1. A method comprising:
changing a bias current provided to a laser device by discrete current increments;
measuring changes in an output power of a light signal from the laser device in response to the changes in the bias current;
estimating a slope efficiency associated with the laser device based upon at least one of the discrete incremental changes in the bias current and at least one change in the output power; and
determining a magnitude of a modulation current provided to the laser device based upon the estimated slope efficiency and a target output power swing.
2. The method of claim 1, the method further comprises changing the bias current until the output power is within a set or predetermined power range.
3. The method of claim 1, the method further comprising changing the bias current based upon the magnitude of the modulation current to maintain an average of the output power within the set or predetermined range.
4. A laser driver circuit comprising:
an output power monitoring circuit to determine an output power of a light signal from a laser device;
a bias current generating circuit to change a bias current provided to a laser device in discrete current increments;
a circuit to estimate a slope efficiency associated with the laser device based upon at least on of the discrete incremental changes in the bias current and at least one change in the output power; and
a modulation current generating circuit to determine a magnitude of a modulation current provided to the laser device based upon the estimated slope efficiency and a target output power swing.
5. The laser driver circuit of claim 4, wherein the bias current generating circuit changes the bias current until the output power is within a set or predetermined power range.
6. The laser driver circuit of claim 4, wherein the bias current generating circuit comprises logic to change the bias current based upon the magnitude of the modulation current to maintain an average of the output power within the set or predetermined range.
7. A system comprising:
a serializer to provide a serial data signal in response to a parallel data signal;
a laser device adapted to be coupled to an optical transmission medium to transmit an optical signal in the optical transmission medium in response to the serial data signal; and
a laser driver circuit to provide a power signal to the laser device, the laser driver circuit comprising:
an output power monitoring circuit to measure an output power of a light signal from the laser device;
a bias current generating circuit to change a bias current to the laser device in discrete current increments;
a circuit to estimate a slope efficiency associated with the laser device based upon at least one of the discrete incremental changes in the bias current and at least one change in the output power; and
a modulation current generating circuit to determine a magnitude of a modulation current provided to the laser device based upon the estimated slope efficiency and a target output power swing.
8. The system of claim 7, the system further comprising a SONET framer to provide the parallel data signal.
9. The system of claim 8, wherein the system further comprises a switch fabric coupled to the SONET framer.
10. The system of claim 7, the system further comprising an Ethernet MAC to provide the parallel data signal at a media independent interface.
11. The system of claim 10, wherein the system further comprises a multiplexed data bus coupled to the Ethernet MAC.
12. The system of claim 10, wherein the system further comprises a switch fabric coupled to the Ethernet MAC.
13. A system comprising:
a serializer to provide a serial data signal in response to a parallel data signal;
a laser device adapted to be coupled to an optical transmission medium to transmit an optical signal in the optical transmission medium in response to the serial data signal; and
a laser driver circuit to provide a power signal to the laser device, the laser driver circuit comprising:
a first current source circuit to generate a bias current;
a second current source circuit to generate a modulation current; and
a control circuit coupled to the second current source to control a magnitude of the modulation current based upon one or more changes in a magnitude of the bias current and one or more changes in an output power of a light signal transmitted by the laser device;
wherein the control circuit further comprises:
logic to adjust the magnitude of the modulation current to maintain a swing power of the laser device at about a predetermined target modulation power.
14. The system of claim 13, the system further comprising a SONET framer to provide the parallel data signal.
15. The system of claim 14, wherein the system further comprises a switch fabric coupled to the SONET framer.
16. The system of claim 13, the system further comprising an Ethernet MAC to provide the parallel data signal at a media independent interface.
17. The system of claim 16, wherein the system further comprises a multiplexed data bus coupled to the Ethernet MAC.
18. The system of claim 16, wherein the system further comprises a switch fabric coupled to the Ethernet MAC.
19. The system of claim 13, wherein the control circuit comprises logic coupled to the first current source to change the magnitude of the bias current to maintain the average output power of the light signal within a predetermined range.
20. The system of claim 19, wherein the control circuit further comprises:
logic to reduce the bias current based to maintain an average output power of the light signal at about a predetermined target average output power based upon the adjusted magnitude of the modulation current.
21. The system of claim 13, the laser driver circuit further comprising:
a modulation circuit to generate a modulated current signal in response to the modulation current and a data signal; and
a circuit to combine the bias current and the modulated current signal to provide a current signal to the laser device.
22. The system of claim 13, wherein the control circuit further comprises:
an analog to digital conversion circuit to sample a voltage representative of the output power of the laser device; and
a first signal output to provide a first digital control signal to the first current source circuit; and
a second signal output to provide a second digital control signal to the second current source circuit.
23. The system of claim 13, wherein the bias current generating circuit changes the bias current until the output power is within a set of predetermined power range.
24. The system of claim 23, wherein the laser driver circuit comprises a modulation current generating circuit to determine a magnitude of a modulation current provided to the laser device based upon the estimated slope efficiency and a target output power swing.
25. The system of claim 24, wherein the bias current generating circuit comprises logic to change the bias current based upon the magnitude of the modulation current to maintain an average of the output power within the set or predetermined range.
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. A medical X-ray tube system comprising:
an X-ray emission module emitting X-rays using a chipped nano-structured material,
wherein the X-ray emission module is separable from a body.
2. The system of claim 1, wherein the X-ray emission module is rotatable via a rotation axis formed on the body.
3. The system of claim 1, wherein:
the medical X-ray tube system is manufactured in the form of a pen or a pencil, and
the X-ray emission module approaches an inner or outer local portion of human body including inside and outside of the oral cavity to thereby emit X-rays to the approached local portion, and the X-ray emission module is used for diagnoses and cancer therapy including a dental diagnosis and an oral cancer therapy.
4. The system of claim 1, wherein the medical X-ray tube system is used as a brachytherapy apparatus that irradiates X-rays to only a cancer cell excluding a normal tissue.
5. The system of claim 1, wherein the nano-structured material comprises carbon nanotube, carbon nanofiber (CNF), nanowire, graphene, or nanodiamond.
6. The system of claim 1, wherein:
the X-ray emission module comprises an electron emission module comprising a grid portion and a cathode fixed by a fixing unit, and
an electron beam from the cathode is extracted from the grid portion in a vacuum state.
7. The system of claim 1, wherein a vacuum state is maintained by connecting a pipe in the type of a cable to a vacuum line combined with a hole formed in the X-ray emission module and inhaling the inside air of the X-ray emission module via the pipe.
8. The system of claim 1, wherein the X-ray emission module comprises:
an electron emission module based on the nano-structured material;
a focusing lens focusing an electron beam coming from the electron emission module; and
an anode portion emitting X-rays by the electron beam from the focusing lens.
9. The system of claim 8, wherein the anode portion includes a transmission-type target form of applying tungsten or molybdenum to a beryllium (Be) window.
10. The system of claim 1, wherein:
a power supply and vacuum state of the medical X-ray tube system is controlled by a computer system, and
the X-rays emitted from the X-ray emission module and transmitting a diagnostic target are detected by a detector to thereby display a corresponding image on a display unit interworking with the computer system.
11. A diagnostic method of a medical X-ray tube system, the method comprising:
emitting X-rays using a chipped nano-structured material to project the emitted X-rays toward a diagnostic target; and
detecting, using a detector, the X-rays transmitting the diagnostic target to display a corresponding image,
wherein the X-ray tube system of which an X-ray emission module is separable from a body is used in order to replace a cathode portion that is included in the X-ray emission module and is based on the nano-structured material.