Electro-optic modulator

• US 9,170,439 B2
• Filed: 09/12/2012
• Issued: 10/27/2015
• Est. Priority Date: 09/05/2012
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Gill, Douglas M., Green, William M., Valdes Garcia, Alberto
• Primary Examiner(s): Stahl, Mike
• Application Number:
  US13/611,238
• Publication Number:
  US 20140061450A1
• Time in Patent Office: 1,140 Days
• Field of Search: None
• US Class Current: 1/1
• CPC Class Codes: G02F 1/0121 Operation of devices; Circuit arrangements, not otherwise provided for in this subclass
• CPC Class Codes: G02F 1/0356 controlled by a high-frequency electromagnetic wave component in an electric waveguide structure

Abstract

A method for controlling an electro-optic modulator device includes measuring a performance metric of the device to define a first measured performance value, and changing a state of a first tuning portion of the device to connect the first tuning portion to ground.

Claims

1. A method for controlling an electro-optic modulator device, the method comprising:

measuring a performance metric of the device to define a first measured performance value and a second measured performance value; and

selectively changing a state of a plurality of tuning portions of the device, the plurality of tuning portions of the device including a first tuning portion of the device having a first switch portion to connect the first tuning portion to ground, and a second tuning portion of the device having a second switch portion to connect the second tuning portion to ground,

wherein each tuning portion is arranged proximate to a conductive line portion that partially defines a radio frequency (RF) signal path, and changing the states of the first and second tuning portions adjusts an effective capacitance of the conductive line to affect a velocity of the RF signal.

2. The method of claim 1, further comprising:

measuring the performance metric of the device to define the second measured performance value responsive to changing the state of a first tuning portion of the device to connect the first tuning portion to ground; and

determining whether the second measured performance value is greater than the first measured performance value.

3. The method of claim 2, further comprising:

determining whether the second measured performance value is less than the first measured performance value responsive to determining that the second measured performance value is not greater than the first measured performance value; and

changing a state of the first tuning portion of the device to disconnect the first tuning portion from ground responsive to determining that the second measured performance value is less than the first measured performance value.

4. The method of claim 3, wherein the method further comprises changing a state of a second tuning portion of the device to connect the second tuning portion to ground responsive to determining that the second measured performance value is greater than the first measured performance value.

5. The method of claim 4, further comprising measuring the performance metric of the device to define a third measured performance value responsive to changing the state of a second tuning portion of the device to connect the second tuning portion to ground;

and

determining whether the third measured performance value is greater than the second measured performance value.

6. The method of claim 5, further comprising:

determining whether the third measured performance value is less than the second measured performance value responsive to determining that the third measured performance value is not greater than the second measured performance value; and

changing a state of the second tuning portion of the device to disconnect the second tuning portion from ground responsive to determining that the third measured performance value is less than the second measured performance value.

7. A method for controlling an electro-optic modulator device, the method comprising:

measuring a performance metric of the device to define a first measured performance value; and

changing a state of a first tuning portion of the device to connect the first tuning portion to ground, wherein the first tuning portion includes a conductive portion disposed in an arrangement overlapping a conductive line portion of the electro-optic modulator device, and the connecting first tuning portion to ground is operative to increase the capacitance of the conductive portion.

8. The method of claim 7, further comprising:

measuring the performance metric of the device to define a second measured performance value responsive to changing the state of a first tuning portion of the device to connect the first tuning portion to ground; and

determining whether the second measured performance value is greater than the first measured performance value.

9. The method of claim 8, further comprising:

determining whether the second measured performance value is less than the first measured performance value responsive to determining that the second measured performance value is not greater than the first measured performance value; and

changing a state of the first tuning portion of the device to disconnect the first tuning portion from ground responsive to determining that the second measured performance value is less than the first measured performance value.

10. The method of claim 9, wherein the method further comprises changing a state of a second tuning portion of the device to connect the second tuning portion to ground responsive to determining that the second measured performance value is greater than the first measured performance value.

11. The method of claim 10, further comprising measuring the performance metric of the device to define a third measured performance value responsive to changing the state of a second tuning portion of the device to connect the second tuning portion to ground;

and

determining whether the third measured performance value is greater than the second measured performance value.

12. The method of claim 11, further comprising:

determining whether the third measured performance value is less than the second measured performance value responsive to determining that the third measured performance value is not greater than the second measured performance value; and

changing a state of the second tuning portion of the device to disconnect the second tuning portion from ground responsive to determining that the third measured performance value is less than the second measured performance value.

13. A method for controlling an electro-optic modulator device, the method comprising:

selectively changing a capacitance of a conductive line portion of the electro-optic modulator device based on at least one measured performance value of the electro-optic modulator device, the conductive line portion operative to propagate a radio frequency (RF) signal that is operative to interact with, and modulate an optical signal,

wherein the changing the capacitance of the conductive line portion comprises selectively changing a state of at least one tuning portion among a plurality of tuning portions of the electro-optic modulator device to adjust the capacitance of the conductive line portion and affect a velocity of the RF signal.

14. The method of claim 13, wherein the optical signal is propagated in a waveguide portion of the electro-optic modulator device arranged proximate to a portion of the conductive line portion.

15. The method of claim 14, wherein the changing the capacitance of the conductive line portion includes increasing the capacitance of the conductive line portion to affect the velocity of the RF signal.

16. The method of claim 15, wherein the increasing the capacitance of the conductive line portion is operative to reduce a difference between the velocity of the RF signal and the velocity of the optical signal.

17. The method of claim 13, wherein the changing the capacitance of the conductive line portion comprises decreasing the capacitance of the conductive line portion.

18. The method of claim 17, wherein the decreasing the capacitance of the conductive line portion affects the velocity of the RF signal.

19. The method of claim 18, wherein the decreasing the capacitance of the conductive line portion is operative to reduce a difference between the velocity of the RF signal and the velocity of the optical signal.