Bidirectional wavelength division multiplex transceiver module

• US 5,485,538 A
• Filed: 06/30/1994
• Issued: 01/16/1996
• Est. Priority Date: 06/30/1994
• Status: Expired due to Term

• Current Assignee: Kaptron Incorporated, The Whitaker Corporation (Meggitt PLC)
• Original Assignee: The Whitaker Corporation (Meggitt PLC)
• Inventors: Lewis, Warren H., Bergstrom, Richard C., Bowen, Terry P.
• Primary Examiner(s): Ullah, Akm E.
• Application Number:
  US08/269,419
• Time in Patent Office: 565 Days
• Field of Search: 385/10-15, 385/24, 385/27, 385/39, 385/53, 385/60, 385/79, 385/88, 385/92, 385/93, 359/94-95, 359/118-119, 250/203.2, 250/338.1, 356/141.1, 356/4.07, 356/5.01, 372/50
• US Class Current: 385/92
• CPC Class Codes: G02B 6/4246 Bidirectionally operating package structures

Abstract

A compact optical transceiver including a ceramic mounting block 1, with a laser diode 3 abutting a first end of the mounting block for generating light of a first wavelength. A holographic optical element (HOE) 5 is positioned adjacent laser diode 3 and acts as a hologram lens which receives and focuses the generated light to the end face of an optical fiber 13 which is attached to the compact optical transceiver. A glass element 7 is mounted on the mounting block between the diode and the optical fiber end face, and includes dichroic substance 8 coated to the fiber-proximate side of the glass element 7 and acts as a beamsplitter by passing light of a first wavelength and deflecting light of a second wavelength. The glass element 7 is mounted in an angular positioning groove of the mounting block. The beamsplitter 8 receives and passes the generated light of the first wavelength which has been focused by the HOE 5. From a remote transmitter, light of a second wavelength is then transmitted through an optical fiber 13, to the compact optical transceiver from a direction opposite that of the light generated by the laser diode 3. The light transmitted from the optical fiber 13 is then transmitted and output through ferrule 11, attachable to the optical fiber and attached in a second, V-shaped positioning groove of the ceramic mounting block 1. The light of the second wavelength is output to the beamsplitter 8 and is deflected through a bore hole 21 in the ceramic mounting block to a detector 9 abutting the bottom of the mounting block. A blocking filter 15 can be included for blocking light of wavelengths other than the first and second wavelengths from the detector.

Claims

1. A compact optical transceiver comprising:

a mounting block including at least first and second positioning grooves formed therein;

light generating means, abutting a first end of the mounting block, for generating light of a first wavelength emitted in a direction toward an end face of an optical fiber;

light focusing means, mounted adjacent said light generating means so as to receive the generated light, for receiving and focusing the generated light to the end face of the optical fiber;

beamsplitting means, mounted in the first positioning groove of the mounting block, for receiving and passing the generated light of the first wavelength and for receiving and deflecting light of a second wavelength different from the first wavelength;

detecting means, abutting the mounting block, for receiving and detecting the deflected light of the second wavelength; and

a ferrule, attachable to the optical fiber and supported in the second positioning groove of the mounting block, for holding the optical fiber for said end face thereof to receive the focused light of a first wavelength passed through the beamsplitting means and for outputting light of a second wavelength from the optical fiber to the beamsplitting means.

2. The compact optical transceiver of claim 1, wherein the light generating means includes a laser diode.

3. The compact optical transceiver of claim 1, wherein the light generating means is secured between adjustable clamps associated with the mounting block.

4. The compact optical transceiver of claim 3, wherein the clamps are adjustable in at least one of a first direction perpendicular to a direction of travel of the generated light, and a second direction perpendicular to both the first direction and the direction of travel of the generated light.

5. The compact optical transceiver of claim 1, wherein the light generating means generates light of approximately 1.3 μ

m in wavelength.

6. The compact optical transceiver of claim 1, wherein the light focusing means includes a holographic optical element transverse to the direction of the light of the first wavelength.

7. The compact optical transceiver of claim 1, wherein the beamsplitting means includes a dichroic coating formed on a ferrule-proximate side of the glass element.

8. The compact optical transceiver of claim 1, wherein the beamsplitting means passes light of a wavelength less than or equal to approximately 1.3 μ

m and deflects light of a wavelength greater than or equal to approximately 1.55 μ

m.

9. The compact optical transceiver of claim 1, wherein the beamsplitting means includes an antireflective coating on an emitter-proximate side thereof.

10. The compact optical transceiver of claim 1, wherein the detecting means is fixed to the ceramic block within a predetermined tolerance.

11. The compact optical transceiver of claim 1, further including:

a filtering means for blocking light of wavelengths different from the first and second wavelengths.

12. The compact optical transceiver of claim 11, wherein the filtering means includes a blocking filter for blocking received light of a wavelength greater than 1.62 μ

m from being deflected to the detecting means by the beamsplitting means.

13. The compact optical transceiver of claim 11, wherein the mounting block includes a bore hole, through which the deflected light travels from the beamsplitting means to the detecting means, and the blocking filter is mounted in the bore hole interposed between the beamsplitting means and the detecting means.

14. The compact optical transceiver of claim 1, wherein the second positioning groove of the mounting block is a V-shaped groove, in which the ferrule is adjustable in a direction parallel to the direction of travel of the generated light.

15. The compact optical transceiver of claim 1, wherein the mounting block is ceramic.

16. The compact optical transceiver of claim 1, wherein the first positioning groove includes at least one angled side extending in a direction perpendicular to a direction of travel of light from the light generating means.

17. The compact optical transceiver of claim 1, wherein the optical fiber, attached to the ferrule, has an end face with a 6°

-9°

end face angle to prevent transmission of any optical reflection.

18. The compact optical transceiver of claim 1, wherein the second positioning groove is a V-shaped groove, including two angled sides extending in a direction parallel to a direction of travel of the generated light.

19. The compact optical transceiver of claim 1, wherein mounting block, light focusing means, beamsplitting means, detecting means, and ferrule are sealed with a membrane.

20. A compact optical transceiver comprising:

a ceramic mounting block including at least first and second positioning grooves formed therein;

a light source, abutting a first end of the ceramic mounting block, generating light of a first wavelength;

a holographic optical element focusing the generated light into an optical fiber;

a glass element, mounted in the first positioning groove of the ceramic block, the glass element including a dichroic coating on a ferrule-proximate side thereof, receiving and passing the generated light of the first wavelength and receiving and deflecting light of a second wavelength different from the first wavelength, thereby defining a beamsplitter;

a detector, abutting the ceramic block, receiving and detecting the deflected light of the second wavelength; and

a ferrule, attached to the optical fiber and the mounting block, receiving the focused and passed light of a first wavelength and outputting light of a second wavelength from the optical fiber to the dichroic-coated side of the glass element.

21. The compact optical transceiver of claim 20, wherein the light source is secured between adjustable clamps of the ceramic mounting block.

22. The compact optical transceiver of claim 20, wherein the clamps are adjustable in at least one of a first direction perpendicular to a direction of travel of the generated light, and a second direction perpendicular to both the first direction and the direction of travel of the generated light.

23. The compact optical transceiver of claim 20, wherein the holographic optical element is mounted transverse to the direction of the light of the first wavelength.

24. The compact optical transceiver of claim 20, further including:

a filter for blocking light of wavelengths different from the first and second wavelengths.

25. The compact optical transceiver of claim 20, wherein the ceramic mounting block includes a bore hole, through which the deflected light travels from the dichroic mirror side of the glass element to the detector.

26. The compact optical transceiver of claim 20, wherein the second positioning groove of the ceramic mounting block is a V-shaped positioning groove, in which the ferrule is disposed for adjustable movement in a direction parallel to the direction of travel of the generated light.

27. The compact optical transceiver of claim 20, wherein the first positioning groove includes at least one angled side extending in a direction perpendicular to a direction of travel of light from the light generating means.

28. The compact optical transceiver of claim 20, wherein the second positioning groove is a V-shaped groove, including two angled sides extending in a direction parallel to a direction of travel of the generated light.

29. The compact optical transceiver of claim 20, wherein the beamsplitter passes light of a wavelength less than or equal to approximately 1.3 μ

m and deflects light of a wavelength greater than or equal to approximately 1.55 μ

m.

30. The compact optical transceiver of claim 20, wherein the beamsplitter includes an antireflective coating on an emitter-proximate side thereof.