupled to the conductor and in optical communication with the polarizer, the magneto-optic garnet configured to rotate the polarization of the linearly polarized light received from the polarizer; and
an analyzer in optical communication with the magneto-optic garnet, the analyzer configured to detect the rotation of the linearly polarized light caused by the magneto-optic garnet.
2. The optical current transducer of claim 1, wherein the magneto-optic garnet includes a gadolinium (Gd) gallium (Ga) garnet (GGG) substrate.
3. The optical current transducer of claim 1, wherein the magneto-optic garnet further comprises an element selected from the group consisting of Yttrium (Y) and Lutetium (Lu).
4. The optical current transducer of claim 1, wherein the magneto-optic garnet further comprises an element selected from the group consisting essentially of Yttrium (Y) and Lutetium (Lu), to provide a magneto-optic garnet having a Verdet Constant in the range of at least 80 degcmG.
5. The optical current transducer of claim 1, wherein the magneto-optic garnet further comprises a substrate.
6. The optical current transducer of claim 5, wherein the magneto-optic garnet is a thin-film disposed on the substrate.
7. The optical sensor of claim 1, wherein the magneto-optic garnet has a chemical composition that may be represented as (BixLu1-x)3Fe5O12.
8. The optical sensor of claim 1, wherein the magneto-optic garnet has a chemical composition that may be represented as (BixY1-x)3Fe5O12.
9. The optical sensor of claim 1, further comprising a lens for communicating light between the magneto-optic garnet and the light source.
10. The optical sensor of claim 1, further comprising an input optical cable transmitting light from the light source to the polarizer.
11. The optical sensor of claim 10, further comprising an output optical cable transmitting light from the analyzer to at least one beam splitter.
12. The optical sensor claim 11, wherein the optical cable comprises multi-mode optical fiber.
13. The optical sensor of claim 2, wherein the light source provides at least two distinct wavelengths of light.
14. The optical sensor of claim 13, wherein the light source comprises at least two LEDs.
15. The optical sensor of claim 13, wherein the light source comprises a halogen lamp.
16. The optical sensor of claim 1, further comprising:
at least one photodetector, receiving light from the analyzer.
17. The optical sensor of claim 16, further comprising:
a data collection apparatus, receiving an electrical signal from the at least one photodetector.
18. The optical sensor of claim 1, wherein the magneto-optic garnet rotates the direction of polarization by an angle substantially represented by the relationship V(,T)Hd, where V is the temperature and wavelength dependent Verdet Constant, H is the component of the magnetic field that is perpendicular to the plane of the magneto-optic garnet, and d is the thickness of the active material.
19. A method of measuring current in a conductor, comprising:
providing a light source;
communicating light from the light source to a polarizer configured to generate linearly polarized light;
communicating the linearly polarized light from the polarizer to a magneto-optic garnet comprising Bismuth (Bi), Iron (Fe), and Oxygen (O), the magneto-optic garnet configured adjacent the conductor so that the magnetic field vector, caused by the conductor current, is perpendicular to the garnet film surface, the magneto-optic garnet configured to rotate the polarization of the linearly polarized light received from the polarizer; and
communicating the rotated light from the magneto-optic garnet to an analyzer in optical communication with the magneto-optic garnet, the analyzer configured to detect the rotation of the linearly polarized light caused by the magneto-optic garnet.
20. The method of claim 19, further comprising:
providing light from the analyzer to a first beam splitter.
21. The method of claim 20, further comprising:
providing at least some of the light from the first beam splitter to a second beam splitter.
22. The method of claim 21, further comprising;
receiving, by a detector a first light component from the first beam splitter and a second light component from the second beam splitter.
23. An optical current transducer configured to sense current in a conductor, comprising:
a light source; and
a sensor head, the sensor head including,
a polarizer configured to generate linearly polarized light received from the light source;
a magneto-optic garnet comprising Bismuth (Bi), Iron (Fe), and Oxygen (O), configured to be coupled to the conductor and in optical communication with the polarizer, the magneto-optic garnet configured to rotate the polarization of the linearly polarized light received from the polarizer; and
an analyzer in optical communication with the magneto-optic garnet, the analyzer configured to detect the rotation of the linearly polarized light caused by the magneto-optic garnet.
24. The optical current transducer of claim 23, wherein the sensor head is attached to the conductor.
25. The optical current transducer of claim 24, wherein the sensor head is attached to the conductor at a location on the conductor where the cross section of the conductor has the substantially smallest overall radius of curvature.
26. The optical current transducer of claim 24, wherein the magneto-optic garnet is a thin-film having a film-plane and the film-plane is substantially oriented parallel to the direction of current flow through the conductor.
27. The optical current transducer of claim 24, wherein the magneto-optic garnet has a crystallographic direction and the polarizer polarizes light substantially parallel to the crystallographic direction.
28. A method of temperature compensation, for a current sensor, comprising:
providing a light source including more than one wavelength to a sensor head;
measuring the light intensity of more than one wavelength 6 of light;
determining the temperature of the current sensor based on at least one ratio of light intensity of one wavelength of light to another wavelength of light;
determining a Verdet Constant based on the temperature;
determining light intensity based on the temperature and the Verdet Constant; and
determining the current detected by the current sensor based on the temperature and Verdet Constant.
29. A method of determining the temperature of a current sensor, comprising:
providing a light source having a first wavelength and a second wavelength;
providing a current sensor head for receiving light from the light source;
detecting light intensity at the first wavelength and at the second wavelength from the current sensor head; and
determining temperature of the sensor head based on a ratio of light intensity in the first wavelength to light intensity of the second wavelength.
30. A method of sensor drift for a current sensor, comprising:
providing a light source having a first wavelength, a second wavelength, and third wavelength;
providing a current sensor head for receiving light from the light source;
detecting light intensity at the first wavelength, at the second wavelength, and at the third wavelength, the light coming from the sensor head
determining a first intensity ratio of the first intensity and the third intensity, and a second intensity ratio of the second intensity and the third intensity; and
determining sensor drift over time based on the first intensity ratio and the second intensity ratio.