Fiber optic transceiver

• US 6,865,346 B1
• Filed: 06/05/2001
• Issued: 03/08/2005
• Est. Priority Date: 06/05/2001
• Status: Active Grant

• Current Assignee: Silicon Light Machines Corporation (SCREEN Holdings Co., Ltd.)
• Original Assignee: Silicon Light Machines Corporation (SCREEN Holdings Co., Ltd.)
• Inventors: Miller, Gregory, Berger, Josef
• Primary Examiner(s): Chan, Jason
• Assistant Examiner(s): TRAN, DZUNG D
• Application Number:
  US09/875,499
• Time in Patent Office: 1,372 Days
• Field of Search: 398/135, 398/136, 398/139, 398/169, 398/170, 398/183, 398/201
• US Class Current: 398/135
• CPC Class Codes: H04B 10/2587 using a single light source for multiple stations

Abstract

A fiber optic transceiver capable of bi-directional communication comprises an incoming optical (downlink) signal, a detector comprising a detecting surface configured to detect a detected portion of the incoming optical signal that strikes the detecting surface, and a light modulator for modulating a reflected (uplink) signal. The reflected signal comprises a reflected portion of the incoming signal. The light modulator comprises a controllable reflection member for modulating the reflected signal, and a controller configured to control the controllable reflection member. The controllable reflection member implements micro-electro-mechanical systems (MEMS) technology wherein micro-reflective surfaces are physically positioned or oriented by the control signal, thereby affecting reflection and diffraction in such a way as to modulate the intensity of light entering an uplink channel.

Claims

1. A fiber optic transceiver capable of bi-directional communication comprising:

a. an incoming optical signal;

b. a detector comprising a detecting surface configured to detect a detected portion of the incoming optical signal that strikes the detecting surface;

c. a light modulator for modulating a reflected signal; and

d. a focusing member; and

e. an optical channel,

wherein the reflected signal comprises a reflected portion of the incoming signal,

wherein the light modulator comprises a controllable reflection member for modulating the reflected signal,

wherein the controllable reflection member is mounted on a tilting plate operatively coupled with a stable surface,

wherein an angle of the tilting plate relative to the incoming optical signal is controlled,

wherein the tilting plate is controllably positionable at a first angle and a second angle,

wherein the tilting plate, the focusing member and the optical channel are configured such that a positioning of the tilting plate at the first angle directs the reflected signal through the focusing member in a manner calculated to impart a first intensity of the reflected signal into the optical channel, and a positioning of the tilting plate at the second angle directs the reflected signal through the focusing member in a manner calculated to impart a second intensity of the reflected signal into the optical channel, and

wherein the first and second intensity levels are distinct.

2. The fiber optic transceiver according to claim 1 wherein a path followed by the reflected signal from the controllable reflection member to the focusing member is a straight line.

3. The fiber optic transceiver according to claim 1 wherein the tilting plate is controllably positionable at a third angle, wherein an intensity level of the reflected signal entering the optical channel when the tilting plate is at the third angle comprising a third intensity level.

4. The fiber optic transceiver according to claim 1 wherein the detecting surface comprises an integrated photodiode.

5. The fiber optic transceiver according to claim 1 wherein the reflected signal is modulated by the modulator at a frequency substantially slower than a frequency of the incoming optical signal.

6. The fiber optic transceiver according to claim 1 wherein the detecting surface is also mounted on the tilting plate.

7. The fiber optic transceiver according to claim 1 wherein the angle of the tilt plate is controlled through a controllable electric field.

8. The fiber optic transceiver according to claim 7 wherein the controllable electric field is disposed within the stable surface.

9. A fiber optic transceiver capable of bi-directional communication comprising:

a. an incoming optical signal;

b. a detector comprising a detecting surface configured to detect a detected portion of the incoming optical signal that strikes the detecting surface;

c. a light modulator for modulating a reflected signal,

wherein the reflected signal comprises a reflected portion of the incoming signal,

wherein the light modulator comprises a controllable reflection member for modulating the reflected signal,

wherein the detecting surface comprises an integrated photodiode, and

wherein the reflection member comprises a diffraction grating comprising a plurality of elongated elements, including a first elongated element with a first reflective surface defining a first plane and a second elongated element defining a second plane substantially parallel to the first plane, and

wherein a separation distance between the first plane and the second plane is controllable to a first separation distance and a second separation distance, the first separation distance calculated to create a first pattern of light distribution within the reflected signal, and the second separation distance calculated to create a second pattern of light distribution within the reflected signal.

10. The fiber optic transceiver according to claim 9 further comprising an optical channel, wherein the first pattern of light distribution is configured to provide a first intensity of the reflected signal into the optical channel, and the second pattern of light distribution is configured to provide a second intensity of the reflected signal into the optical channel, wherein the first and second intensities are distinct.

11. The fiber optic transceiver according to claim 10 wherein the first and second intensities of the reflected signal are directed into the optical channel by a focusing member.

12. The fiber optic transceiver according to claim 11 wherein a path followed by the reflected signal from the controllable reflection member to the focusing member is a straight line.

13. The fiber optic transceiver according to claim 10 wherein the first pattern of light distribution pattern exhibits no substantial diffraction.

14. The fiber optic transceiver according to claim 13 wherein the second pattern of light distribution is a diffraction pattern.

15. The fiber optic transceiver according to claim 14 wherein the separation distance is further controllable to a third separation distance resulting in a third light distribution pattern within the reflected signal, the third light distribution pattern selected to provide a third intensity of the reflected signal into the optical channel.

16. The fiber optic transceiver according to claim 9 wherein the separation distance between the first plane and the second plane is controlled through a controllable electric field configured to deflect select elongated elements.

17. The fiber optic transceiver according to claim 16 wherein the controllable electric field is disposed within a substrate.

18. The fiber optic transceiver according to claim 16 wherein the detecting surface is disposed between the incoming signal and the substrate.

19. The fiber optic transceiver according to claim 16 wherein the substrate is disposed between the incoming signal and the detecting surface, and wherein the substrate is selected from a material which will allow a portion of the incoming signal to pass through the substrate.

20. The fiber optic transceiver according to claim 9 wherein the detecting surface comprises an integrated photodiode.

21. The fiber optic transceiver according to claim 9 wherein the reflected signal is modulated by the modulator at a frequency substantially slower than a frequency of the incoming optical signal.

22. A method for transmitting an optical signal comprising the steps:

a. receiving an incoming optical signal;

b. reflecting a portion of the incoming signal off of a reflective member, thereby forming a reflected signal; and

c. controlling the reflecting member to modulate the signal containing information,

wherein the reflecting member comprises a first elongated member with a first planar surface defining a first plane and a second elongated member with a second planar surface defining a second plane, the first and second planar surfaces being substantially parallel, and wherein the step of controlling the reflecting member further comprises the steps;

a. controlling a separation distance between the first plane and the second plane; and

b. directing the reflected signal through a lens,

wherein the step of controlling the separation distance between the first plane and the second plane is calculated to control a diffraction pattern in such a way as to control an intensity of reflected light entering an optical channel.

23. The method of claim 22 wherein the reflected signal travels a straight line from the reflecting member to the lens.